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Número de publicaciónUSRE38119 E1
Tipo de publicaciónConcesión
Número de solicitudUS 08/547,691
Fecha de publicación20 May 2003
Fecha de presentación19 Oct 1995
Fecha de prioridad23 Ene 1989
También publicado comoUSRE39897
Número de publicación08547691, 547691, US RE38119 E1, US RE38119E1, US-E1-RE38119, USRE38119 E1, USRE38119E1
InventoresMorton M. Mower
Cesionario originalMirowski Family Ventures, LLC
Exportar citaBiBTeX, EndNote, RefMan
Enlaces externos: USPTO, Cesión de USPTO, Espacenet
Method and apparatus for treating hemodynamic disfunction
US RE38119 E1
Resumen
A method of treating hemodynamic disfunction by simultaneously pacing both ventricles of a heart. At least one ECG amplifier is arranged to separately detect contraction of each ventricle and a stimulator is then activated for issuing stimulating pulses to both ventricles in a manner to assure simultaneous contraction of both ventricles, thereby to assure hemodynamic efficiency. A first ventricle is stimulated simultaneously with contraction of a second ventricle when the first fails to properly contract. Further, both ventricles are stimulated after lapse of a predetermined A-V escape interval. One of a pair of electrodes, connected in series, is placed through the superior vena cava into the right ventricle and a second is placed in the coronary sinus about the left ventricle. Each electrode performs both pacing and sensing functions. The pacer is particularly suitable for treating bundle branch blocks or slow conduction in a portion of the ventricles.
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Reclamaciones(26)
What is claimed is:
1. A method for improving the hemodynamic efficiency of a sick heart comprising the steps of:
(a) detecting respective cardiac signals originating in the left and right ventricles of the heart;
(b) analyzing said cardiac signals and the absence thereof in an electronic control circuit; and
(c) providing electrical pulses from a stimulating circuit controlled by said control circuit to one, the other or both ventricles as required for effecting substantially simultaneous contraction of both ventricles, said step of analyzing including providing a control signal from said control circuit to said stimulating circuit for producing an electrical stimulating pulse to one or both ventricles in response to the absence of a detected cardiac signal from one or both ventricles within a time interval which is a small fraction of the pulse width of a detected cardiac signal.
2. The method of claim 1 wherein said step of detecting respective cardiac signals comprises deposing electrodes in or on the left and right ventricles for separately detecting the respective cardiac signals of the left and right ventricles, and applying said cardiac signals to separate ECG amplifier means connected to each of said electrodes to amplify the cardiac signal for analysis.
3. The method of claim 2 wherein said step of providing electrical pulses includes delivering an electrical pulse from said stimulating circuit to said electrodes in or on both the left and right ventricles.
4. The method of claim 1 wherein said step of analyzing further includes providing a control signal from said control circuit to the stimulating circuit to produce an electrical stimulating pulse to the left ventricle in the absence of a detected cardiac signal from the left ventricle, or to the right ventricle in the absence of a detected cardiac signal from the right ventricle, or to both ventricles in the absence of detected cardiac signals from both ventricles.
5. A method for effecting simultaneous contraction of both left and right ventricles of a heart for improving hemodynamic efficiency comprising the steps of:
separately sensing for the presence of cardiac depolarization signals from both left and right ventricles;
determining whether said cardiac depolarization signals are simultaneously present in both the left and right ventricles; and
stimulating at least one ventricle substantially simultaneously with the contraction of a least one other ventricle in the event that said cardiac depolarization signals are determined not to be simultaneously present in both ventricles.
6. A method of effecting simultaneous contraction of both left and right ventricles of a heart for improving hemodynamic efficiency comprising the steps of:
sensing the cardiac signals of the atria and separately sensing the cardiac depolarization signals of both the left and right ventricles;
determining whether said cardiac depolarization signals are simultaneously present in both the left and right ventricles;
stimulating at least one ventricle simultaneously with the contraction of at least one other ventricle after a predetermined A-V period in the event that said cardiac depolarization signals are determined not to be simultaneously present in both ventricles.
7. A method of increasing the cardiac output of a sick heart comprising the steps of:
(a) implanting a pacing lead having at least two sensing/pacing electrodes in the body such that one of said sensing/pacing electrodes is in or on the right ventricle and the other of said sensing/pacing electrodes is in or on the left ventricle;
(b) sensing depolarization signals picked up by said sensing/pacing electrodes upon their occurrence;
(c) determining whether the depolarization signals sensed in step (b) fail to occur within a predetermined time interval of one another and, if so;
(d) applying an electrical stimulating pulse to the sensing/pacing electrode associated with the ventricle not producing a depolarization signal within said time interval at the conclusion of said time interval.
8. The method as in claim 7 wherein said predetermined time interval is in the range of from about 5 ms. to 10 ms.
9. A bi-ventricular pacemaker, comprising:
(a) sense means for sensing ventricular depolarization signals originating in or on the right and left ventricles;
(b) means coupled to said sense means for initiating a time delay of a predetermined length which is short compared to the period of a QRS complex upon detection of a ventricular depolarization signal in one of said right or left ventricles; and
(c) pulse generator means operative upon the termination of said time delay for producing a ventricular simulating pulse and applying same to the other of said right or left ventricles unless a ventricular depolarization signal occurs in said other of said right or left ventricle prior to the expiration of said time delay.
10. The bi-ventricular pacemaker as in claim 9 wherein said sense means comprises a bi-ventricular lead having a first electrode for contacting the left ventricle and sense amplifier means electrically coupled to said first and second electrodes.
11. The bi-ventricular pacemaker as in claim 10 wherein said means coupled to said sense means includes:
(a) first and second set-reset flip-flop connected to be set by an output from said sense amplifier means;
(b) presetable counter means for initially containing a digital value representative of said time delay;
(c) means for incrementing or decrementing said digital value in said presettable couter means at regular intervals until a predetermined count is reached;
(d) means responsive to the value in said counter means reaching said predetermined count for producing a control signal;
(e) logic means coupled to said first and second flip-flops and to said presettable counter means for receiving said control signals; and wherein
(f) said pulse generator means is enabled by said logic means.
12. The bi-ventricular pacemaker as in claim 11 wherein said pulse generator means is coupled to said first and second electrodes.
13. An atrial-coupled, bi-ventricular pacemaker for implantation or external use comprising atrial and ventricular sensing means for detecting cardiac signals, said sensing means including first and second ventricular electrodes connected in series for sensing and stimulating the right and left ventricles, respectively, and an atrial electrode adapted to be disposed in an atrial chamber for detecting cardiac signals of the atria, all of said electrodes being connected to separate ECG amplifier means for amplifying the sensed signals; a control circuit coupled to said ECG amplifier means for analyzing the cardiac signals picked up by said sensing means and providing a control signal; and a stimulating circuit means for producing an electrical stimulating pulse to the left ventricle in the absence of a detected cardiac signal from the left ventricle, and to the right ventricle in the absence of a detected cardiac signal from the right ventricle, and to both ventricles in the absence of detected cardiac signals from both ventricles to effect substantially simultaneous contraction of both ventricles after a predetermined A-V delay period.
14. The pacemaker of claim 13 wherein said first electrode is adapted to be placed in the right ventricle and the second electrode is adapted to be placed in the coronary sinus extending about the left ventricle.
15. A method for improving the hemodynamic efficiency of a heart comprising the steps of:
detecting a cardiac depolarization signal originating from a first ventricle;
immediately and unconditionally stimulating both ventricles for effecting a coordinated contraction of both ventricles when a cardiac depolarization signal originating from the first ventricle is detected.
16. The method of claim 15 wherein the step of immediately and unconditionally stimulating both ventricles further comprises providing electrical pulses from a stimulating circuit to both ventricles.
17. The method of claim 16 wherein said step of detecting a cardiac depolarization signal further comprises positioning electrodes in or about both ventricles for detecting cardiac depolarization signals and for conducting a signal to an electronic control circuit for controlling the stimulating circuit.
18. The method of claim 17 wherein said step of detecting a cardiac depolarization signal further comprises conducting the signal to an amplifier means to amplify the detected signal, and applying the amplified signal to the control circuit.
19. A method for improving the hemodynamic efficiency of a heart comprising the steps of:
sensing a contraction of the atria; and
stimulating both ventricles for effecting a coordinated contraction of both ventricles when a contraction of the atria is sensed and following a predetermined A-V delay period.
20. The method according to claim 19, further comprising, before said sensing step:
placing a first electrode into the right ventricle through the superior vena cava and placing a second electrode into the left ventricle through the coronary sinus;
wherein said stimulation of both ventricles is an electrical discharge through said first and second electrode.
21. The method according to claim 19, further comprising, before said sensing step:
placing a pair of sensing and pacing tip electrodes into each of the right and left ventricles;
wherein said sensing is detected through said pair of sensing tip electrodes.
22. A bi-ventricular pacemaker, comprising:
sense means for sensing ventricular depolarization signals originating from one of left and right ventricles; and
pulse generator means operative upon sensing a depolarization signal from the one of the ventricles for producing a stimulating pulse and immediately and unconditionally applying the stimulating pulse to both ventricles.
23. A bi-ventricular pacemaker according to claim 22 , wherein the sense means includes a lead having a first electrode for placement in or about the left ventricle and a second electrode for placement in or about the right ventricle.
24. A bi-ventricular pacemaker according to claim 22 , wherein the pulse generator means includes a sense amplifier means electrically coupled to the first and second electrodes for amplifying a sensed depolarization signal, a stimulating circuit for producing the stimulating pulse, and a control circuit operative to control the stimulating circuit in response to the amplified sensed depolarization signal.
25. A bi-ventricular pacemaker comprising:
detecting means for detecting a cardiac signal resulting from a contraction of a first ventricle;
stimulating means for effecting immediate and unconditional contraction of a second ventricle in response to the detected cardiac signal, thereby effecting simultaneous contraction of both ventricles.
26. A bi-ventricular pacemaker according to claim 25 further comprising stimulating means for providing a stimulating pulse to the first ventricle simultaneous with the effecting of the immediate and unconditional contraction of the second ventricle.
Descripción

