CA2331500A1 - Implantable medical device for tracking patient functional status - Google Patents

Implantable medical device for tracking patient functional status Download PDF

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Publication number
CA2331500A1
CA2331500A1 CA002331500A CA2331500A CA2331500A1 CA 2331500 A1 CA2331500 A1 CA 2331500A1 CA 002331500 A CA002331500 A CA 002331500A CA 2331500 A CA2331500 A CA 2331500A CA 2331500 A1 CA2331500 A1 CA 2331500A1
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display
activity
values
value
patient
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French (fr)
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Karen A. Stone
Rama V. Padmanabhan
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Medtronic Inc
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/0002Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network
    • A61B5/0031Implanted circuitry
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/103Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
    • A61B5/11Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb
    • A61B5/1118Determining activity level
    • GPHYSICS
    • G16INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16HHEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA
    • G16H40/00ICT specially adapted for the management or administration of healthcare resources or facilities; ICT specially adapted for the management or operation of medical equipment or devices
    • G16H40/60ICT specially adapted for the management or administration of healthcare resources or facilities; ICT specially adapted for the management or operation of medical equipment or devices for the operation of medical equipment or devices
    • G16H40/63ICT specially adapted for the management or administration of healthcare resources or facilities; ICT specially adapted for the management or operation of medical equipment or devices for the operation of medical equipment or devices for local operation
    • GPHYSICS
    • G16INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16HHEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA
    • G16H40/00ICT specially adapted for the management or administration of healthcare resources or facilities; ICT specially adapted for the management or operation of medical equipment or devices
    • G16H40/60ICT specially adapted for the management or administration of healthcare resources or facilities; ICT specially adapted for the management or operation of medical equipment or devices for the operation of medical equipment or devices
    • G16H40/67ICT specially adapted for the management or administration of healthcare resources or facilities; ICT specially adapted for the management or operation of medical equipment or devices for the operation of medical equipment or devices for remote operation
    • GPHYSICS
    • G16INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16HHEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA
    • G16H50/00ICT specially adapted for medical diagnosis, medical simulation or medical data mining; ICT specially adapted for detecting, monitoring or modelling epidemics or pandemics
    • G16H50/30ICT specially adapted for medical diagnosis, medical simulation or medical data mining; ICT specially adapted for detecting, monitoring or modelling epidemics or pandemics for calculating health indices; for individual health risk assessment
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/72Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7232Signal processing specially adapted for physiological signals or for diagnostic purposes involving compression of the physiological signal, e.g. to extend the signal recording period

Abstract

An implantable medical device (71a, 71g, 71c) determines activity levels ove r a set of time periods, preferably on the order of seconds, minutes and hours and a display (82) is enabled for days or weeks at recorded activity levels over a range of dates. This enables physician review of patient functional status. Additional physiologic data can be recorded along with the activity data, and this too may be reported out from the implanted device to a medica l communications system for alarm purposes, titrating drugs or other monitorin g tasks.

Description

IMPLANTABLE MEDICAL DEVICE FOR TRACKING PATIENT FUNCTIONAL STATUS
Background.
There are numerous devices both implantable and external that have been used to monitor various medical patient conditions. Well known for heart patients is the Holter monitor which permits somewhat uncomfortable monitoring of an electrocardiogram for 24 hours which can then be read by a physician to find 1o anamolies in the rhythm which were not susceptible to discovery or confirmation in a patient's office visit to the doctor. A number of other devices have improved on the ability to maintain records of electrocardiograms and numerous other health related patient parameters and even device performance parameters. Implantable medical devices such as pacemakers and cardioverter-defibrillators and even non-~5 therapeutic monitoring devices are currently capable of maintaining some records and reporting out such data. An example of a non-therapy delivering monitoring implantable medical device can be seen in US Patent Nos. 5,313,953 and 5,411,031 issued to Yomtov et al., and in Holsbach et al, 5,312,446, and others. Nolan et al,'s US Pat. No. 5,404,877 teaches that such devices can even generate patient 2o alarms. All these patents are incorporated herein by this reference in that they provide information about what can currently be done in the implantable device field.
Current generation pacemakers and implantabie defibrillators/cardioverters have the 25 ability to store different types of information in order to provide feedback to the clinician about the patient/device system. Examples of stored information include arrhythmia diagnostics, histograms of paced and sensed events, electrograms and trends of lead impedance. Such information is useful not only in optimizing device programming but also in the management of the patient's arrhythmias and other 3o conditions. While our invention focuses on the monitoring of patient activity, WO 99/58056 pCT/US99/10282 which we use as a functional status monitor, the additional information available from implantable devices could be used as an adjunct.
However, to date the literature is devoid of a satisfactory description of how to use activity information. There has been considerable thinking in this area, but none have yet succeeded in producing a satisfactory measure to track patient functional status. Some examples of this thinking in the current literature include:
Walsh J. T., Charlesworth A., Andrews R., Hawkins M., and Cowley A. J. "
1o Relation of daily activity levels in patients with chronic heart failure to long-term prognosis", Am J Cardiol, 1997, 79: 1364-1369.
Rankin S. L. , Brifa T. G. , Morton A. R. , and Hung J. , "A specific activity questionnaire to measure the functional capacity of cardiac patients", Am J
Cardiol 1996, 77: 1220-1223.
~s Davies S. W., Jordan S. L., and Lipkin D. P., "Use of limb movement sensors as indicators of the level of everyday physical activity in chronic congestive heart failure", Am J Cardiol 1992, 67: 1581-1586.
Hoodless D. J. , Stainer K. , Savic N. , Batin P. , Hawkins M. and Cowley A.
J. , "
2o Reduced customary activity in chronic heart failure: assessment with a new shoe-mounted pedometer", International Journal of Cardiology, 1994, 43: 39-42.
Alt E. , Matula M. , Theres H. , Heinz M. and Baker R. , " The basis for activity controlled rate variable cardiac pacemakers: An analysis of mechanical forces on 2s the human body induced by exercise and environment", PACE, vol 12, Oct, 1989.
Lau C. P., Mehta D., Toff W. D., Stott R. J., Ward D. E. and Camm A. J., "
Limitations of rate response of an activity sensing rate responsive pacemaker to 3o different forms of activity ", PACE, vol. 11, Feb 1988, and Lau C. P. , Stott J. R. R. , Zetlin M. B. , Ward A. J. , and Camm A. J. , "
Selective vibration sensing: a new concept for activity-sensing rate-responsive pacing", PACE, vol. 11, September, 1988. Matula M. , Schlegl M. , and Alt E. , "
Activity controlled cardiac pacemakers during stairwalking: A comparison of s accelerometer with vibration guided devices and with sinus rate", PACE, 1996, vol 19, 1036:1041.
Suecific information uses:
The ability to perform normal daily activities is an important indicator of a patient's to functional status and is related to improved quality of life in patients.
An increase in the ability to perform activities of daily living (ADL) is an indicator of improving health and functional status, while a decrease in the ability to perform daily activities may be an important indicator of worsening health. Activities of daily living are submaximal activities performed during daily life. Examples are going to 1s work, cleaning the house, vacuuming the house, cooking and cleaning, working in the garden, short walk to grocery stores, cleaning the car, and slow paced evening walks.
In order the assess the amount of daily activities that patients can perform and the 2o ease with which they can perform these activities, clinicians typically ask their patients during office visits the following questions:
~ How do you feel ?
~ Are you as active today as you were 2 months ago ?
~ Are you as active today as you were 6 months ago ?
2s ~ Are you able to climb stairs ?
~ How far can you walk ?
~ Do you do your own grocery shopping?
~ Do you perform chores around the house ?
~ Are you able to complete your activities without resting ?
They also employ other tools such as the symptom based treadmill exercise test, the 6 minute walk test, questions and answers (Q&A) , and quality of life(QOL) questionnaires in order to learn about their patients' ability to perform exercise and normal activities, but these assessment tools have limitations. Q&A techniques are subjective and biased towards recent events(at least partly due to patient bias toward present recall, if not also due to patient memory impairment or insufficiency, or a patient's desire to provide positive data). Maximal treadmill exercise tests assesses the patient's ability to perform intense (maximal) exercises and do not reflect the 1o ability to perform normal daily activities. The 6 minute walk test has to be administered very carefully and rigorously to achieve valid results.
Impairment of functional status can be seen in changes in the ability to perform exercises and ADL. This can be affected by many physiological factors such as ~s progressive decompensation in the setting of left ventricular cardiac (LV) dysfunction, beta blocker treatment, symptomatic arrhythmias, and depression.
These changes may take place over a long period of time and may be too subtle to be discerned by patients.
2o Physicians use answers to these questions and observation in clinic to determine what New York Heart Association "class" into which a patient falls, and on this basis, among others, they administer and alter treatment. Class I is defined as "Patients with cardiac disease but without resulting limitation of physical activity.
Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea or 25 anginal pain. " NYHA Class II is "Patients with cardiac disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea or anginal pain. ", Class III is defined: "Patients with marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes fatigue, palpitation, dyspnea, 30 or anginal pain. And, Class IV is "Patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms of heart failure or of the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort is increased. "
As implantable device technology advances, there is a further need to provide 5 information that will allow the clinician to not only manage arrhythmias better but also the progression of other diseases (co-morbidities) that patients may have. With the advent of newer drugs and newer paradigms in drug therapy (the use of beta blockers in heart failure patients is just one example), there is a need for objective measures of patient response. Several parameters such as ventricular pressure, patient activity, lung wetness, and heart rate variability may provide such information to the clinician.
In the management of patient care over a relatively long period of time, it is believed that current implantable devices with their larger memories and even using ~s some extant sensors may be enhanced to produce a set of data that indicates patient functional status on an on-going basis. For patients who do not have already a need for an implanted medical device as an adjunct to their medical therapy, the addition of a specialized implantable that has extremely limited capability and thus small size may provide an additional tool for medical management of disease, particularly 2o Cardiac Heart Failure (CHF).
However, it seems that the simplest and possibly most accurate measurement which can determine the prognosis and progress of a patient has not been previously monitored, and further this indicator has not been monitored in a manner effective 2s to elucidate for the physician the changing character of the patient's CHF
disease progression.
If there were a simple and yet effective measure that could be reliably correlated with the progress of CHF, the use of other hemodynamic measures could be used to 3o supplement it and could easily be added to an implantable device. This indication alone may provide a sufficient justification for implantation of a device. In other words, if a very inexpensive implantable device could be developed to chronically monitor a simple indicator of CHF prognosis, the care available to CHF
patients could be improved by using this data. Administration of patient care based on this inexpensive implant's data would improve the lives of CHF patients by virtue of their needing less frequent clinic visits for drug titration and other observationally intense activities, since the status of the patient could be determined without resort to an expensive doctor visit by merely and viewing the data from these CHF
status indicators, the drugs themselves could be adjusted, alarms could be sent, and other therapies automatically adjusted based on this status report. It is believed that the ~o common usage of such systems awaits the development of an information resource such as is taught in this patent.
We have determined that a long term trend of physical activity in CHF patients may thus provide the clinician with an objective measure of the patient's life-style and 1s functional status, and can be used in conjunction with other information, but as explained previously, an objective long term measure is currently unavailable from implantable medical devices. Having available a display of a trend of patient ability to perform ADL is useful in several situations.
2o Correlation of physical activity with patient testimony.
Clinicians often encounter patients who find it difficult to verbalize their symptoms clearly. In such situations, an objective measure of patient activity stored in the device may help the clinician to decide an appropriate course of action. For 25 example, if a patient complains vaguely of fatigue and shortness of breath and is not able to describe the limitations to his/her daily activities, a trend of activities may help the clinician. If the activity data could show a considerable decrease in patient activities, then the clinician may take the next step such as the evaluation of cardiac profile, pulmonary dysfunction, or existing drug therapy. On the other hand, if the 30 long term trend of activity in this patient is consistently regular, (i.e., no decrease in patient activity), the clinician may take alternative steps to understand the difference between patient symptoms and device indicated activity data.
Clinicians may also encounter situations when patients are reluctant to discuss their s symptoms. In situations such as these, a trend of activity data may help the clinician to question the patient or the patient's spouse and enable the patient to come forward with their symptoms Correlation of physical activity with onset or progression of Heart Failure.
io Heart Failure is a syndrome characterized by the coexistence of left ventricular dysfunction (low EF), arrhythmias, pulmonary and peripheral congestion, and symptoms of fatigue and shortness breath. A majority of ICD patients have low EF
( < 40~) and decreased functional capacity (NYHA Class II, III and IV), and are at risk of developing heart failure. Clinical heart failure is a progressive disease;
is hence early identification and timely therapy may prevent hospitalizations, reduce the cost of care and improve patient lives.
In the earlier stages of heart failure, patients may not be able to perform strenuous activities and in the later stages, may not be able to perform even routine activities 2o such as walking up a flight of stairs. Further, the inability to perform exercise and activities develop over a long period of time and hence may be difficult to discern and quantify. An objective measure of long term trends of patient activity may be useful in early identification of symptoms of heart failure and in the progression of heart failure. A gradual decrease in patient activities over the last 8 months may 2s lead the clinician to suspect the development of heart failure. This may lead the clinician to take the next step in differential diagnosis.
The ability to perform daily activities is of particular relevance to the onset and progression of heart failure. Several studies in the literature have described the need 3o for an objective measurement of activities of daily living in patients with heart failure. This is no doubt why the NYHA measures focus so much on this ability to perform daily activities.
Correlation of physical activity with patient response to therapy.
s The use of beta-blockers in patients at risk of arrhythmias or heart failure is becoming common clinical practice. Beta-blocking agents are known to blunt the heart rate response, which may affect the patient's ability to perform certain activities. The optimal dosage of beta-blocking agents is difficult to predict and may require trial and error methods. Further, there is usually a 30-60 day time period 1o immediately after initiation of drug therapy during which the patient may not be very active. Most patients acclimate to the therapy after this period, but some don't.
By having an objective measurement of patient activities, the titration and adjustment to beta blockers and other drugs could be enhanced.
Correlation of physical activity with arrhythmias.
~s Arrhythmias may cause symptoms such as palpitations, fatigue, or presyncope.
Some patients may spend a significant amount of time in arrhythmias such as atrial fibrillation and may not be able to perform daily activities. Such issues can be coordinated with measurements of activity for increased diagnostic value.
As is known in the art, implantable medical devices exist that have various accelerometers and piezocrystal activity sensors and the like which count the movement of the crystal or sensor with respect to a resting state. Medtronic brand implantable medical devices with piezoelectric crystal or accelerometer based activity sensors have the ability to convert a raw activity signal into the 2 second activity counts. In other words, the number of times the accelerometer or sensor moves in a two second period is called a 2 second activity count. However, nothing in the art describes a method or apparatus for succinctly and effectively compiling such data as activity counts to make that data effective to solve the problems in diagnosis and patient tracking described above.
What is needed is a device with a system to convert these activity counts or some equivalent of them into a measure of patient activity that is clinically meaningful.
To review the specifics of the problem consider the raw signal. The raw activity signal and hence the processed activity counts is a result of vibrations due to body movement. Activities such as walking and running cause body movement and 1o vibration; the faster or longer the walk, more the vibrations, and larger the activity signal. Even though the raw activity signal is a good measure of activities such as walking and running, these raw counts, without our invention do not provide an accurate assessment of patient physical exertion. This is for three classes of reasons.
1. Body vibrations are not always proportional to level of exertion.
Any activity that causes body movement such as walking and running will generate an activity signal. Studies have shown that the amplitude of the activity 2o counts increases in a linear fashion for walking activities. However, this linear relationship between intensity of activity and the activity signal during walking does not apply to all activities. For example, walking up-stairs at the same speed will produce activity counts similar to walking on a flat surface even though the intensity of activity is higher while walking upstairs. Other examples are isometric exercise, stationary bike, and jogging in place. Since the activity counts are derived from this activity signal, they may not be an objective measure of patients' exertion levels for all types of activity. In fact even a simple activity such as walking may produce different activity counts depending on the human-ground interface, for example, walking on a carpeted surface versus an asphalt surface.
2. Lack of specificity.