Application Ser. No. 10/214,474 filed August 8, 2002 is a continuation application of the instant reissue application, Ser. No. 08/547,691, which application is, in turn, a continuation of application Ser. No. 07/890,280, filed May 29, 1992, now abandoned, which is a Reissue of Ser. No. 07/299,895, filed Jan. 23, 1989, now U.S. Pat. No. 4,928,688.

BACKGROUND OF THE INVENTION

I. Field of the Invention

This invention pertains to medical devices, but more specifically, to a method for increasing the cardiac output of a patient suffering from congestive heart failure by stimulating the heart of the patient at multiple sites simultaneously.

II. Discussion of the Prior Art

Normally, impulses from the SA node affect contraction of the atria and then propagate to the AV node. The AV node, in turn, emits a second nerve impulse which affects contraction of the ventricles. These nerve impulses affect contraction, i.e., depolarization of the tissue of the heart, in a coordinated manner to circulate blood through the body. Cardiac pacers of the type herein described generally are useful for maintaining proper functional operation of a sick heart. Of many cardiac deficiencies which have in the past been diagnosed and treated, conduction difficulties have presented significant problems for which a pacer has been used for treatment. A particular conduction deficiency, known as AV branch block, inhibits the transfer of nerve impulses from the sinoatrial (SA) node to atrial-ventricular (AV) node. When a bundle block occurs, these nerve impulses are not properly transmitted from the SA node to the AV node and ventricles.

When this condition occurs, normal treatment is to employ a pacer which locks onto the rhythmic cycle of the atrial beating signal and supplies to the ventricles a stimulating impulse at a certain time thereafter to effect contraction of the ventricles. The time period between the occurrence of the atrial beat and the normal contraction of the ventricles is known as the A-V delay period. Generally, hemodynamic efficiency is somewhat dependent to the A-V delay period, thus the pacer must emit a stimulating pulse at a time to preserve an optimum A-V delay period.

Other forms of conduction deficiency, such as myocardial scarring and bundle branch block, cause slow conduction of nerve impulses, in which case, nerve impulses are indeed passed from the SA to the AV node, but in a time period which is slower than normal. The Q-R-S complex in this case would manifest itself in being very wide and hemodynamic efficiency also becomes lower than normal.

In each of the above-mentioned cardiac deficiencies, the heart does not contract in coordinated fashion. This uncoordinated movement increases depolarization time and reults in more inefficient pumping rather than a more coordinated and simultaneous ventricular depolarization. In essence, such conduction deficiencies result in asynchrony between the left and right ventricle.