Activities such as automobile driving that result in body vibrations but do not involve exertion may sometimes produce an activity signal that may be comparable in amplitude to the level of the activity signal during walking. Likewise, the s orientation of an accelerometer may not pick up an activity like push ups, despite the large exertion.
3. Inter-person variability.
1o There is also inter-person variability for similar activities. Differing size and fat content of the patient body, as well as placement of the device in various locations and orientations will all contribute to this kind of variability.
Based on these considerations, it is clear that in order to convert the activity counts to a meaningful measure of patient activity, the system must 1. be sensitive enough to pick up low-level activities (activities of daily living) as well as high-level exertion activities, 2. minimize response to activities such as automobile driving, 3. be patient independent, i.e., it should not require a user programmable parameter and should 4. be easy to implement in an implantable device Brief Description of the Drawings.
Figs. 1-3 are graphs of time versus activity counts over time in accord with preferred embodiments of the invention, used to describe various changes in patient 3o condition over time.

Figs. 4a-c are similar graphs of activity versus time.
Figs. Sa and Sb are graphs of atrial fibrillation versus time and activity versus time using the same time axis.
Fig. 6 is a graph indicating a NYHA class level with patient activity over time.
Fig. 7 is a drawing of the inside of a patient's body having three implants within it on the right side of a line BL and an external programmer for communication with 1o the implantable devices.
Summary of the invention.
This invention provides a patient activity monitor for chronic implant which is provides well correlated evidence of the functional status of the patient with the implant. It does so by monitoring an activity signal related to the movement of the patient, and from this monitored movement determining a level of activity indication signal value.
2o Detailed description of the preferred embodiments Nearly any currently implanted medical devices could be adapted to employ the features of this invention provided only that such a device maintains either a direct and constant link with a memory device or has its own memory device and its own activity sensor, and that there is provided an appropriate processing circuit or 25 program to enable the invention activity. Activity sensors are well known and have been employed in pacemaker type implantable medical devices for many years. A
typical such device is seen in Strandberg's US patent No. 4,886,064, and it is now common to see the basic activity sensor combined with alternative means for sensing activity such as minute ventilation as in US Patent No. 5,562,711, both of 3o which are hereby incorporated by this reference in their entireties.

Referring now to Fig. 7, in which a set of alternative implantable devices 71a-c are illustrated inside of a patient body, (the edge of which is here illustrated as line BL,) the typical application of this invention will be to provide data for a display 82 on an external device such as a programmer P external to the patient body, via a conununications channel such as is here represented by double headed arrow C.
The data may be shown in the form of a bar chart or line graph or similar display which indicates the total amount of some algorithmically derived measure of activity over a given period of time, such as a.day or an hour. Device 71a is a pacemaker having a memory 75a which stores the data measured by the sensor 76a. The storage can be in a raw form if there is sufficient memory or it can be compressed in various advantageous forms by a program or other circuit device running a process such as processor 77a. In this embodiment, the microprocessor 77a runs a program stored in memory to convert sensed activity counts processed through an analog to digital converter 79 as they appear on a bus 78, and then returns the 1s processed data to the program for temporary storage in the memory circuit 75a.
When enough measurements are made in accord with the program, the microprocessor converts a representation of the total to a value and stores the representation in the memory. When an external device such as a programmer P
requests a dump of these stored representations of value indicating the amount of 2o patient activity over time, it is formatted and sent over the communications channel by a communications circuit 83 to the external device so that it can be displayed in a human readable form. Alternatively, of course, the data can be sent via communications here simply represented by arrow C2 and arrow L1 to be stored in a temporary device TD for later relaying to other devices by phone or othe 25 rtelemetry, here represented simply by line L2, for later or contemporaneous but distant display. Only the simplest construction required for operative use of the invention is shown here. It is a simple matter to resend data over modern communications systems once it is retrieved in a machine readable format. As most implantable cardioverter defibrillators and pacemakers of today have 3o microprocessors, memories and activity sensors, the addition of this invention to such devices would require no additional hardware, but mere software reconfiguration to accommodate the requirements of storing appropriate activity data in a useful manner so as a to be available for use in accord with this invention.
Also, alternative forms of implant devices can be used. The Medtronic device REVEAL(TM), for example is fully implantable and similar to the device illustrated as device 71 c, with a memory and processing circuitry for storing electrocardiograms, taken across two electrodes 79 and 72c. The addition of an additional circuit for sensing activity and appropriate circuitry to implement the storage of the relevant activity data in an appropriate manner would make this type of device another good candidate for the inventive features herein described.
Also a drug pump such as device 71b when outfitted with the appropriate memory, processing and sensing circuits could do the same, as could other currently implantable devices. It should be noted that a device with nothing but an activity sensor, memory, a processor and some form of communications circuit would also be sufficient to perform the tasks required of this invention's implantable device.
By using a kinetic power source, the dependence on a battery could be eliminated too and the device could be extremely small and unobtrusive, permitting the clinician to easily obtain patient consent to accept the implant.
2o Once the valuable functional status data is available, any communications system could be employed to get the information to the doctor, or to update the patient file.
Any such uses of the information provided by this invention are contemplated.
Fig. 1 is a prototype illustration (using simulated data) over a 14 month period of 2s patient activity data. Note that the patient can be seen over a very long period and any changes in the activity amount will be readily visible. Also, as illustrated here, even fairly large variations in daily activity will not influence the overall impression of health. Here the graph 10 displays hours in which the activity count was in the active range per day 12 versus time 13 on the line 11. In Fig. 2, the activity line 15 3o begins trending downward in late September confirming that the patient should be seen at the time shown 16.

Figure 3 illustrates a long term trend of patient activity data. This situation may be that of a post myocardial infarction (MI), sudden cardiac death survivor with EF <
40 % .
In the Figs. 4a-c are prototypical illustrated activity trends for patients with a drug therapy intervention. In case 1, Fig 4a, graph 20a, line 21a shown little or no effect of the drug regimen. the patient report at the time he is seen will probably indicate no change in status, based on the height of curve 21a. In case 20b, the to drug administration has an apparent effect by the time the patient is seen, which in graph 20c, the line 21c shown no effect of the Beta blocker administration.
Thus, objective measurement of patient activities as illustrated in Figures 4a-c can provide feedback to the clinician during the use of beta blocker therapy. Figure 4a is a scenario where activities are not decreased. Fig. 4b illustrates a temporary decrease ~5 in patient activities followed by an increase to the original level. Fig.
4c shows that patient activities decreased and stay decreased, and may require the modification to the drug dosage.
Figs 5 a and Sb show how the activity data can be coordinated with a display of 20 other patient related data, here hours in atrial fibrillation per day. Note the apparent correlation with the height of the line 21d and the increased occurrence of Atrial Fibrillation as would be expected. A device such as 71c which could track both fibrillation's and activity could be used to produce such a paired graph display. The ability to correlate the duration of arrhythmia episodes with patient activity as 2s shown in Figure 5 may help the physician in treating the arrhythmias. For example, if the patient is being monitored with a device that can display the occurrence of an arrhythmia or an accumulation of arrhythmic events over time as shown in this figure, or if such a feature is incorporated into the inventive device, the physician can learn immediately whether the arrhythmia occurs with activity, an 3o important piece of diagnostic information.

Figure 6 illustrates correspondence with physician determined NYHA Class level of a CHF patient over a relatively short time period with his activity level in hours along the vertical axis. This chart shows the NYHA Classification and activities per day for the 7 follow-ups. As can be seen in the figure, activities per day appear to 5 be increasing over time in correlation with the improvement in NYHA
functional Classification from Class III to Class I/II.
In order to explain how the compilation of useful information from the raw data can be accomplished, refer first to Fig. 8 in which activity counts from a normal subject collected over a 24 hour period is shown.
These signals can be collected from pacemakers which have been using piezoelectric crystals and accelerometers mounted inside the pacemaker can as an indicator of patient activity to control the rate of the pacemaker. Typically, the raw 1s acceierometer/crystal signal is first filtered using a bandpass filter and the total number of crossings above and below a fixed threshold is calculated every 2 seconds. The rate of the pacemaker is then calculated based on these 2 second activity counts. These 2 second activity counts can also be used to acquire information regarding patient activity. For heart rate and Heart Rate 2o Variability(HRV), most pacemaker devices already have the ability to calculate heartbeat intervals and changes in these calculated variables over time gives the HRV. Other measures such as breathing rate, oxygen saturation, blood pressure, temperature, or just about any other measurement that can be made could be coordinated with the activity display to provide useful information, but we only show HRV here to teach that such can be easily done, not to limit the invention to this one coordination display.
These observations are evidence that the concept of using the accelerometer signal to differentiate between activities and non-activities is appropriate and acceptable.

Description of candidate algorithms for implementing this- invention~
Based on the concerns just described we selected 5 candidate algorithms for determining a value for activity level per day, and we tested these on a large set of 24 hour data. A description of the 5 algorithms follow. These are examples only.
We ultimately selected as a most preferred algorithm one which uses 60second periods rather than 80, to provide easier conversion to minutes and hours. We also found that in producing a display it was sensible to average the daily values for a week, since normal activity cycles over a week can vary significantly over a weekend, particularly.
ADLl: First, the average activity count over 80seconds is calculated by adding consecutive 2 second counts. The average is then compared with a threshold of 1.5.
If the average is greater than or equal to 1.5, then the 80s period is considered as activity (ADL), and the average for the next 80s time period is calculated. At the end of the 24 hour data, total activity duration is calculated by adding the number of 80 second windows that were detected as ADL, and multiplying with 80.
ADL2: This algorithm is similar to ADL1 except for the choice of threshold (2.0).
This choice was made to evaluate the trade-off between detecting true ADL and 2o driving, a lower threshold will detect most ADL as well as driving while a higher threshold will detect lesser driving and true ADL.
ADL3: This algorithm is similar to ADL2 except for the choice of window. Since we do not have any a priori knowledge of the typical duration of activities of daily living, a choice of 40 seconds was made in order to study the difference in 25 performance between the 80 second and the 40 second windows.
ADL4: As described above, ADLl, ADL2 and ADL3 are threshold algorithms and do not attempt to separate out non-activities from activities based on variability (only amplitude information is used). In the ADL4 algorithm, the 80 second average is first calculated. The number of 2 second counts that are greater than 0 3o are also noted. If the 80 second average is greater than 1.0 and at least second counts in the 80 second window are greater than 0, then the 80 second window is detected as ADL.
ADLS: This algorithm is another way to use the variability information. The 80 second window is separated into 20 second sub-windows and the average for the s second window as well as the 4 sub-windows are calculated. If the average of the 80 second window is greater than 1.0 and 3/4 sub-window averages are greater than 0.3 *(average of 80 second window), then the 80 second window is detected as ADL.
t o Algorithm Evaluation The 24 hour data set we used was collected from 10 normal subjects and separated into two groups, a Development data set and a Validation data set. Three performance measures P 1, P2 and P3 were calculated for each data set in the ~5 Development data set. Algorithm parameters were adjusted to achieve the highest P1 and P2, and lowest P3. Since these performance measures are different from the traditional sensitivity and specificity measures used to evaluate algorithms, each of these measures is defined and explained below.
Performance measure P1 PI =
Duration of marked ADL that is detected by al orithm) Duration of marked ADL as marked by subject (gold standard) We had the normal subjects mark those times they felt they were active. Upon close inspection of the marked ADL, it was found that several marked ADL
events were of the stop-go-stop-go type, i.e., there were periods of rest in between short bouts of activity, which is characteristic of activities of daily living. In order not to 3o penalize the algorithm for the detection of rest periods in between marked ADLs, only that part of marked ADL that was associated with an elevated heart rate ( heart rate during rest period during day + 10 bpm) was considered as marked ADL.
This procedure can be thought of as refining the gold standard data.
s Performance measure P2 This measure was used to ascertain whether the algorithm was detecting non-activities as ADL. Since not all activities and non-activities are marked, a heart rate based criterion was used to differentiate between activities and non-activities.
Specifically, activities that were associated with a elevated heart rate (resting heart rate during day + 10 bpm).
P2 =
Total time detected as ADL associated with a elevated heart rate (P2N) is Total time detected as ADL (P2D) For example, to calculate P2 from a 24 hour data set, P2D is calculated as the # of 80 second activity windows detected as ADL by the algorithm. To calculate P2N, 2o the heart rate in the 80 second window corresponding to the 80 second activity window that is detected as an ADL is calculated first. If the heart rate in this window is above (rest heart rate + 10 bpm), then the 80 second activity window is said to be appropriately detected. The ratio of P2N and P2D is the performance measure P2.
2s Performance measure P3 This measure is used to ascertain the ability of the algorithm to eliminate detection of automobile driving as ADL. Automobile driving (or riding in a bumpy 3o conveyance of any type) we believe will be one of the main causes of false positives. This measure P3 is calculated as the ratio of P3N and P3D, where P3D is the total duration of marked driving by the normal subject and P3N is the duration during which marked driving was detected as ADL. Clearly, the lower P3 is, the better the algorithm.
P3 =
_ Total driving time that is detected as ADL (P3N) Total marked driving time (P3D) Calculation of heart rate To obtain heart rate data, 24 hour surface ECG data stored in a Holter Monitor system were downloaded and analyzed using "Hotter for Windows"(TM) software (available through Rozin Electronics, Glendale NY). Every beat of the ECG data (each beat corresponds to the detection of a QRS complex) was classified as a Normal beat, Ventricular beat, Supra-ventricular beat or an Artifact. Only intervals ~5 between normal (sinus) beats (referred to as NN intervals) were used to compute heart rates during the entire 24 hour period.
The accelerometer signal is processed and a raw count is calculated every 2 seconds (ACTCNT) for pacemaker rate response. An algorithm to calculate minutes of ADL
2o from ACTCNT is as follows:
[Where NUM is the total number of activity counts, THRESH is the threshold for whether the activity count value will be counted as a one or a zero in the SUM
of counts, and DAILYCOUNT is the variable value to be displayed for a single day.
It should be noted that if the values of a week of DAILYCOUNTs are averaged to 2s provide a single point to display as was the case for the graphs of Figs. 1-5, the average value will be what is displayed, but for more detailed analysis, even if averaging is used, the DAILYCOUNT values would preferably be retained beyond a given week, unless the device in question is operating with minimal memory capacity.

Step i . Starting at 12 a. m. (00:00:00), add NUM ACTCNT, i.e., SUM = S ACTCNT/ NUM.
s Step 2. If SUM > THRESH, increment a counter (DAILYCOUNT) else next step.
Step 3. Repeat Step 1 and 2 continuously till the next 12 midnight Step 4. Save DAILYCOUNT for this day and repeat Steps 1-4 to If averaging over a larger period, average the DAILY COUNT values for the past number of days in the period and establish a larger value representing the average, AVDAILYCOUNT for the period, so that that value AVDAILYCOUNT can be displayed.
NUM and THRESH are 1 byte programmable Recommended values are NUM = 30, THRESH = 45 2o Memory requirements:
For NUM = 30, DAILYCOUNT could have a maximum value of 1440 and would require 2 bytes of storage every day.
Total memory: 2 bytes a day (850 bytes for 425 days) Software algorithm and printing Step 1. ADLDAY = DAILYCOUNT * NUM * 2 / 60 3o Step 2. ADL= Avg. ( 7 consecutive ADLDAY ) Graph ADL every week as illustrated in "Long Term Clinical Trends "
Y axis title: "Total hours of patient activity per day"
Y axis tick labels: " 0 2 4 > 6 " Hours s Algorithm Evaluation As detailed above, each of the 5 candidate algorithms were applied to each of the 5 data sets in the Development data set and the three performance measures Pl, and P3 calculated. The algorithm parameters were changed to maximize P1 and P2 1 o and minimize P3. The values and brief descriptions of Pl , P2 and P3 for each of these 5 normals is shown in Table 2. Following algorithm development, the algorithms were applied to the Validation data set and the process repeated.
Table 3 shows the performance measures for the Validation data set. It is important to note that the utility of the performance measures is limited to the comparison of the 1s different algorithms only and is not meant to be used as an absolute measure of sensitivity and specificity.
As detailed in the Methods section, each of the 5 candidate algorithms were applied to each of the 5 data sets in the Development data set and the three performance 2o measures P 1, P2 and P3 calculated. The algorithm parameters were changed to maximize P1 and P2 and minimize P3. The values and brief descriptions of P1, and P3 for each of these 5 normals is shown in Table 2. Following algorithm development, the algorithms were applied to the Validation data set and the process repeated. Table 3 shows the performance measures for the Validation data set.
It is 2s important to note that the utility of the performance measures is limited to the comparison of the different algorithms only and is not meant to be used as an absolute measure of sensitivity and specificity.

pl ~ P3 ADL1 70 % 86 % 28 %

ADL2 62 % 91 % 20 ADL3 60 % 89 % - 20 ADL4 72 % 86 % 42 %

ADLS 65 % 87 % 36 Pl: Ability of the algorithm to detect marked ADL activities P2: Ability of the algorithm to detect activities that are associated with an increase in heart rate P3: Ability of the algorithm to detect automobile driving.
Table 2. Performance measures for Development data set pl pZ P3 ADLl 72 % 80 % 24 %