Additionally, arrhythmias of the heart produce uncoordinated ventricular contraction that affects the hemodynamic efficiency of the heart. Specifically, the recent paper “Incomplete Filling and Incoordinate Contraction as Mechanisms of Hypotension During Ventricular Tachycardia in Man”, published in Circulation, Vol. 68, No. 5, in 1983, describes that left ventricular function is severely disturbed by the disorganization of wall motion in hearts undergoing ventricular tachycardias. Moreover, it was found that hearts with impaired functions show profound reductions in pumping ability due to incoordinate contraction of the ventricles. It appears reasonable to believe, therefore, that any abnormal functioning heart that requires pacemaking or which has QRS widening will have a better hemodynamic efficiency if both ventricles are paced to contract in coordination with each other. There have been systems developed in the past employing a plurality of electrodes attached to the heart for effecting stimulation of a plurality of regions of the heart. For example, the Funke U.S. Pat. No. 3,937,226 discloses a cardiac electrical stimulation defibrillation system including a plurality of electrode terminals connected in a spaced relation on the heart. The electrodes, which provide stimulating and sensing, are each connected to amplifiers. The amplifiers are connected to electronic control circuit means configured to cause stimulation of all of the electrode terminals simultaneously in response to a sensed depolrization signal on the heart by at least one electrode terminal. In addition, the electronic control circuit is provided with a multivibrator means to synchronize the stimulation signal with the Q-R-S complex. Although Funke does teach the concept of simultaneous stimulation of a plurality of spaced electrodes, he does not disclose its specific use as a method of improving the cardiac output of patients suffering from congestive heart failure, nor does he discuss the specific placement of the electrodes about the heart.

The Rockland et al U.S. Pat. No. 4,088,140 discloses a similar system to Funke's although a specific use as a pacemaker is stated in the patent. Rockland, et al discloses a demand anti-arrythmia pacemaker including a plurality of sensing electrodes connected to the heart to sense ventricular depolarizations. Electronic circuitry is provided having two paths of operation. A first path provides stimulation to one area of the heart if depolarization of a naturally occurring heart beat fails to occur within a first predetermined time period. In this first path, it is stated that the circuitry acts as a pacemaker in the event of skipped natural heartbeats. A second path provides stimulation to a plurality of locations on the heart if a depolarization signal is sensed on the heart with a second predetermined time period. In this second path, it is stated that the circuitry acts as a synchronous multiple electrode pacemaker or a synchronous multiple electrode defibrillator. Although, one example of an electrode placed in the intraventricular section and others in a spaced relation on the heart ventricles is given, there are no teachings of the specific placement of the electrodes on the heart nor the improvement of cardiac output from a sick heart. In addition, the electrodes perform either stimulating or sensing, not both, therefore a large number of electrodes is required in this system.

The Tacker, Jr. et al and McCorkle U.S. Pat. Nos. 4,548,203, 4,458,677 and 4,332,259, respectively, disclose the specific placement of an electrode in or around both left and right ventricles of the heart. The Tacker, Jr. et al patent discloses the placement of a catheter having one electrode in the right ventricle and another outside the heart and a third electrode placed on the left ventricle. The catheter electrodes, each being paired with the left ventricular electrode, are pulsed in sequence with a predetermined time separation resulting in uniform current density delivered to the heart. However, this pulsing scheme and configuration is disclosed for use in a ventricular defibrillation device and not for cardiac pacing to improve cardiac output wherein a more precise synchronization of stimulation signals with the Q-R-S complex is required.

The McCorkle, Jr. patents disclose the specific placement of an electrode in the right ventricle and another electrode in the coronary sinus surrounding the left ventricle for connection to a pacemaker. However, there is no specific technique disclose of providing stimulating signals to the electrodes to perform a pacemaking function.

In light of the above difficulties and shortcomings of the prior art, an objective of the present invention is to provide a cardiac pacer for increasing hemodynamic efficiency of a heart experiencing a conduction deficiency.

Another objective of the invention is to ensure a more coordinated and simultaneous ventricular depolarization of both left and right ventricles of the heart.

A yet further objective of this invention is to provide a cardiac pacer suitable for being implanted in a manner so as to impose a minimal surgical risk during implantation thereof.

A further objective of this invention is to provide a method and apparatus of separately sensing and stimulating each ventricle of the heart in order for effecting simultaneous contraction automatically of both ventricles of the heart to narrow the QRS complex of a failing heart and thereby cause an increase in blood pressure and cardiac output.

SUMMARY OF THE INVENTION

The method of the present invention involves a procedure for pacing of the heart in a particular way so as to improve its contraction pattern, and thereby augment the movement of blood through the heart. Patients suffering from severe congestive heart failure, which is found not to respond well to conventional drug therapy and to have a conduction defect in the ventricle resulting in a widen Q-R-S complex have been aided by a pacing regimen in which stimulating pulses are simultaneously applied to both ventricles by way of a demand pacemaker or asynchronous pacemaker.

It is theorized that a considerable part of the hemodynamic impairment in refractory congestive heart failure with conduction defects is due to an incoordinate contraction of the heart, so that a part of the heart muscle contracts and balloons out the part that is not contracting. When the latter area of the heart muscle does finally contract, the former has relaxed, so that a large part of the blood volume is merely shunted back and forth within the heart rather than being ejected as would happen with a more coordinate contraction pattern.

To attain the foregoing and other objectives, the present invention comprises, a bi-ventricular cardiac pacer having detecting and stimulating circuits for effecting substatially simultaneous contraction of both left and right ventricles of the heart. In the preferred embodiment, the bi-ventricular pacer comprises ECG amplifier means for separately processing sensed cardiac signals from each of the right and left ventricles. The amplified sensed signals are used to determined where possible abnormal conduction delays exist on the heart and to activate an electrical stimulator for stimulating the appropriate abnormally functioning part of the heart. More specifically, the stimulator responds to the control circuit to issue stimulating pulses simultaneously to either the left or right ventricle, as appropriate. The stimulator may be of the demand type wherein pacing pulses are only issued in the absence of a normal Q-R-S complex for on or the other of the two ventricles (e.g., occasional bundle branch block or slow conduction), or the nondemand type wherein pacing pulses are always issued (e.g., permanent bundle branch block or slow conduction).

To convey and sense signals to and from the heart, the present invention includes a pacing lead assembly comprising first and second separate electrodes. The first electrode is preferably introduced through the superior vena cava into the right ventricle and the second electrode is introduced through the coronary sinus to the left ventricle. Both lead segments include a sensing and pacing tip electrode which serves to both sense a cardiac depolarization signal or to apply a stimulating pulse from an implanted pulse generator to the ventricle.

Additionally, to preserve a predetermined A-V delay period, additional atrial sensing electrodes may be placed on or around the atrial chambers of the heart and connected to the control circuit. The control circuit responds to the sensed atrial and ventricular depolarization signals to provide simultaneous ventricular contraction signals applied to the left and right ventricles following a preset A-V delay period.

The advantages of the present invention include a more precise and coordinated simultaneous ventricular depolarization of both the right and left ventricular to thereby increase hemodynamic efficiency of a patient experiencing congestive heart failure or weak contractions.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawing forming a part hereof, wherein like numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 depicts a functional block diagram of an apparatus for carrying out the teaching of this invention; and

FIG. 2 is a logic diagram of the “CONTROL” shown in FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates the overall pacing system which may be employed for carrying out the teachings of the invention. A pair of leads 12 and 14 with corresponding sensing/stimulating tip electrodes 13 and 15 are electrically connected, via conductors 18 and 21, to separate ECG sense amplifiers 16 and 17 (or to a single multiplexed amplifier). The amplifiers 16 and 17 are both connected to a control circuit unit 20. A stimulator circuit 22 is connected to the control unit 20 and has two output conductor lines 24 and 26 which are electrically connected to the conductors 18 and 21, respectively. From this structure, signals my be separately sensed by the electrodes 13 and 15 and stimulating pacing signals may be separately delivered to the electrodes 13 and 15, via lead branches 12 and 14.

In operation, the electrodes 13 and 15 are disposed in or about the right and left ventricles, respectively. A preferred surgical procedure for implanting the lead 12 is to extend it through the superior vena cava 28 so that the sensing stimulating tip 13 thereof lodges in the internal chamber of the right ventricle of the heart 10. A preferred surgical procedure for implanting lead branch 14 is to extend it through the coronary sinus (not shown) of the heart 10 so that the sensing/stimulating tip 15 thereof lodges directly in or about the coronary simus and left ventricle. Although it is described that electrodes 13 and 15 perform both sensing and pacing, it is possible for testing and examination, that separate unipolar or bipolar sensing and stimulating electrodes may be used.

When attached to the heart, the electrodes 13 and 15 sense cardiac signals in the form of well-known Q-R-S complex at separate sites with the left and right ventricles. The ECG amplifiers 16 and 17 feed the amplified versions of these signals to the control circuit 20.

The control circuit 20 analyzes the cardiac signals to determine whether an abnormal conduction exists. Specifically, if a cardiac signal is received from the left ventricle but not from the right ventricle, the control circuit 20 provides a control signal to the stimulator 22 to issue a stimulating pacing pulse over conductors 24 and 18 and lead branch 12 to the right ventricle, via the sensing/stimulating tip electrodes 13. Similarly, the control circuit 20 provides a control signal to the stimulator 22 to issue a stimulating pacing pulse over lead branch 14 to the left ventricle, via sensing/stimulating tip electrode 15, if a cardiac depolarization signal is received from the right ventricle, but not from the left ventricle. It is also possible to sense a depolarization signal from only one ventricular chamber and then unconditionally stimulate both ventricular chambers. This is wasteful of powe which is a concern only if the stimulator is totally implanted and must rely on an implanted battery power source.

The timing of the stimulating pacing pulse from the stimulator 22 is such that both ventricles will contract substantially simultaneously. Where both ventricles are unconditionally stimulated upon the occurrence of a QRS complex on only one side, the fact that ventricular site which had produced a Q-R-S complex is immediately stimulated along with the other ventricle does not cause a problem since the site producing that complex is still refractory at the time it is stimulated.

It is also possible that no cardiac signals are sensed from either ventricle, possibly resulting from complete conduction failure between the sinoatrial node and the atrialventricular node. In this case, the control circuit 20 will again activate the stimulator 22 to provide stimulating signals to both ventricles simultaneously.

In an alternative embodiment of this invention, the issuance of pacing pulses to the ventricles is time-coupled to the rhythmic cycle of the atrial beat of the heart to preserve a preset atrial-ventricular delay period of about 120 to 200 milliseconds. Additional atrial sensing is accomplished, via lead 23 and a sense electrode 25 similar to the ventricular leads 12 and 14, but disposed in or about the right atrial chamber and connected to the control circuit 20, via atrial sense amplifier 27. The control circuit 20 may be configured to respond to the sensed atrial and ventricular signals to activate the stimulator for providing appropriate simultaneous stimulating signals to the ventricles as described above in accordance with the predetermined A-V delay period.

In the case where the conduction of the natural stimulating signal originating at the sinoatrial node of the heart 10 is only partially blocked or slowed, the ventricles may partially or incompletely contract, in which case hemodynanmic efficiency is reduced. Under these circumstances, provision is made in the control circuit 20 for determining whether a Q-R-S cardiac signal, although present, is weak or slow, and if so, to activate the stimulator 22 to stimulate the ventricles of the heart by passing pacing pulses simultaneously thereto.

FIG. 2 shows one embodiment of the control circuitry 20 of FIG. 1 required to perform bi-ventricular pacing. Also shown in the circuit of FIG. 2 are means for interconnecting the bi-ventricular control circuitry with conventional demand pacing circuitry to implement various additional pacing modes. It is understood that in the preferred embodiment, the circuitry shown in FIG. 1 would be preferably incorporated directly into the design of a pacer rather than its adjunctive form shown here for purposes of illustration.

To accomplish bi-ventricular pacing, activity is sensed in both the left and the right ventricle. When a ventricular contraction is sensed in either ventricle, a timer is initiated. If within a time window established by said timer, the contraction is sensed in the other ventricle, all pacing is inhibited because the natural contractions are deemed to be simultaneous. On the other hand, if ventricular contractions are not sensed in both ventricles within a period of coincidence defined by the time delay, at the end of this delay, the pacing pulse will be emitted, but only to the ventricle for which a QRS complex has not been sensed. Generally, ventricular contractions which occur with 5-10 milliseconds of each other result in sufficient hemodynamic efficiency so as to not require treatment. Hence, the delay window may be of this order of magnitude. As used herein, the term “substantially simultaneous contraction” includes the occurence of natural contractions of both ventricles with the window period or an evoked contraction of one or both ventricles immediately following the expiration of the window period.

Operation of the circuit of FIG. 2 will now be described. Electrical activity originating in the left ventricle is sensed by electrode 15 on lead 14 coupled to amplifier 16. It is assumed that amplifier 16 contains all of the thresholding and inhibiting provisions commonly utilized in existing pacing systems to inhibit all electrical activity, save valid ventricular contractions. Similarly, electrical activity in the right ventricle is sensed by electrode 13 on lead 12 and processed by ECG amplifier 17.