ADL2 66 % 85 % 14 %

ADL3 63 % 84 % 14 ADL4 74% $0% 36%

ADLS 66 % g0 % 28 1o Table 3. Performance measures for Validation data set Several observations can be made from these results. Given that the goal of the algorithm is to maximizx P1 and P2 and minimize P3, it is clear from Table 3 that algorithm ADL1 and ADL2 best meet the criteria. The only difference between ADL1 and ADL2 is the threshold parameter, ADL1 had a threshold of 1.5 and s ADL2 had a threshold of 2Ø It is to be expected that a higher threshold (ADL2) would lead to a decreased sensitivity (P1 is lower for ADL2) and but increased specificity (P2 is higher for ADL2). The only difference between ADL2 and ADL3 is the choice of window (ADL2 used a 80s window while ADL3 used a 40s window). Based on the results, it appears that decreasing the window from 80s to 40s had a minimal effect on the performance measures. This may be because most ADL may have been longer than 40 seconds. The variability algorithms do not appear to detect driving any less than the threshold type algorithms. This may be because of the fact that the variability of driving while evident in the 2 second data may not be a factor when data is averaged over 80 seconds. Table 3 shows the ~s . ~ performance for the Validation data set. The results from the Validation data set are consistent with the observations made from the Development data set.
Based on these observations, ADL1 (essentially same as ADL2) algorithm was chosen as the algorithm of choice since this algorithm has the highest sensitivity for 2o marked ADL activities. Coincidentally, this algorithm is associated with the least implementation complexity.
Comparison of ADL between normals and heart failure patients As explained in the Data Collection section, 24 hour activity and heart rate data 2s were collected from 10 heart failure patients as part of the EXACT study in addition to the 10 normal subjects as part of the Normal study. Such data were collected 7 times from each patient over a period of 16 weeks. However, detailed diary data were not collected from the patients as was from the normal subjects. Even though the 24 hour EXACT data from the patients do not lend themselves to the type of analysis performed on the data from normal subjects, these data were used to study algorithm performance in two different ways.
Thirty (30) data sets, each consisting of 24 hour heart rate and activity data from a s patient were analyzed using algorithm ADL1. At the beginning of the 24 hour follow-up, each patient undergoes a 10 minute rest period and a 6 minute walking test. Each of these two events are marked using the DR180 Holter apparatus.
Based on these data 29/30 waking activities ( 6 minute walks) were detected successfully and none of the 30 rest periods were detected. The only activity episode not to detected by the algorithm was the 6 minute walk from Patient 2, Baseline Evaluation. On closer inspection of the data, it was found that this patient was walking extremely slowly (40 steps per minute). However, the 6 minute walk from the same patient during her subsequent follow-ups were detected appropriately, because she walked faster than 40 steps per minute.
Another way of using the 24 hour data from heart failure patients is to compare the total ADL/per day from the heart failure patients with the normal subjects.
Figure 14 shows the daily activities (hours:minutes) for each of the 10 normal subjects and 30 data sets from heart failure patients. Mean ADL/day was 4 hours 51 minutes in 2o Normal subjects and is significantly greater than ADL/day of 2 hours and 10 minutes of the heart failure patients. Even though this result is not unexpected (one would expect the normal subjects to be more active than the heart failure patients) and the normal subjects are not age matched, it does provide a "reality check"
of the algorithm. In fact, one may argue that the ability to separate out normal subjects from heart failure subjects based on their activities is a desired attribute of an algorithm.
The general approach.
3o The algorithm accepts the filtered activity count for a two second interval. As mentioned previously, this is bandpassed data from a sensor such as an accelerometer that measures a count every time it moves. Various forms of activity sensor could be used which would require different pre processing. For example, if a three axis accelerometer were used, one could filter out or ignore the activity occurring outside of a particular plane of acceptable motion; such that a patient s moving up and down would register a count, but one moving sideways may not.
Alternatively only large excursions in signal output indicating a movement or shock of a sufficient size could be employed, thereby removing small movements form the calculation. If motion is detected from changes in a resonant microbeam sensor due to stress or pressure, different pre filtering schema must likewise be adopted. What is essential is that a mechanism be adopted to generate a count that gives a rough absolute value range for the amount of movement or change experienced by the sensor over a short period of time, and that this value then be averaged or otherwise compared to the other short period activity values collected over a larger period of time. In our preferred embodiment we used 2 seconds for the short period and one ~5 minute for the long period because of convenience, but any vaguely similar pair could be used, for examples, one second short over 2 minute long periods, or thirty second short over half hour long periods., One could even name the long periods to correspond to day times to produce a display color or three dimensions with values for the activity counts per hour displaying more toward the red side of a spectrum 2o for higher activity and more toward the blue for less, or vice versa, thus providing a . diurnal chart.
While all these variations and more will naturally occur to one of ordinary skill in this art, we have found it to be perfectly acceptable to use a single axis 25 accelerometer or piezocrystal with a value of 1.5 counts per minute as reasonable for cardiac patients. The amount of activity of a cardiac patient will generally be quite low on average and we want to pick up even small activities in the case of the CHF patient. Our studies indicated that an activity level of a 95 steps per minute over the minutes walked of a healthy person was about 23, but at 60 steps per 3o minute the average count was more like 5 or 8 counts per walked minute.
Since the CHF patient will be doing few walks of more than a minute the expectation is that nearly all two second periods will register a zero activity signal, which was born out through experiment. However, it should be recognized that if the small period chosen is larger, or the activity sensor more sensitive than what we used, a larger count may be expected, possibly necessitating an adjustment in the exclusion level above what we chose as 1.5 average counts per minute period. Similar adjustments to this value will occur to the reader without the need for undue experimentation.
So in general, in our preferred embodiment, to find the number of active 1 minute periods in a 24 hour period, a raw activity count is established for each two second Io period. To capture the patient in ADL, we use an average of 1.5 activity counts for each of the 2 second periods in a minute. Thus if the sum of activity counts in a minute, divided by the number of short periods is greater than 1.5, we declare the minute containing these short periods "active" . We then do this for a 24 hour period and add up the active periods to get our chartable data point. We could use is some other mathemetal function besides averaging, such as to pick the mean or maximum value, but these while possibly acceptable are less preferred. Many other well known mathematical functions could be used within the skill of the practitioner of this art to substitute for average if desired.
2o Therefore, in general, we are figuring on the basis of the number of short periods (like a 2 second interval), that a patient is determined to be active over the course of a first larger period, one can thus establish a clinically valuable data set of larger period activity that corresponds to the medically recognized functional status of the patient. In our preferred algorithms, we employed two period sizes larger than the 2s first larger period just mentioned to refine the available data and produce an easily useable display. The period larger than the first larger period is a day, in our preferred embodiments. Thus the number of active first larger periods in a day can easily be tallied and displayed as a percentage or number of hours in the day period.
In our most preferred embodiment, we average the value established each day over 3o a week, which allows for what we believe to be more useful information to be WO 99/58056 PC'f/US99/10282 displayed, since patient activity is normally quite variable over the course of a week and also so that a smaller display can be used for a large set of data.
Because this can be confusing, we use the following example for a detailed s discussion of the application of the concept for a 2-second count set over a minute period.
EXAMPLE 1.
cs = counts /2sec. period ~o If cs is an element of the set containing the count values for each 2 second period in a minute, i.e., {0,0,0,0,1,0,0,15,30,32,10,2,0,0,1,0,0,0,0,0,0,0,01,0,2,1,0,0,0}, then the average value (the sum of the elements' values divided by the number 30), then the value for that minute is approximately 2.7, which is greater than the 1.5 we 1s are using for the cut-off point, so a positive activity value gets recorded for this minute.
EXAMPLE 2.
if cs = counts/2 second period and If cs is an element of the set containing the count values for each 2 second 2o period in a minute, i.e., {0,0,0,0,0,0,1,0,0,0,1,0,0,1,5,3,2,0,0,0,0,2,8 ,0,0,0,0, ,3,0,1,0,0},then the average value (the sum of the elements' values divided by the number 30), for that minute is less than 1 so a negative or zero activity attribute is stored for that minute.
25 Depending on the kind of display desired, we can telemeter or otherwise communicate the data from an implanted device monitoring activity data in the way we describe which includes any subset of the data or all of it. Preferably a display of the amount of activity in a day, averaged over a week will be displayed for a number of months in a display similar to the graphs illustrated in Figs. 1-5.
3o Additionally, this data can be printed out for storage and later use by reference to a patient's file.

WO 99/58056 PG"fNS99/10282 Many adaptations can be made upon the information provided by this invention.
For one thing, a patient alarm may be sounded to incent the patient to comply with an exercise regimen or to call his doctor. Today small and low power piezo speakers with small speech producing circuitry are plentiful and inexpensive.
The data here if it shows a failure or inability of the patient to comply with an exercise regimen could actually speak to the patient and say things like, 'time to get on the treadmill' or 'time to go to the doctor' or something similar, based on the severity of the failure of the patient to achieve the activity goals set with his physician and to programmed into the device. Additional patient signals like a buzzer, shaker, or even electric shock could be provided to get the patient's attention. As already mentioned, if a particular activity pattern is developing, and this device is included in a drug pump, the drugs the patient is receiving could be adjusted based on his activity level, the angle of its downward or upward slope, or other characteristics is determinable based on this activity data set.
Also, if the device records arrhythmias sensed through auto triggering mechanisms or through patient activation of the event record we can report this data out with an indication of it's temporal correspondence to activity level. This can tell the 2o physician whether the arrhytmia occurred during rest or activity.
Arrhythmia monitoring background art, hereby incorporated by this reference includes US
patents numbered 5,113,869; 5,313,953; and 5,086,772. Also incorporated by reference are the following patents on triggering recordings of arrhythmic events, both automatically and by patient activation; 4,086,916; 5,404,877 and 5,012,814.
Another less preferred embodiment would be to use an external device strapped or otherwise affixed to a patient's body to collect the activity data, (requiring of course some adjusment to the prederemined value for deciding whether a minute period qualified to be called active), but considering the difficulty in gaining paitient 3o compliance or comfort, we feel the implantable versions will be most effications.

Many variations on the teachings of this invention may fall within its ambit, but the invention is only limited by the following claims.

Claims (27)