Let if first be assumed that a left ventricle contraction procedes that of the right. In this case, an R-wave signal propagates through amplifier 16 to set the Set-Reset type flip-flop 30. a logical “l” signal passes through OR gate 32 to clock D-type of flop 34 to the “set” state which, in turn, initiates the aforementioned delay timing. Window register 36 is loaded with a digital count value which is representative of the desired delay window, e.g., 5-10 ms. This may be either a fixed, hard-wired register or, alternatively, a programmable register which may be set by telemetry means in a known manner. When the preset enable input (PE) in high, counter 38 is held at a digital count corresponding to the value held in window register 36. When flip-flop 34 is set, the PE on counter 38 is removed, allowing the counter to be decremented with each clock pulse provided on clock line 40. At the end of the preporgrammed window delay interval, counter 38 is decremented to zero, causing the zero detect (ZD) line 42 to go high. The leading edge of the zero detect pulse is used to trigger a ventricle pacing pulse from pulse generator 44, via gates 54 and 56, as required. The pulse generator circuitry 44 converts the leading edge trigger to a pulse of the proper amplitube and duration for effective stimulation of the right ventricle. Note that, since under the assumed conditions flip-flop 30 has been set, AND gate 48 is disabled and, therefore, pulse generator 50 is inhibited from generating a left ventricle pacing pulse.

Next to be considered is the case where a right ventricle contraction has not been sensed within the prescribed window interval. In this case, flip-flop 52 remains reset and AND gate 54 is enabled which allows the zero detect pulse ZD to propagate through OR gate 56 to trigger pulse generator 44, thus stimulating the right ventricle. If, however, a right ventricle contraction has been detected, flip-flop 52 would have been set prior to the generation of the ZD pulse and, in this case, both AND gates 48 and 54 are disabled and no pacing pulse in either ventricle is generated.

It can be seen from the symmetry of the circuit that the operation is identical if the right ventricle contraction precedes the left ventricle contraction by more than the preprogrammed delay interval. In either case, the setting of either flip-flop 30 or 52 causes 52 causes the initiation of the timing window delay interval. When one of these flip-flop sets, the other must set within the window period, otherwise a pacing pulse will be generated in the unsensed ventricle.

The vi-bentriclar pacing control circuitry may be combined with other well-known pacer control circuitry such that the bi-ventriclar mode can be realized in combination with any other pacing mode, such as VVI, DDD, VOO. Line 58 is the logical OR of either of left ventricle event or a right ventricle event. It may be connected to other pacing control circuitry 62 in place of the signal which is normally responsive to only activity in the left ventricle. A sensed ventricle event thus inhibits the generation of a pacing trigger from another pacing circuitry and leaves the control of pacing in the alternate ventricle, as required; to the circuitry of FIG. 1. If line 58 is not activated within the escape interval of the other pacing control circuitry, a paced ventricle trigger signal on line 60 is produced which propagates through both OR gate 62 and OR gate 56 to trigger pacing pulses in both ventricles.

It is also contemplated that when a ventricular depolarization signal is sensed in one or the other of the ventricles, that a stimulating pulse may also be immediately delivered, on an unconditional basis, to both ventricles, via the implanted leads 13 and 15, thus resulting in a coordinated contraction of both ventricles.

The foregoing illustrate preferred arrangements for carrying out the objectives of this invention. Modifications and variations can obviously be made by those skilled in the art without departing from the true spirit and scope of the invention. For instance, the circuit may be employed to simultaneously pace the auricles, instead of ventricles, if such is required to improve pumping efficiency. The arrangement may also be employed as an improvement of conventional pacers thereby to improve their performance. As stated herein, the inventive arrangement can be used in an implanted device or in an external treating, diagnostic or testing device. Accordingly, the invention is limited only by the scope of the appended claims rather than by what is shown and described. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention.