Claims:
1. An implantable medical device for tracking patient functional status comprising a housing having an activity sensor and circuitry therein for recording output from said activity sensor such that said output is compressed in accord with a processing circuit constructed to operate a procedure to iteratively, after the expiry of each of a first size time interval to:
add up via a summation means a number of activity counts sensed per a first one of each first time intervals to produce a first sum, and if said first sum is greater than a predetermined value, storing a count value representing the result of comparing said first time interval first sum to said predetermined value in a memory means, then to repeat this add up procedure for subsequent ones of said first size intervals and storing a count value for said first size time intervals until a second size time interval is reached, then to determine via a computation means a first display value for a representation of said recorded first and second values, and storing said first display value representing said total value for each said second time interval.
2. A device as set forth in claim 1 further comprising means for providing said first display values to a display means for displaying a second display value wherein a sum of said first display values.
3. A device as set forth in claim 1 wherein said processing circuit is adapted to further iteratively determine if said first display value is a predetermined function of a predetermined alarm value, and for storing a result of said determination, then setting an alarm flag representing the result of said determination.
4. A device as set forth in claim 3 wherein said alarm value flag activates a patient alarm to notify the patient.
5. A device as set forth in claim 4 wherein said patient alarm is an audible sound generator.
6. A device as set forth in clam 5 wherein said audible sound generator is adapted to produce intelligible speech.
7. A device as set forth in claim 1 wherein said processing circuit is adapted to further determine if activity values represented by said first display values match a programmable pattern of activity level, and to set a flag indicating such a change.
8. A medical information display system for use with a device as set forth in claims 1 or 3-7 having means to receive data from said implantable device memory and processing means for generating a display, such that said display may display a representation of said first display values in a manner such that said first display correspond to the height on an axis parallel to patient status, and wherein said display has a perpendicular axis for displaying a progression of heights of said first display values for a first time unit varying over a time period comprised of multiple time units.
9. A device as set forth in claim 8 wherein said processing circuit of said display means is further adapted to average all said second values over an intermediate period of time such that said display of said first display values is represented by a single value for said intermediate time.
10. A device as set forth in claim 1 wherein said device housing further has additional sensor means for measuring values of additional physiologic parameters of a patient into which said device may be implanted and producing measurement output therefrom, and wherein said circuitry for processing and storing values processes and stores temporally related to said first first display values, additional physiologic measurement values taken from said additional sensor means output.
11. A device as set forth in claim 10 wherein said additional sensors sense physiologic signals including those drawn from the set of signals (arrhythmias, arrhythmias during rest periods, respiration rate during rest periods, respiration rate, occurrence of abnormal breathing episodes during rest, change in sinus rate during rest, heart rate variability, blood pressure, ST segment variation, blood oxygenation, temperature).
12. A medical system as set forth in claim 8 further comprising a receiving device for receiving patient data from said implant including representations of said first display values having a communications link to a communications system to enable the communication of said representation of said first display values to a remote device for subsequent display.
13. A method of tracking patient functional status comprising:
measuring activity counts with an implantable activity sensor, recording output from said activity sensor such that said output is compressed in accord with a procedure which iteratively, after the expiry of each of a first size time interval:
adds up a number of activity counts sensed per a first one of each first time intervals to produce a first sum, and if said first sum is greater than a predetermined value, storing a count value representing the result of comparing said first time interval first sum to said predetermined value in a memory means, then repeating this add up procedure for subsequent ones of said first size intervals and storing a count value for said first size time intervals until a second size time interval is reached, then determining a first display value for a representation of said recorded first and second values, and storing said first display value representing said total value for each said second time interval.
14. A method as set forth in claim 13 further comprising providing said first display values to a display means and then displaying a second display value comprising a representation of a sum of said first display values for a diurnal time period.
15. A method as set forth in claim 13 comprising the additional steps of further iteratively determining if said first display value is a predetermined function of a predetermined alarm value, and for storing a result of said determination, then setting an alarm flag representing the result of said determination.
16. A method as set forth in claim 13 wherein if said alarm value flag is set, activating a patient alarm to notify the patient.
17. A method for displaying representations of said first display values generated by any of the methods as set forth in claims 13 or 14-17 further comprising the step of receiving said first display values for generating a display, and adding up all the first display values for a diurnal period and displaying a visual representation of said value of said sum for each said diurnal period in a range of diurnal periods.
18. A method as set forth in claim 17 comprising the intermediate step of averaging all said diurnal period values for a week and then displaying a visual representation of the value of the week average for the week.
19. A method as set forth in claim 13 further comprising communicating the first display values to an external device.
20. A method as set forth in claim 19 further comprising activating an alarm system in said external device for setting a flag to take corrective action if the display values match a predetermined pattern.
21. A method as set forth in claim 17 further comprising titrating patient medication levels based on review of the display.
22. A device as set forth in claim 1 wherein said device housing further has additional sensor means for measuring values of additional physiologic parameters of a patient into which said device may be implanted and producing measurement output therefrom, and wherein said circuitry for processing and storing values processes and stores temporally related to said first first display values, additional physiologic measurement values taken from said additional sensor means output.
23. A medical system as set forth in claims 1-11 or 22 further comprising a receiving device for receiving patient data from said implant including representations of said first display values having a communications link to a communications system to enable the communication of said representation of said first display values to a remote device for subsequent display.
24. An implantable medical device comprising means for tracking activity counts over a small unit of time and for storing a compilation of values related to the combined sums of said activity counts for the sum of small units of time over a larger unit of time and having means for recording arrhythmic cardiac events such that data from said compilation of values is stored with an indication of temporal relatedness to any arrhythmic events which occur near in time to said compilation of values being a predetermined value.
25 An implantable medical device having an activity crystal for determining a counts value for each "a" second period, a processing circuit for averaging each said counts value over the number of a second counts in each minute, and having a memory circuit for storing a positive activity value for said average counts value for each minute if said average counts value is greater than a predetermined value.
26. An implantable medical device as set forth in claim 25 further comprising a processing circuit for storing the sum of all said positive activity values.
27. A device affixed to a patient for tracking patient functional status comprising a housing having an activity sensor and circuitry therein for recording output from said activity sensor such that said output is compressed in accord with a processing circuit constructed to operate a procedure to iteratively, after the expiry of each of a first size time interval to:
add up via a summation means a number of activity counts sensed per a first one of each first time intervals to produce a first sum, and if said first sum is greater than a predetermined value, storing a count value representing the result of comparing said first time interval first sum to said predetermined value in a memory means, then to repeat this add up procedure for subsequent ones of said first size intervals and storing a count value for said first size time intervals until a second size time interval is reached, then to determine via a computation means a first display value for a representation of said recorded first and second values, and storing said first display value representing said total value for each said second time interval.
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Families Citing this family (294)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6129744A (en) * 1997-12-04 2000-10-10 Vitatron Medical, B.V. Cardiac treatment system and method for sensing and responding to heart failure
US6821249B2 (en) * 1999-03-08 2004-11-23 Board Of Regents, The University Of Texas Temperature monitoring of congestive heart failure patients as an indicator of worsening condition
US20070021979A1 (en) * 1999-04-16 2007-01-25 Cosentino Daniel L Multiuser wellness parameter monitoring system
US20060030890A1 (en) * 1999-04-16 2006-02-09 Cosentino Daniel L System, method, and apparatus for automated interactive verification of an alert generated by a patient monitoring device
US8419650B2 (en) 1999-04-16 2013-04-16 Cariocom, LLC Downloadable datasets for a patient monitoring system
US8438038B2 (en) * 1999-04-16 2013-05-07 Cardiocom, Llc Weight loss or weight management system
US7577475B2 (en) * 1999-04-16 2009-08-18 Cardiocom System, method, and apparatus for combining information from an implanted device with information from a patient monitoring apparatus
US7945451B2 (en) * 1999-04-16 2011-05-17 Cardiocom, Llc Remote monitoring system for ambulatory patients
US6290646B1 (en) 1999-04-16 2001-09-18 Cardiocom Apparatus and method for monitoring and communicating wellness parameters of ambulatory patients
US6294993B1 (en) * 1999-07-06 2001-09-25 Gregory A. Calaman System for providing personal security via event detection
CA2314517A1 (en) 1999-07-26 2001-01-26 Gust H. Bardy System and method for determining a reference baseline of individual patient status for use in an automated collection and analysis patient care system
US6493579B1 (en) * 1999-08-20 2002-12-10 Cardiac Pacemakers, Inc. System and method for detection enhancement programming
US6289248B1 (en) 1999-08-20 2001-09-11 Cardiac Pacemakers, Inc. System and method for detecting and displaying parameter interactions
US6454705B1 (en) 1999-09-21 2002-09-24 Cardiocom Medical wellness parameters management system, apparatus and method
EP1217942A1 (en) 1999-09-24 2002-07-03 Healthetech, Inc. Physiological monitor and associated computation, display and communication unit
US7127290B2 (en) 1999-10-01 2006-10-24 Cardiac Pacemakers, Inc. Cardiac rhythm management systems and methods predicting congestive heart failure status
AU8007600A (en) 1999-10-08 2001-04-23 Healthetech, Inc. Monitoring caloric expenditure rate and caloric diet
US6453201B1 (en) 1999-10-20 2002-09-17 Cardiac Pacemakers, Inc. Implantable medical device with voice responding and recording capacity
US6409675B1 (en) * 1999-11-10 2002-06-25 Pacesetter, Inc. Extravascular hemodynamic monitor
US6336903B1 (en) * 1999-11-16 2002-01-08 Cardiac Intelligence Corp. Automated collection and analysis patient care system and method for diagnosing and monitoring congestive heart failure and outcomes thereof
US6752765B1 (en) 1999-12-01 2004-06-22 Medtronic, Inc. Method and apparatus for monitoring heart rate and abnormal respiration
US6513532B2 (en) * 2000-01-19 2003-02-04 Healthetech, Inc. Diet and activity-monitoring device
EP1118307B1 (en) * 2000-01-19 2007-10-24 Pacesetter, Inc. An implantable cardiac device for monitoring progression or regression of heart disease
US6438407B1 (en) 2000-03-20 2002-08-20 Medtronic, Inc. Method and apparatus for monitoring physiologic parameters conjunction with a treatment
US6482158B2 (en) 2000-05-19 2002-11-19 Healthetech, Inc. System and method of ultrasonic mammography
US6659968B1 (en) * 2000-06-01 2003-12-09 Advanced Bionics Corporation Activity monitor for pain management efficacy measurement
EP1358745B1 (en) * 2000-08-22 2008-12-10 Medtronic, Inc. Medical device systems implemented network system for remote patient management
US6607387B2 (en) 2000-10-30 2003-08-19 Healthetech, Inc. Sensor system for diagnosing dental conditions
US20020055857A1 (en) * 2000-10-31 2002-05-09 Mault James R. Method of assisting individuals in lifestyle control programs conducive to good health
DE60035719T2 (en) 2000-11-17 2008-04-30 Medtronic, Inc., Minneapolis Device for monitoring heart rate and abnormal ventilation
US6741885B1 (en) 2000-12-07 2004-05-25 Pacesetter, Inc. Implantable cardiac device for managing the progression of heart disease and method
US7181285B2 (en) 2000-12-26 2007-02-20 Cardiac Pacemakers, Inc. Expert system and method
US7052466B2 (en) 2001-04-11 2006-05-30 Cardiac Pacemakers, Inc. Apparatus and method for outputting heart sounds
US6636762B2 (en) 2001-04-30 2003-10-21 Medtronic, Inc. Method and system for monitoring heart failure using rate change dynamics
US6675044B2 (en) * 2001-05-07 2004-01-06 Medtronic, Inc. Software-based record management system with access to time-line ordered clinical data acquired by an implanted device
EP1256316A1 (en) * 2001-05-07 2002-11-13 Move2Health B.V. Portable device comprising an acceleration sensor and method of generating instructions or advice
US20030050566A1 (en) * 2001-09-07 2003-03-13 Medtronic, Inc. Arrhythmia notification
US8224663B2 (en) * 2002-05-24 2012-07-17 Becton, Dickinson And Company System and method for assessment and corrective action based on guidelines
US7383088B2 (en) * 2001-11-07 2008-06-03 Cardiac Pacemakers, Inc. Centralized management system for programmable medical devices
NO20016385L (en) * 2001-12-27 2003-06-30 Medinnova Sf System for monitoring heart rate changes, preferably a heart muscle
US20030125662A1 (en) * 2002-01-03 2003-07-03 Tuan Bui Method and apparatus for providing medical treatment therapy based on calculated demand
US6980112B2 (en) * 2002-01-08 2005-12-27 International Business Machines Corporation Emergency call patient locating system for implanted automatic defibrillators
US8043213B2 (en) * 2002-12-18 2011-10-25 Cardiac Pacemakers, Inc. Advanced patient management for triaging health-related data using color codes
US8391989B2 (en) 2002-12-18 2013-03-05 Cardiac Pacemakers, Inc. Advanced patient management for defining, identifying and using predetermined health-related events
US7043305B2 (en) 2002-03-06 2006-05-09 Cardiac Pacemakers, Inc. Method and apparatus for establishing context among events and optimizing implanted medical device performance
US7468032B2 (en) 2002-12-18 2008-12-23 Cardiac Pacemakers, Inc. Advanced patient management for identifying, displaying and assisting with correlating health-related data
US20040122487A1 (en) 2002-12-18 2004-06-24 John Hatlestad Advanced patient management with composite parameter indices
US20040122296A1 (en) * 2002-12-18 2004-06-24 John Hatlestad Advanced patient management for triaging health-related data
US7983759B2 (en) 2002-12-18 2011-07-19 Cardiac Pacemakers, Inc. Advanced patient management for reporting multiple health-related parameters
US20040122486A1 (en) * 2002-12-18 2004-06-24 Stahmann Jeffrey E. Advanced patient management for acquiring, trending and displaying health-related parameters
US20040122294A1 (en) 2002-12-18 2004-06-24 John Hatlestad Advanced patient management with environmental data
US7039462B2 (en) * 2002-06-14 2006-05-02 Cardiac Pacemakers, Inc. Method and apparatus for detecting oscillations in cardiac rhythm
US7113825B2 (en) 2002-05-03 2006-09-26 Cardiac Pacemakers, Inc. Method and apparatus for detecting acoustic oscillations in cardiac rhythm
US7110823B2 (en) * 2002-06-11 2006-09-19 Advanced Bionics Corporation RF telemetry link for establishment and maintenance of communications with an implantable device
US20030126593A1 (en) * 2002-11-04 2003-07-03 Mault James R. Interactive physiological monitoring system
US7072711B2 (en) 2002-11-12 2006-07-04 Cardiac Pacemakers, Inc. Implantable device for delivering cardiac drug therapy
US7986994B2 (en) 2002-12-04 2011-07-26 Medtronic, Inc. Method and apparatus for detecting change in intrathoracic electrical impedance
US7191006B2 (en) * 2002-12-05 2007-03-13 Cardiac Pacemakers, Inc. Cardiac rhythm management systems and methods for rule-illustrative parameter entry
AU2003280131A1 (en) * 2002-12-10 2004-06-30 Koninklijke Philips Electronics N.V. Activity monitoring
WO2004052203A1 (en) * 2002-12-10 2004-06-24 Koninklijke Philips Electronics N.V. Activity monitoring
US20050080348A1 (en) * 2003-09-18 2005-04-14 Stahmann Jeffrey E. Medical event logbook system and method
US8951205B2 (en) 2002-12-30 2015-02-10 Cardiac Pacemakers, Inc. Method and apparatus for detecting atrial filling pressure
US7972275B2 (en) 2002-12-30 2011-07-05 Cardiac Pacemakers, Inc. Method and apparatus for monitoring of diastolic hemodynamics
US7378955B2 (en) 2003-01-03 2008-05-27 Cardiac Pacemakers, Inc. System and method for correlating biometric trends with a related temporal event
US7136707B2 (en) 2003-01-21 2006-11-14 Cardiac Pacemakers, Inc. Recordable macros for pacemaker follow-up
US6915157B2 (en) * 2003-02-18 2005-07-05 Medtronic, Inc. Implantable medical device for assessing heart failure state from Mechanical Pulsus Alternans
US6887207B2 (en) 2003-02-26 2005-05-03 Medtronic, Inc. Methods and apparatus for estimation of ventricular afterload based on ventricular pressure measurements
US20040199056A1 (en) * 2003-04-03 2004-10-07 International Business Machines Corporation Body monitoring using local area wireless interfaces
US20040230456A1 (en) * 2003-05-14 2004-11-18 Lozier Luke R. System for identifying candidates for ICD implantation
US7477932B2 (en) * 2003-05-28 2009-01-13 Cardiac Pacemakers, Inc. Cardiac waveform template creation, maintenance and use
US7539803B2 (en) * 2003-06-13 2009-05-26 Agere Systems Inc. Bi-directional interface for low data rate application
US7177684B1 (en) 2003-07-03 2007-02-13 Pacesetter, Inc. Activity monitor and six-minute walk test for depression and CHF patients
US8251061B2 (en) * 2003-09-18 2012-08-28 Cardiac Pacemakers, Inc. Methods and systems for control of gas therapy
US7575553B2 (en) * 2003-09-18 2009-08-18 Cardiac Pacemakers, Inc. Methods and systems for assessing pulmonary disease
US8002553B2 (en) 2003-08-18 2011-08-23 Cardiac Pacemakers, Inc. Sleep quality data collection and evaluation
US7678061B2 (en) 2003-09-18 2010-03-16 Cardiac Pacemakers, Inc. System and method for characterizing patient respiration
US7572225B2 (en) * 2003-09-18 2009-08-11 Cardiac Pacemakers, Inc. Sleep logbook
US7610094B2 (en) * 2003-09-18 2009-10-27 Cardiac Pacemakers, Inc. Synergistic use of medical devices for detecting medical disorders
US7967756B2 (en) * 2003-09-18 2011-06-28 Cardiac Pacemakers, Inc. Respiratory therapy control based on cardiac cycle
US7396333B2 (en) * 2003-08-18 2008-07-08 Cardiac Pacemakers, Inc. Prediction of disordered breathing
US7887493B2 (en) 2003-09-18 2011-02-15 Cardiac Pacemakers, Inc. Implantable device employing movement sensing for detecting sleep-related disorders
US7668591B2 (en) * 2003-09-18 2010-02-23 Cardiac Pacemakers, Inc. Automatic activation of medical processes
US7662101B2 (en) * 2003-09-18 2010-02-16 Cardiac Pacemakers, Inc. Therapy control based on cardiopulmonary status
US20050142070A1 (en) * 2003-09-18 2005-06-30 Hartley Jesse W. Methods and systems for assessing pulmonary disease with drug therapy control
EP1670547B1 (en) 2003-08-18 2008-11-12 Cardiac Pacemakers, Inc. Patient monitoring system
US8396565B2 (en) * 2003-09-15 2013-03-12 Medtronic, Inc. Automatic therapy adjustments
US7286872B2 (en) * 2003-10-07 2007-10-23 Cardiac Pacemakers, Inc. Method and apparatus for managing data from multiple sensing channels
US7937149B2 (en) * 2003-12-03 2011-05-03 Medtronic, Inc. Method and apparatus for detecting change in physiologic parameters
US20050137629A1 (en) * 2003-12-08 2005-06-23 Dyjach John A. Trended measurement of cardiac resynchronization therapy
US20060247693A1 (en) 2005-04-28 2006-11-02 Yanting Dong Non-captured intrinsic discrimination in cardiac pacing response classification
US7319900B2 (en) * 2003-12-11 2008-01-15 Cardiac Pacemakers, Inc. Cardiac response classification using multiple classification windows
US8521284B2 (en) 2003-12-12 2013-08-27 Cardiac Pacemakers, Inc. Cardiac response classification using multisite sensing and pacing
US7774064B2 (en) * 2003-12-12 2010-08-10 Cardiac Pacemakers, Inc. Cardiac response classification using retriggerable classification windows
US8589174B2 (en) * 2003-12-16 2013-11-19 Adventium Enterprises Activity monitoring
US7471980B2 (en) * 2003-12-22 2008-12-30 Cardiac Pacemakers, Inc. Synchronizing continuous signals and discrete events for an implantable medical device
US7115096B2 (en) * 2003-12-24 2006-10-03 Cardiac Pacemakers, Inc. Third heart sound activity index for heart failure monitoring
ATE536801T1 (en) * 2004-01-15 2011-12-15 Koninkl Philips Electronics Nv ADAPTIVE PHYSIOLOGICAL MONITORING SYSTEM AND METHOD OF USE THEREOF
US7232435B2 (en) * 2004-02-06 2007-06-19 Medtronic, Inc. Delivery of a sympatholytic cardiovascular agent to the central nervous system to counter heart failure and pathologies associated with heart failure
US20050192487A1 (en) * 2004-02-27 2005-09-01 Cosentino Louis C. System for collection, manipulation, and analysis of data from remote health care devices
US8894576B2 (en) * 2004-03-10 2014-11-25 University Of Virginia Patent Foundation System and method for the inference of activities of daily living and instrumental activities of daily living automatically
US8308661B2 (en) 2004-03-16 2012-11-13 Medtronic, Inc. Collecting activity and sleep quality information via a medical device
US7395113B2 (en) * 2004-03-16 2008-07-01 Medtronic, Inc. Collecting activity information to evaluate therapy
US8055348B2 (en) 2004-03-16 2011-11-08 Medtronic, Inc. Detecting sleep to evaluate therapy
US8725244B2 (en) * 2004-03-16 2014-05-13 Medtronic, Inc. Determination of sleep quality for neurological disorders
US20070276439A1 (en) * 2004-03-16 2007-11-29 Medtronic, Inc. Collecting sleep quality information via a medical device
US7542803B2 (en) * 2004-03-16 2009-06-02 Medtronic, Inc. Sensitivity analysis for selecting therapy parameter sets
US7805196B2 (en) 2004-03-16 2010-09-28 Medtronic, Inc. Collecting activity information to evaluate therapy
EP1849412B1 (en) * 2004-03-16 2009-03-04 Medtronic, Inc. Collecting activity information to evaluate therapy
US20050209512A1 (en) * 2004-03-16 2005-09-22 Heruth Kenneth T Detecting sleep
US7366572B2 (en) * 2004-03-16 2008-04-29 Medtronic, Inc. Controlling therapy based on sleep quality
US7491181B2 (en) * 2004-03-16 2009-02-17 Medtronic, Inc. Collecting activity and sleep quality information via a medical device
US7330760B2 (en) * 2004-03-16 2008-02-12 Medtronic, Inc. Collecting posture information to evaluate therapy
US7792583B2 (en) 2004-03-16 2010-09-07 Medtronic, Inc. Collecting posture information to evaluate therapy
US7717848B2 (en) * 2004-03-16 2010-05-18 Medtronic, Inc. Collecting sleep quality information via a medical device
US7881798B2 (en) 2004-03-16 2011-02-01 Medtronic Inc. Controlling therapy based on sleep quality
US7313440B2 (en) * 2004-04-14 2007-12-25 Medtronic, Inc. Collecting posture and activity information to evaluate therapy
US8135473B2 (en) 2004-04-14 2012-03-13 Medtronic, Inc. Collecting posture and activity information to evaluate therapy
US7031766B1 (en) 2004-04-20 2006-04-18 Pacesetter, Inc. Methods and devices for determining exercise diagnostic parameters
US7676262B1 (en) 2004-04-20 2010-03-09 Pacesetter, Inc. Methods and devices for determining exercise compliance diagnostics
US7043294B1 (en) 2004-04-20 2006-05-09 Pacesetter, Inc. Methods and devices for determining heart rate recovery
US7171271B2 (en) * 2004-05-11 2007-01-30 Pacesetter, Inc. System and method for evaluating heart failure using an implantable medical device based on heart rate during patient activity
US7548785B2 (en) * 2004-06-10 2009-06-16 Pacesetter, Inc. Collecting and analyzing sensed information as a trend of heart failure progression or regression
US7559901B2 (en) * 2004-07-28 2009-07-14 Cardiac Pacemakers, Inc. Determining a patient's posture from mechanical vibrations of the heart
US7269458B2 (en) 2004-08-09 2007-09-11 Cardiac Pacemakers, Inc. Cardiopulmonary functional status assessment via heart rate response detection by implantable cardiac device
US7389143B2 (en) * 2004-08-12 2008-06-17 Cardiac Pacemakers, Inc. Cardiopulmonary functional status assessment via metabolic response detection by implantable cardiac device
AU2005304912A1 (en) * 2004-11-04 2006-05-18 Smith & Nephew, Inc. Cycle and load measurement device
US7373820B1 (en) 2004-11-23 2008-05-20 James Terry L Accelerometer for data collection and communication
US7662104B2 (en) 2005-01-18 2010-02-16 Cardiac Pacemakers, Inc. Method for correction of posture dependence on heart sounds
US7386345B2 (en) * 2005-01-27 2008-06-10 Cardiac Pacemakers, Inc. Apparatus and method for temporary treatment of acute heart failure decompensation
US7708693B2 (en) * 2005-01-27 2010-05-04 Medtronic, Inc. System and method for detecting artifactual hemodynamic waveform data
US7367951B2 (en) * 2005-01-27 2008-05-06 Medtronic, Inc. System and method for detecting cardiovascular health conditions using hemodynamic pressure waveforms
US7680534B2 (en) * 2005-02-28 2010-03-16 Cardiac Pacemakers, Inc. Implantable cardiac device with dyspnea measurement
US7526335B2 (en) * 2005-03-10 2009-04-28 Medtronic, Inc. Communications system for an implantable device and a drug dispenser
US7392086B2 (en) 2005-04-26 2008-06-24 Cardiac Pacemakers, Inc. Implantable cardiac device and method for reduced phrenic nerve stimulation
US7499751B2 (en) * 2005-04-28 2009-03-03 Cardiac Pacemakers, Inc. Cardiac signal template generation using waveform clustering
WO2006119186A2 (en) * 2005-05-02 2006-11-09 University Of Virginia Patent Foundation Systems, devices, and methods for interpreting movement
US7404802B2 (en) * 2005-05-05 2008-07-29 Cardiac Pacemakers, Inc. Trending of systolic murmur intensity for monitoring cardiac disease with implantable device
US7670298B2 (en) * 2005-06-01 2010-03-02 Cardiac Pacemakers, Inc. Sensing rate of change of pressure in the left ventricle with an implanted device
US8021299B2 (en) * 2005-06-01 2011-09-20 Medtronic, Inc. Correlating a non-polysomnographic physiological parameter set with sleep states
US8972002B2 (en) 2005-06-01 2015-03-03 Cardiac Pacemakers, Inc. Remote closed-loop titration of decongestive therapy for the treatment of advanced heart failure
US7922669B2 (en) 2005-06-08 2011-04-12 Cardiac Pacemakers, Inc. Ischemia detection using a heart sound sensor
US20070021678A1 (en) * 2005-07-19 2007-01-25 Cardiac Pacemakers, Inc. Methods and apparatus for monitoring physiological responses to steady state activity
US7585279B2 (en) 2005-07-26 2009-09-08 Cardiac Pacemakers, Inc. Managing preload reserve by tracking the ventricular operating point with heart sounds
US7634309B2 (en) * 2005-08-19 2009-12-15 Cardiac Pacemakers, Inc. Tracking progression of congestive heart failure via a force-frequency relationship
US20070073590A1 (en) * 2005-08-22 2007-03-29 Cosentino Louis C Remote monitor for physiological parameters and durable medical supplies
WO2007025191A1 (en) 2005-08-23 2007-03-01 Smith & Nephew, Inc. Telemetric orthopaedic implant
US20070055115A1 (en) * 2005-09-08 2007-03-08 Jonathan Kwok Characterization of sleep disorders using composite patient data
US9168383B2 (en) 2005-10-14 2015-10-27 Pacesetter, Inc. Leadless cardiac pacemaker with conducted communication
US9358400B2 (en) 2005-10-14 2016-06-07 Pacesetter, Inc. Leadless cardiac pacemaker
AT502921B1 (en) * 2005-10-21 2012-01-15 Falko Dr Skrabal DEVICE FOR MEASURING HEART AND VESSEL FUNCTION (FUNCTION) AND BODY SPACES (SPACES) BY MEANS OF IMPEDANCE MEASUREMENT
US7574255B1 (en) * 2005-11-07 2009-08-11 Pacesetter, Inc. Criteria for monitoring intrathoracic impedance
US7774055B1 (en) 2005-11-07 2010-08-10 Pacesetter, Inc. Left atrial pressure-based criteria for monitoring intrathoracic impedance
US8108034B2 (en) 2005-11-28 2012-01-31 Cardiac Pacemakers, Inc. Systems and methods for valvular regurgitation detection
US8016776B2 (en) * 2005-12-02 2011-09-13 Medtronic, Inc. Wearable ambulatory data recorder
US7957809B2 (en) 2005-12-02 2011-06-07 Medtronic, Inc. Closed-loop therapy adjustment
US7785256B1 (en) 2006-01-11 2010-08-31 Pacesetter, Inc. Method and system for displaying patient activity data using Poincaré and intensity plot
US7925344B2 (en) * 2006-01-20 2011-04-12 Medtronic, Inc. System and method of using AV conduction timing
US7671733B2 (en) * 2006-03-17 2010-03-02 Koninklijke Philips Electronics N.V. Method and system for medical alarm monitoring, reporting and normalization
US8744587B2 (en) 2006-03-24 2014-06-03 Medtronic, Inc. Collecting gait information for evaluation and control of therapy
US7780606B2 (en) * 2006-03-29 2010-08-24 Cardiac Pacemakers, Inc. Hemodynamic stability assessment based on heart sounds
US7613672B2 (en) 2006-04-27 2009-11-03 Cardiac Pacemakers, Inc. Medical device user interface automatically resolving interaction between programmable parameters
EP2036364A4 (en) * 2006-05-17 2013-02-06 24Eight Llc Method and apparatus for mobility analysis using real-time acceleration data