Citas de patentes
Patente citada Fecha de presentación Fecha de publicación Solicitante Título
US3937226 *10 Jul 197410 Feb 1976Medtronic, Inc.Arrhythmia prevention apparatus
US4088140 *18 Jun 19769 May 1978Medtronic, Inc.Demand anti-arrhythmia pacemaker
US4332259 *19 Sep 19791 Jun 1982Mccorkle Jr Charles EIntravenous channel cardiac electrode and lead assembly and method
US4378020 *20 Ago 198129 Mar 1983Telectronics Pty. Ltd.Dual chamber pacer
US4458677 *19 Nov 198110 Jul 1984Mccorkle Jr Charles EIntravenous channel cardiac electrode and lead assembly and method
US4548203 *25 Jun 198422 Oct 1985Purdue Research FoundationSequential-pulse, multiple pathway defibrillation method
US4624260 *7 May 198525 Nov 1986Intermedics, Inc.Pacemaker with conditional atrial tracking capability
US4774950 *6 Oct 19874 Oct 1988Leonard BloomHemodynamically responsive system for and method of treating a malfunctioning heart
Otras citas
Referencia
1Aranda, et al., "A New Pacemaker for Simultaneous Biventricular Stimulation . . . ", Clin. Res., 24, 206A.
2Befeler, et al., "Programmed Simultaneous Biventricular Stimulation . . . ", Eur. J. of Cardiology, 1979, pp. 369-378.
3Haas, et al., "Pacemaker-Induced Cardiovascular Failure", Am. J. of Cardiology, 1974, pp. 295-299.
4Haas, et al., "Pacemaker—Induced Cardiovascular Failure", Am. J. of Cardiology, 1974, pp. 295-299.
5 *Incomplete Filling and Incoordinate Contraction as Mechanisms of Hypotension during Ventricular Tachycardia in Man, by Joao A. Lima et al., Circulation, vol. 68, No. 5 (1983).*
6Lister, et al., "Effect of Pacemaker Site in . . . Heart Block", Am. J. of Cardiology, 1964, pp. 494-503.
7Mann, et al., "Entrainment of Ventricular Tachycardia", J. Am. College of Cardiology, 1985, pp. 781-787.
8Schlant et al., "Modification of the Law of the Heart: Influence of Early Contracting Areas (P)", Circulation, Supp. III, 1964, pp. III-153 & 154.
9Tyers, "Ventricular Stimulation After A-V Block", J. Thoracic and Cardiovas. Sur., 1970, pp. 211-217.
10William-Olsson, ". . . Pacemaker Electrode Cite . . . ", J. Thoracic and Cardiovas. Surg., 1963, pp. 618-621.
11Zile, et al., "Relaxation and Filling Rates During Asynchrony", J. Am. Coll. Cardiol., 1987, pp. 702-709.
Citada por
Patente citante Fecha de presentación Fecha de publicación Solicitante Título
US670605921 Nov 200116 Mar 2004Cardiac Pacemakers, Inc.Reforming wet-tantalum capacitors in implantable medical devices
US676326722 Ene 200213 Jul 2004Cardiac Pacemakers, Inc.Ventricular conduction delay trending system and method
US679573426 Dic 200021 Sep 2004Cardiac Pacemakers, Inc.Method and apparatus for display of ventricular electrograms
US692035517 May 200219 Jul 2005Cardiac Pacemakers, Inc.Multi-site hybrid hardware-based cardiac pacemaker
US70433056 Mar 20029 May 2006Cardiac Pacemakers, Inc.Method and apparatus for establishing context among events and optimizing implanted medical device performance
US705084915 Jun 200423 May 2006Ebr Systems, Inc.Vibrational therapy device used for resynchronization pacing in a treatment for heart failure
US713198816 Mar 20047 Nov 2006Greatbatch Ltd.Reforming wet-tantalum capacitors in implantable medical devices
US714291416 Ago 200228 Nov 2006Cardiac Pacemakers, Inc.Mode transition timing for synchronized pacing
US71712674 Ago 200330 Ene 2007Greatbatch, Inc.Reforming wet-tantalum capacitors in implantable defibrillators and other medical devices
US718128526 Dic 200020 Feb 2007Cardiac Pacemakers, Inc.Expert system and method
US723124924 Jul 200312 Jun 2007Mirowski Family Ventures, L.L.C.Methods, apparatus, and systems for multiple stimulation from a single stimulator
US734973424 Dic 200325 Mar 2008Cardiac Pacemakers, Inc.Method and apparatus for delivering defibrillation shock therapy while reducing electrical dispersion due to ventricular conduction disorder
US73830887 Nov 20013 Jun 2008Cardiac Pacemakers, Inc.Centralized management system for programmable medical devices
US746803218 Dic 200223 Dic 2008Cardiac Pacemakers, Inc.Advanced patient management for identifying, displaying and assisting with correlating health-related data
US753622317 Ago 200419 May 2009Cardiac Pacemakers, Inc.Mode transition timing for synchronized pacing
US755863127 Sep 20067 Jul 2009Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US7561914 *20 Dic 200514 Jul 2009Medtronic, Inc.Method of continuous capture verification in cardiac resynchronization devices
US760662121 Dic 200520 Oct 2009Ebr Systems, Inc.Implantable transducer devices
US761009221 Dic 200527 Oct 2009Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US764710218 Nov 200512 Ene 2010Impulse Dynamics N.V.Cardiac contractility modulation device having anti-arrhythmic capabilities and method of operating thereof
US766210418 Ene 200516 Feb 2010Cardiac Pacemakers, Inc.Method for correction of posture dependence on heart sounds
US767857311 Abr 200516 Mar 2010Pluristem Ltd.Method of preparing a conditioned medium from a confluent stromal cell culture
US76805303 May 200616 Mar 2010Cardiac Pacemakers, Inc.Method and system for display of cardiac event intervals in a resynchronization pacemaker
US770239210 Feb 200620 Abr 2010Ebr Systems, Inc.Methods and apparatus for determining cardiac stimulation sites using hemodynamic data
US774281425 Abr 200622 Jun 2010Cardiac Pacemakers, Inc.Cardiac pacing system for prevention of ventricular fibrillation and ventricular tachycardia episode
US775188419 Oct 20066 Jul 2010Cardiac Pacemakers, Inc.Flexible neural stimulation engine
US776500129 Ago 200627 Jul 2010Ebr Systems, Inc.Methods and systems for heart failure prevention and treatments using ultrasound and leadless implantable devices
US776944728 Abr 20053 Ago 2010Cardiac Pacemakers, Inc.Cardiac pacemaker with table-based pacing mode implementation
US78051991 May 200628 Sep 2010Cardiac Pacemakers, Inc.Method and apparatus for establishing context among events and optimizing implanted medical device performance
US784026210 Mar 200423 Nov 2010Impulse Dynamics NvApparatus and method for delivering electrical signals to modify gene expression in cardiac tissue
US784343926 Mar 200730 Nov 2010N-Trig Ltd.Touch detection for a digitizer
US78488154 Sep 20097 Dic 2010Ebr Systems, Inc.Implantable transducer devices
US785626710 Abr 200721 Dic 2010Cardiac Pacemakers, Inc.Apparatus and method for pacing mode switching during atrial tachyarrhythmias
US78901734 Sep 200915 Feb 2011Ebr Systems, Inc.Implantable transducer devices
US789953417 Ene 20071 Mar 2011Cardiac Pacemakers, Inc.Expert system and method
US795108723 Dic 200931 May 2011Cardiac Pacemakers, Inc.Method for correction of posture dependence on heart sounds