US8294716B2 (en) * 2006-05-31 2012-10-23 Koninklijke Philips Electronics N.V. Display of trends and anticipated trends from mitigation
US8000780B2 (en) 2006-06-27 2011-08-16 Cardiac Pacemakers, Inc. Detection of myocardial ischemia from the time sequence of implanted sensor measurements
US20080071185A1 (en) * 2006-08-08 2008-03-20 Cardiac Pacemakers, Inc. Periodic breathing during activity
US8226570B2 (en) 2006-08-08 2012-07-24 Cardiac Pacemakers, Inc. Respiration monitoring for heart failure using implantable device
US8209013B2 (en) 2006-09-14 2012-06-26 Cardiac Pacemakers, Inc. Therapeutic electrical stimulation that avoids undesirable activation
US20080119749A1 (en) * 2006-11-20 2008-05-22 Cardiac Pacemakers, Inc. Respiration-synchronized heart sound trending
US8096954B2 (en) * 2006-11-29 2012-01-17 Cardiac Pacemakers, Inc. Adaptive sampling of heart sounds
US20080161651A1 (en) * 2006-12-27 2008-07-03 Cardiac Pacemakers, Inc. Surrogate measure of patient compliance
US7736319B2 (en) * 2007-01-19 2010-06-15 Cardiac Pacemakers, Inc. Ischemia detection using heart sound timing
US8014863B2 (en) * 2007-01-19 2011-09-06 Cardiac Pacemakers, Inc. Heart attack or ischemia detector
WO2008103181A1 (en) 2007-02-23 2008-08-28 Smith & Nephew, Inc. Processing sensed accelerometer data for determination of bone healing
US8068918B2 (en) * 2007-03-09 2011-11-29 Enteromedics Inc. Remote monitoring and control of implantable devices
US20080228093A1 (en) * 2007-03-13 2008-09-18 Yanting Dong Systems and methods for enhancing cardiac signal features used in morphology discrimination
US7844336B2 (en) 2007-04-10 2010-11-30 Cardiac Pacemakers, Inc. Implantable medical device configured as a pedometer
US7853327B2 (en) 2007-04-17 2010-12-14 Cardiac Pacemakers, Inc. Heart sound tracking system and method
US8831714B2 (en) * 2007-05-07 2014-09-09 Cardiac Pacemakers, Inc. Apparatus and method for heart failure indication based on heart rate, onset and tachyarrhythmia
US20080281165A1 (en) * 2007-05-09 2008-11-13 Raghu Rai system and method for acquiring and transferring data to a remote server
US20080300657A1 (en) * 2007-05-31 2008-12-04 Mark Raymond Stultz Therapy system
US20080306762A1 (en) * 2007-06-08 2008-12-11 James Terry L System and Method for Managing Absenteeism in an Employee Environment
US9743859B2 (en) 2007-06-15 2017-08-29 Cardiac Pacemakers, Inc. Daytime/nighttime respiration rate monitoring
US7530956B2 (en) 2007-06-15 2009-05-12 Cardiac Pacemakers, Inc. Daytime/nighttime respiration rate monitoring
US20090018404A1 (en) * 2007-07-12 2009-01-15 Cardiac Pacemakers, Inc. Cardiovascular Autonomic Neuropathy Testing Utilizing an Implantable Medical Device
DE102007034042A1 (en) * 2007-07-20 2009-01-22 Biotronik Crm Patent Ag Implantable medical device
US8043215B2 (en) * 2007-08-07 2011-10-25 Cardiac Pacemakers, Inc. Drug titration utilizing an implantable medical device
US8265736B2 (en) * 2007-08-07 2012-09-11 Cardiac Pacemakers, Inc. Method and apparatus to perform electrode combination selection
US9037239B2 (en) 2007-08-07 2015-05-19 Cardiac Pacemakers, Inc. Method and apparatus to perform electrode combination selection
US20090048493A1 (en) * 2007-08-17 2009-02-19 James Terry L Health and Entertainment Device for Collecting, Converting, Displaying and Communicating Data
EP2191534B1 (en) 2007-09-06 2016-10-26 Smith & Nephew, Inc. System and method for communicating with a telemetric implant
US9254100B2 (en) * 2007-09-12 2016-02-09 Cardiac Pacemakers, Inc. Logging daily average metabolic activity using a motion sensor
US8897868B2 (en) 2007-09-14 2014-11-25 Medtronic, Inc. Medical device automatic start-up upon contact to patient tissue
US8591430B2 (en) 2007-09-14 2013-11-26 Corventis, Inc. Adherent device for respiratory monitoring
EP2200499B1 (en) 2007-09-14 2019-05-01 Medtronic Monitoring, Inc. Multi-sensor patient monitor to detect impending cardiac decompensation
US8116841B2 (en) 2007-09-14 2012-02-14 Corventis, Inc. Adherent device with multiple physiological sensors
US8460189B2 (en) 2007-09-14 2013-06-11 Corventis, Inc. Adherent cardiac monitor with advanced sensing capabilities
WO2009036333A1 (en) 2007-09-14 2009-03-19 Corventis, Inc. Dynamic pairing of patients to data collection gateways
US8684925B2 (en) 2007-09-14 2014-04-01 Corventis, Inc. Injectable device for physiological monitoring
US8121689B2 (en) 2007-10-01 2012-02-21 Cardiac Pacemakers, Inc. Proactive interactive limits override for implantable medical device user interface
JP2011501276A (en) * 2007-10-12 2011-01-06 ペイシェンツライクミー, インコーポレイテッド Self-improvement methods using online communities to predict health-related outcomes
US7676332B2 (en) * 2007-12-27 2010-03-09 Kersh Risk Management, Inc. System and method for processing raw activity energy expenditure data
US9020780B2 (en) * 2007-12-31 2015-04-28 The Nielsen Company (Us), Llc Motion detector module
US8915866B2 (en) * 2008-01-18 2014-12-23 Warsaw Orthopedic, Inc. Implantable sensor and associated methods
US8986253B2 (en) 2008-01-25 2015-03-24 Tandem Diabetes Care, Inc. Two chamber pumps and related methods
US20110004076A1 (en) * 2008-02-01 2011-01-06 Smith & Nephew, Inc. System and method for communicating with an implant
US20090204422A1 (en) * 2008-02-12 2009-08-13 James Terry L System and Method for Remotely Updating a Health Station
CN101939051B (en) 2008-02-14 2013-07-10 心脏起搏器公司 Method and apparatus for phrenic stimulation detection
WO2009110996A1 (en) * 2008-03-05 2009-09-11 Cardiac Pacemakers, Inc. Automated heart function classification to standardized classes
WO2009114548A1 (en) 2008-03-12 2009-09-17 Corventis, Inc. Heart failure decompensation prediction based on cardiac rhythm
EP2252209B1 (en) * 2008-03-14 2012-01-18 Koninklijke Philips Electronics N.V. An activity monitoring system insensitive to accelerations induced by external motion factors
US8412317B2 (en) 2008-04-18 2013-04-02 Corventis, Inc. Method and apparatus to measure bioelectric impedance of patient tissue
US9320448B2 (en) 2008-04-18 2016-04-26 Pacesetter, Inc. Systems and methods for improved atrial fibrillation (AF) monitoring
US8165840B2 (en) 2008-06-12 2012-04-24 Cardiac Pacemakers, Inc. Posture sensor automatic calibration
US9050471B2 (en) 2008-07-11 2015-06-09 Medtronic, Inc. Posture state display on medical device user interface
US8958885B2 (en) * 2008-07-11 2015-02-17 Medtronic, Inc. Posture state classification for a medical device
US9440084B2 (en) * 2008-07-11 2016-09-13 Medtronic, Inc. Programming posture responsive therapy
US8231556B2 (en) * 2008-07-11 2012-07-31 Medtronic, Inc. Obtaining baseline patient information
US8437861B2 (en) * 2008-07-11 2013-05-07 Medtronic, Inc. Posture state redefinition based on posture data and therapy adjustments
US8708934B2 (en) * 2008-07-11 2014-04-29 Medtronic, Inc. Reorientation of patient posture states for posture-responsive therapy
US8200340B2 (en) * 2008-07-11 2012-06-12 Medtronic, Inc. Guided programming for posture-state responsive therapy
US8504150B2 (en) 2008-07-11 2013-08-06 Medtronic, Inc. Associating therapy adjustments with posture states using a stability timer
US8447411B2 (en) 2008-07-11 2013-05-21 Medtronic, Inc. Patient interaction with posture-responsive therapy
US20100016742A1 (en) * 2008-07-19 2010-01-21 James Terry L System and Method for Monitoring, Measuring, and Addressing Stress
WO2010011678A1 (en) * 2008-07-21 2010-01-28 Seattle Information Systems, Inc. Person reported outcome report generation
US8712509B2 (en) * 2008-07-25 2014-04-29 Medtronic, Inc. Virtual physician acute myocardial infarction detection system and method
US9713701B2 (en) 2008-07-31 2017-07-25 Medtronic, Inc. Using multiple diagnostic parameters for predicting heart failure events
US8255046B2 (en) * 2008-07-31 2012-08-28 Medtronic, Inc. Detecting worsening heart failure based on impedance measurements
US8280517B2 (en) 2008-09-19 2012-10-02 Medtronic, Inc. Automatic validation techniques for validating operation of medical devices
AU2009293019A1 (en) 2008-09-19 2010-03-25 Tandem Diabetes Care Inc. Solute concentration measurement device and related methods
US8632473B2 (en) * 2009-01-30 2014-01-21 Medtronic, Inc. Detecting worsening heart failure based on fluid accumulation with respiratory confirmation
US8527068B2 (en) 2009-02-02 2013-09-03 Nanostim, Inc. Leadless cardiac pacemaker with secondary fixation capability
US8152694B2 (en) * 2009-03-16 2012-04-10 Robert Bosch Gmbh Activity monitoring device and method
US8326426B2 (en) * 2009-04-03 2012-12-04 Enteromedics, Inc. Implantable device with heat storage
US9026223B2 (en) 2009-04-30 2015-05-05 Medtronic, Inc. Therapy system including multiple posture sensors
US8175720B2 (en) 2009-04-30 2012-05-08 Medtronic, Inc. Posture-responsive therapy control based on patient input
EP2430574A1 (en) 2009-04-30 2012-03-21 Patientslikeme, Inc. Systems and methods for encouragement of data submission in online communities
US9327070B2 (en) * 2009-04-30 2016-05-03 Medtronic, Inc. Medical device therapy based on posture and timing
JP2012525952A (en) * 2009-06-03 2012-10-25 カーディアック ペースメイカーズ, インコーポレイテッド System and method for monitoring cardiovascular pressure
BRPI1016004A2 (en) * 2009-06-30 2016-04-26 Lifescan Inc methods for testing analytes and device for calculating basal insulin therapy.
EP2455875A3 (en) * 2009-06-30 2013-01-16 Lifescan Scotland Limited System and method for diabetes management
EP3284494A1 (en) 2009-07-30 2018-02-21 Tandem Diabetes Care, Inc. Portable infusion pump system
BR112012007134A2 (en) * 2009-09-29 2016-08-23 Lifescan Scotland Ltd diabetes control analyte test device and method
WO2011050283A2 (en) 2009-10-22 2011-04-28 Corventis, Inc. Remote detection and monitoring of functional chronotropic incompetence
US20110106201A1 (en) * 2009-10-30 2011-05-05 Sourav Bhunia Implantable heart failure monitor
US8271072B2 (en) * 2009-10-30 2012-09-18 Medtronic, Inc. Detecting worsening heart failure
US9451897B2 (en) 2009-12-14 2016-09-27 Medtronic Monitoring, Inc. Body adherent patch with electronics for physiologic monitoring
US8758274B2 (en) * 2010-01-08 2014-06-24 Medtronic, Inc. Automated adjustment of posture state definitions for a medical device
US9956418B2 (en) 2010-01-08 2018-05-01 Medtronic, Inc. Graphical manipulation of posture zones for posture-responsive therapy
US9357949B2 (en) 2010-01-08 2016-06-07 Medtronic, Inc. User interface that displays medical therapy and posture data
US8579834B2 (en) * 2010-01-08 2013-11-12 Medtronic, Inc. Display of detected patient posture state
US8257289B2 (en) * 2010-02-03 2012-09-04 Tyco Healthcare Group Lp Fitting of compression garment
JP5588020B2 (en) * 2010-02-16 2014-09-10 カーディアック ペースメイカーズ, インコーポレイテッド Dynamics of physiological responses to movements in daily life movements
EP2590098B1 (en) * 2010-02-25 2014-11-05 Lifescan Scotland Limited Analyte testing method and system with high and low blood glucose trends notification
US8965498B2 (en) 2010-04-05 2015-02-24 Corventis, Inc. Method and apparatus for personalized physiologic parameters
US9566441B2 (en) 2010-04-30 2017-02-14 Medtronic, Inc. Detecting posture sensor signal shift or drift in medical devices
US20120083712A1 (en) 2010-09-30 2012-04-05 Tyco Healthcare Group Lp Monitoring Compliance Using Venous Refill Detection
EP2627403A4 (en) 2010-10-12 2014-03-26 Nanostim Inc Temperature sensor for a leadless cardiac pacemaker
US9060692B2 (en) 2010-10-12 2015-06-23 Pacesetter, Inc. Temperature sensor for a leadless cardiac pacemaker
JP2013540022A (en) 2010-10-13 2013-10-31 ナノスティム・インコーポレイテッド Leadless cardiac pacemaker with screw anti-rotation element
US8585604B2 (en) 2010-10-29 2013-11-19 Medtronic, Inc. Integrated patient care
JP2014501136A (en) 2010-12-13 2014-01-20 ナノスティム・インコーポレイテッド Delivery catheter system and method
WO2012082755A1 (en) 2010-12-13 2012-06-21 Nanostim, Inc. Pacemaker retrieval systems and methods
EP2654889B1 (en) 2010-12-20 2017-03-01 Pacesetter, Inc. Leadless pacemaker with radial fixation mechanism
US10098584B2 (en) 2011-02-08 2018-10-16 Cardiac Pacemakers, Inc. Patient health improvement monitor
US9069380B2 (en) 2011-06-10 2015-06-30 Aliphcom Media device, application, and content management using sensory input
US8818505B2 (en) 2011-09-28 2014-08-26 Medtronic, Inc. Physiological perturbations for measuring heart failure
WO2013067496A2 (en) 2011-11-04 2013-05-10 Nanostim, Inc. Leadless cardiac pacemaker with integral battery and redundant welds
US9907959B2 (en) 2012-04-12 2018-03-06 Medtronic, Inc. Velocity detection for posture-responsive therapy
US9737719B2 (en) 2012-04-26 2017-08-22 Medtronic, Inc. Adjustment of therapy based on acceleration
US9180242B2 (en) 2012-05-17 2015-11-10 Tandem Diabetes Care, Inc. Methods and devices for multiple fluid transfer
US9555186B2 (en) 2012-06-05 2017-01-31 Tandem Diabetes Care, Inc. Infusion pump system with disposable cartridge having pressure venting and pressure feedback
EP2879758B1 (en) 2012-08-01 2018-04-18 Pacesetter, Inc. Biostimulator circuit with flying cell
US8761717B1 (en) 2012-08-07 2014-06-24 Brian K. Buchheit Safety feature to disable an electronic device when a wireless implantable medical device (IMD) is proximate
US9395234B2 (en) 2012-12-05 2016-07-19 Cardiocom, Llc Stabilizing base for scale
US9173998B2 (en) 2013-03-14 2015-11-03 Tandem Diabetes Care, Inc. System and method for detecting occlusions in an infusion pump
FR3006575B1 (en) * 2013-06-05 2018-02-02 L.3 Medical DEVICE FOR REMOTELY TRACKING AT LEAST ONE MEDICAL DEVICE
US9830424B2 (en) 2013-09-18 2017-11-28 Hill-Rom Services, Inc. Bed/room/patient association systems and methods
US20150277397A1 (en) * 2014-03-31 2015-10-01 Elwha LLC, a limited liability company of the State of Delaware Quantified-Self Machines and Circuits Reflexively Related to Food Fabricator Machines and Circuits
US10318123B2 (en) 2014-03-31 2019-06-11 Elwha Llc Quantified-self machines, circuits and interfaces reflexively related to food fabricator machines and circuits
US9922307B2 (en) 2014-03-31 2018-03-20 Elwha Llc Quantified-self machines, circuits and interfaces reflexively related to food
US10127361B2 (en) 2014-03-31 2018-11-13 Elwha Llc Quantified-self machines and circuits reflexively related to kiosk systems and associated food-and-nutrition machines and circuits
US10058708B2 (en) 2015-06-30 2018-08-28 Cardiac Pacemakers, Inc. Heart failure event detection using minimum heart rate
CN108697571B (en) 2015-10-09 2021-07-13 Kpr美国有限责任公司 Compression garment compliance
US10610132B2 (en) 2016-08-02 2020-04-07 Medtronic, Inc. Step detection using accelerometer axis
US10952686B2 (en) 2016-08-02 2021-03-23 Medtronic, Inc. Mobile application to prompt physical action to measure physiologic response in implantable device
CN106551691B (en) * 2016-12-02 2020-01-21 清华大学 Heart rate variability analysis method, device and application
US11596795B2 (en) 2017-07-31 2023-03-07 Medtronic, Inc. Therapeutic electrical stimulation therapy for patient gait freeze
US11894139B1 (en) 2018-12-03 2024-02-06 Patientslikeme Llc Disease spectrum classification
US11911325B2 (en) 2019-02-26 2024-02-27 Hill-Rom Services, Inc. Bed interface for manual location
US10504496B1 (en) 2019-04-23 2019-12-10 Sensoplex, Inc. Music tempo adjustment apparatus and method based on gait analysis
US11642035B2 (en) 2019-06-28 2023-05-09 Medtronic, Inc. Heart rate recovery assessment
US11717186B2 (en) 2019-08-27 2023-08-08 Medtronic, Inc. Body stability measurement
US11602313B2 (en) 2020-07-28 2023-03-14 Medtronic, Inc. Determining a fall risk responsive to detecting body position movements
US20220071513A1 (en) * 2020-09-08 2022-03-10 Medtronic, Inc. Detection of changes in patient health based on peak and non-peak patient activity data

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4086916A (en) 1975-09-19 1978-05-02 Joseph J. Cayre Cardiac monitor wristwatch
US4112936A (en) * 1976-09-27 1978-09-12 Blachly Paul H Bite block assembly adapted for adjustable mounting and holding of oral airways and method of using same
US4353375A (en) * 1977-04-26 1982-10-12 The United States Of America As Represented By The Department Of Health & Human Services Activity monitor for ambulatory subjects
US4731051A (en) * 1979-04-27 1988-03-15 The Johns Hopkins University Programmable control means for providing safe and controlled medication infusion
US4275727A (en) * 1980-01-07 1981-06-30 Keeri Szanto Michael Device for monitoring and controlling self-administered intravenous drug dosage
US5101814A (en) * 1989-08-11 1992-04-07 Palti Yoram Prof System for monitoring and controlling blood glucose
US5012814A (en) 1989-11-09 1991-05-07 Instromedix, Inc. Implantable-defibrillator pulse detection-triggered ECG monitoring method and apparatus
US5086772A (en) 1990-07-30 1992-02-11 Telectronics Pacing Systems, Inc. Arrhythmia control system employing arrhythmia recognition algorithm
US5113869A (en) 1990-08-21 1992-05-19 Telectronics Pacing Systems, Inc. Implantable ambulatory electrocardiogram monitor
US5293879A (en) * 1991-09-23 1994-03-15 Vitatron Medical, B.V. System an method for detecting tremors such as those which result from parkinson's disease
US5313953A (en) 1992-01-14 1994-05-24 Incontrol, Inc. Implantable cardiac patient monitor
US5312446A (en) * 1992-08-26 1994-05-17 Medtronic, Inc. Compressed storage of data in cardiac pacemakers
US5404877A (en) 1993-06-04 1995-04-11 Telectronics Pacing Systems, Inc. Leadless implantable sensor assembly and a cardiac emergency warning alarm
US5404887A (en) 1993-11-04 1995-04-11 Scimed Life Systems, Inc. Guide wire having an unsmooth exterior surface
US5411031A (en) 1993-11-24 1995-05-02 Incontrol, Inc. Implantable cardiac patient monitor
US5520637A (en) * 1995-01-31 1996-05-28 Pager; David Closed-loop system for infusing oxytocin
SE9504707L (en) * 1995-12-29 1997-06-30 Alfa Laval Agri Ab activity Measurement

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