US795348125 Oct 200031 May 2011Impulse Dynamics N.V.Anti-arrhythmic device and a method of delivering anti-arrhythmic cardiac therapy
US795349319 Dic 200831 May 2011Ebr Systems, Inc.Optimizing size of implantable medical devices by isolating the power source
US795956822 Dic 200814 Jun 2011Cardiac Pacemakers, Inc.Advanced patient management for identifying, displaying and assisting with correlating health-related data
US79837458 Ene 200919 Jul 2011Cardiac Pacemakers, Inc.Advanced patient management with environmental data
US798375918 Dic 200219 Jul 2011Cardiac Pacemakers, Inc.Advanced patient management for reporting multiple health-related parameters
US79960874 Sep 20099 Ago 2011Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US80194215 Sep 200213 Sep 2011Metacure LimitedBlood glucose level control
US802771920 Mar 200827 Sep 2011Cardiac Pacemakers, Inc.Method and apparatus for delivering defibrillation shock therapy while reducing electrical dispersion due to ventricular conduction disorder
US802772124 Mar 200327 Sep 2011Physio-Control, Inc.Balanced charge waveform for transcutaneous pacing
US803400028 Jul 200911 Oct 2011Cardiac Pacemakers, Inc.Ischemia detection using a heart sound sensor
US804321318 Dic 200225 Oct 2011Cardiac Pacemakers, Inc.Advanced patient management for triaging health-related data using color codes
US806499712 Jun 200622 Nov 2011Cardiac Pacemakers, Inc.Method and apparatus for treating irregular ventricular contractions such as during atrial arrhythmia
US809916515 Feb 201117 Ene 2012Cardiac Pacemakers, Inc.Expert system and method
US810333417 Feb 201024 Ene 2012Cardiac Pacemakers, Inc.Method and system for display of cardiac event intervals in a resynchronization pacemaker
US810803428 Nov 200531 Ene 2012Cardiac Pacemakers, Inc.Systems and methods for valvular regurgitation detection
US81354651 Dic 200813 Mar 2012Cardiac Pacemakers, Inc.System providing ventricular pacing and biventricular coordination
US816071627 Sep 201017 Abr 2012Cardiac Pacemakers, Inc.Method and apparatus for establishing context among events and optimizing implanted medical device performance
US822831116 May 200824 Jul 2012N-Trig Ltd.Touch detection for a digitizer
US823902115 Jun 20107 Ago 2012Cardiac Pacemakers, Inc.Cardiac pacing system for prevention of ventricular fibrillation and ventricular tachycardia episode
US824437116 Mar 200614 Ago 2012Metacure LimitedPancreas lead
US82497039 Feb 200721 Ago 2012Cardiac Pacemakers, Inc.Apparatus and method for ventricular rate regularization
US82497258 May 200721 Ago 2012Mirowski Family Ventures, L.L.C.Methods, apparatus, and systems for multiple stimulation from a single stimulator
US826041631 Oct 20074 Sep 2012Impulse Dynamics, N.V.Electrical muscle controller
US828051825 Ago 20062 Oct 2012Cardiac Pacemakers, Inc.Recordable macros for pacemaker follow-up
US830124731 Oct 200730 Oct 2012Impulse Dynamics, N.V.Electrical muscle controller
US830125216 Jun 201130 Oct 2012Cardiac Pacemakers, Inc.Advanced patient management with composite parameter indices
US831162918 Oct 200613 Nov 2012Impulse Dynamics, N.V.Electrical muscle controller
US83157014 Sep 200920 Nov 2012Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US832101331 Oct 200727 Nov 2012Impulse Dynamics, N.V.Electrical muscle controller and pacing with hemodynamic enhancement
US832641625 Oct 20104 Dic 2012Impulse Dynamics NvApparatus and method for delivering electrical signals to modify gene expression in cardiac tissue
US834636327 Dic 20051 Ene 2013Metacure LimitedBlood glucose level control
US835202924 May 20108 Ene 2013Cardiac Pacemakers, Inc.Flexible neural stimulation engine
US835203124 May 20078 Ene 2013Impulse Dynamics NvProtein activity modification
US838603615 Dic 201126 Feb 2013Cardiac Pacemakers, Inc.Expert system and method
US839197420 Dic 20105 Mar 2013Cardiac Pacemakers, Inc.Apparatus and method for pacing mode switching during atrial tachyarrhythmias
US839198918 Dic 20025 Mar 2013Cardiac Pacemakers, Inc.Advanced patient management for defining, identifying and using predetermined health-related events
US841733713 Jul 20099 Abr 2013Medtronic, Inc.Method of continuous capture verification in cardiac resynchronization devices
US841735014 Sep 20129 Abr 2013Cardiac Pacemakers, Inc.Recordable macros for pacemaker follow-up
US85122207 Jun 200720 Ago 2013Cardiac Pacemakers, Inc.Rate smoothing control
US854321518 Feb 201324 Sep 2013Cardiac Pacemakers, Inc.Advanced patient management for defining, identifying and using predetermined health-related events
US85485834 May 20061 Oct 2013Impulse Dynamics NvProtein activity modification
US860050416 Jun 20113 Dic 2013Cardiac Pacemakers, Inc.Physiologic demand driven pacing
US863931829 Oct 201228 Ene 2014Cardiac Pacemakers, Inc.Advanced patient management with composite parameter indices
US866649518 Mar 20054 Mar 2014Metacure LimitedGastrointestinal methods and apparatus for use in treating disorders and controlling blood sugar
US869411616 Abr 20128 Abr 2014Cardiac Pacemakers, Inc.Method and apparatus for establishing context among events and optimizing implanted medical device performance
US87001614 Sep 200315 Abr 2014Metacure LimitedBlood glucose level control
US871877323 May 20076 May 2014Ebr Systems, Inc.Optimizing energy transmission in a leadless tissue stimulation system
US874455827 Mar 20073 Jun 2014Mirowski Family Ventures, L.L.C.Method and apparatus for providing ipselateral therapy
US875589719 Nov 200717 Jun 2014Cardiac Pacemakers, Inc.System and method for remote expert-system medical device programming
US875826013 Sep 201124 Jun 2014Cardiac Pacemakers, Inc.Ischemia detection using a heart sound sensor
US87619054 Jun 201224 Jun 2014Mirowski Family Ventures, L.L.C.Methods, apparatus, and systems for multiple stimulation from a single stimulator
US879298520 Ene 200629 Jul 2014Metacure LimitedGastrointestinal methods and apparatus for use in treating disorders and controlling blood sugar
US88185118 Jun 200926 Ago 2014Cardiac Pacemakers, Inc.Automatic selection of stimulation chamber for ventricular resynchronization therapy
US88251523 Abr 20022 Sep 2014Impulse Dynamics, N.V.Modulation of intracellular calcium concentration using non-excitatory electrical signals applied to the tissue
US89349751 Feb 201113 Ene 2015Metacure LimitedGastrointestinal electrical therapy
US900877622 Oct 201214 Abr 2015Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US906115617 Jul 201423 Jun 2015Cardiac Pacemakers, Inc.Automatic selection of stimulation chamber for ventricular resynchronization therapy
US910176516 Feb 200611 Ago 2015Metacure LimitedNon-immediate effects of therapy
US928339224 Sep 201015 Mar 2016Ebr Systems, Inc.Temporary electrode connection for wireless pacing systems
US928961823 Oct 200122 Mar 2016Impulse Dynamics NvElectrical muscle controller
US93333641 Jul 201010 May 2016Ebr Systems, Inc.Methods and systems for heart failure treatments using ultrasound and leadless implantable devices
US937556618 Jul 201128 Jun 2016Cardiac Pacemakers, Inc.Device for reporting heart failure status
US948084818 Jul 20111 Nov 2016Cardiac Pacemakers, Inc.Advanced patient management with environmental data
US95664402 Sep 201114 Feb 2017Physio-Control, Inc.Balanced charge waveform for transcutaneous pacing
US95664448 May 201414 Feb 2017Mirowski Family Ventures, L.L.C.Methods, apparatus, and systems for multiple stimulation from a single stimulator
US971372312 Feb 200725 Jul 2017Impulse Dynamics NvSignal delivery through the right ventricular septum
US973113922 Dic 201515 Ago 2017Ebr Systems, Inc.Local lead to improve energy efficiency in implantable wireless acoustic stimulators
US20020128687 *17 May 200212 Sep 2002Cardiac Pacemakers, Inc.Multi-site hybrid hardware-based cardiac pacemaker
US20030004550 *16 Ago 20022 Ene 2003Cardiac Pacemakers, Inc.Mode transition timing for synchronized pacing
US20030088290 *7 Nov 20018 May 2003Spinelli Julio C.Centralized management system for programmable medical devices
US20030171791 *6 Mar 200211 Sep 2003Kenknight Bruce H.Method and apparatus for establishing context among events and optimizing implanted medical device performance
US20030208240 *3 May 20026 Nov 2003Pastore Joseph M.Method and apparatus for detecting acoustic oscillations in cardiac rhythm
US20040122294 *18 Dic 200224 Jun 2004John HatlestadAdvanced patient management with environmental data
US20040122295 *18 Dic 200224 Jun 2004John HatlestadAdvanced patient management for triaging health-related data using color codes
US20040122485 *18 Dic 200224 Jun 2004Stahmann Jeffrey E.Advanced patient management for reporting multiple health-related parameters
US20040122486 *18 Dic 200224 Jun 2004Stahmann Jeffrey E.Advanced patient management for acquiring, trending and displaying health-related parameters
US20040122487 *18 Dic 200224 Jun 2004John HatlestadAdvanced patient management with composite parameter indices
US20040193222 *24 Mar 200330 Sep 2004Sullivan Joseph L.Balanced charge waveform for transcutaneous pacing
US20040230456 *14 May 200318 Nov 2004Lozier Luke R.System for identifying candidates for ICD implantation
US20040252078 *13 Jun 200316 Dic 2004Fischer Jonathan H.Bi-directional interface for low data rate application
US20050021096 *24 Jul 200327 Ene 2005Mirowski Family Ventures, L.L.C.Methods, apparatus, and systems for multiple stimulation from a single stimulator
US20050055057 *5 Sep 200310 Mar 2005Mirowski Famliy Ventures, L.L.C.Method and apparatus for providing ipselateral therapy
US20050055058 *8 Sep 200310 Mar 2005Mower Morton M.Method and apparatus for intrachamber resynchronization
US20050131468 *15 Jun 200416 Jun 2005Ebr Systems, Inc.Vibrational therapy device used for resynchronization pacing in a treatment for heart failure
US20050180958 *11 Abr 200518 Ago 2005Technion Research & Development Foundation Ltd.Method and apparatus for maintenance and expansion of hemopoietic stem cells and/or progenitor cells
US20050181504 *11 Abr 200518 Ago 2005Technion Research & DevelopmentMethod and apparatus for maintenance and expansion of hemopoietic stem cells and/or progenitor cells
US20060136004 *21 Dic 200522 Jun 2006Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US20060136005 *21 Dic 200522 Jun 2006Ebr Systems, Inc.Implantable transducer devices
US20060161061 *21 Mar 200620 Jul 2006Ebr Systems, Inc.Vibrational therapy device used for resynchronization pacing in a treatment for heart failure
US20060161207 *20 Dic 200520 Jul 2006Busacker James WMethod of continuous capture verification in cardiac resynchronization devices
US20060212079 *18 Nov 200521 Sep 2006Routh Andre GCardiac contractility modulation device having anti-arrhythmic capabilities and method of operating thereof
US20060247708 *28 Abr 20052 Nov 2006Cardiac Pacemakers, Inc.Cardiac pacemaker with table-based pacing mode implementation
US20070043398 *19 Oct 200622 Feb 2007David TernesFlexible neural stimulation engine
US20070060961 *10 Feb 200615 Mar 2007Ebr Systems, Inc.Methods and apparatus for determining cardiac stimulation sites using hemodynamic data
US20070078490 *27 Sep 20065 Abr 2007Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US20070088393 *18 Oct 200619 Abr 2007Shlomo Ben-HaimElectrical Muscle Controller
US20070156177 *27 Dic 20065 Jul 2007Impulse Dynamics N.V.Blood glucose level control
US20070171211 *26 Mar 200726 Jul 2007N-Trig Ltd.Touch detection for a digitizer
US20070191893 *27 Mar 200716 Ago 2007Mirowski Family Ventures, L.L.C.Method and apparatus for providing ipselateral therapy background
US20070250125 *17 Ene 200725 Oct 2007Cardiac Pacemakers, Inc.Expert system and method
US20080077031 *19 Nov 200727 Mar 2008Cardiac Pacemakers, Inc.System and method for remote expert-system medical device programming
US20080167692 *20 Mar 200810 Jul 2008Cardiac Pacemakers, Inc.Method and apparatus for delivering defibrillation shock therapy while reducing electrical dispersion due to ventricular conduction disorder
US20080294208 *23 May 200727 Nov 2008Ebr Systems, Inc.Optimizing energy transmission in a leadless tissue stimulation system
US20090131993 *16 Feb 200621 May 2009Benny RoussoNon-Immediate Effects of Therapy
US20090149904 *3 Dic 200811 Jun 2009Cardiac Pacemakers, Inc.Lv unipolar sensing or pacing vector
US20090248104 *8 Jun 20091 Oct 2009Jiang DingAutomatic selection of stimulation chamber for ventricular resynchronization therapy
US20090326601 *4 Sep 200931 Dic 2009Ebr Systems, Inc.Implantable transducer devices
US20100063562 *4 Sep 200911 Mar 2010Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US20100228308 *4 Sep 20099 Sep 2010Ebr Systems, Inc.Leadless tissue stimulation systems and methods
US20100234912 *24 May 201016 Sep 2010Ternes David JFlexible neural stimulation engine
US20100298900 *2 Ago 201025 Nov 2010Yost David WCardiac pacemaker with table-based pacing mode implementation
US20110137368 *15 Feb 20119 Jun 2011Par LindhExpert system and method
US20110237967 *24 Sep 201029 Sep 2011Ebr Systems, Inc.Temporary electrode connection for wireless pacing systems
Clasificaciones
Clasificación de EE.UU.607/9
Clasificación internacionalA61N1/362, A61N1/368
Clasificación cooperativaA61N1/3627, A61N1/368, A61N1/3684
Clasificación europeaA61N1/362C
Eventos legales
FechaCódigoEventoDescripción
23 Mar 2004CCCertificate of correction