WO2007144121A1

WO2007144121A1 - Device for treatment of mitral valve insufficiency

Info

Publication number: WO2007144121A1
Application number: PCT/EP2007/005120
Authority: WO
Inventors: Zsolt Nagy; Gerhard Ziemer
Original assignee: Eberhard-Karls-Universität Tübingen Universitätsklinikum
Priority date: 2006-06-16
Filing date: 2007-06-11
Publication date: 2007-12-21
Also published as: DE102006028964A1

Abstract

The present invention relates to a device for correcting insufficiency of the mitral valve between the left atrium and left ventricle of a heart. The device comprises at least two tendon-like elements (36, 37), each with a first end and a second end, and it also comprises a first anchoring element (46) provided on the respective first ends of the tendon-like elements, and a second, curved anchoring element (30) mounted in the area of the second ends of the tendon-like elements. The device according to the invention is furthermore used in a method for correcting insufficiency of the mitral valve of a heart, in which method two tendon-shaped threads are introduced between the anterior ring of the mitral valve and the posterior wall of the left ventricle, in the area of the origin of the papillary muscles.

Description

Device for the treatment of mitral valve insufficiency

The present invention relates to a device for correcting insufficiency of the mitral valve of a heart.

The heart is generally divided into a right and a left half of the heart, each consisting of a chamber (ventricle) and an atrium (atrium). The blood can only flow in one direction in the heart spaces, since there are heart valves between the atria and chambers and the vessels adjoining the ventricles, which work like valves. The upper and lower vena cava enter the right atrium and deliver the oxygen-depleted (venous) blood from the great circulation to the heart. Between the right atrium and the right ventricle is the tricuspid valve, which prevents a backflow of blood into the atrium like a valve during chamber contraction. It consists of three components that are attached to the musculature of the chamber via tendon threads (hence the sails flap). The two lung artery leave via a common trunk then the right chamber. These lead the oxygen-poor blood to the pulmonary circulation. The oxygen-rich (arterial blood) from the pulmonary circulation then flows through the pulmonary veins to the left atrium. From here it passes through another sail flap, the mitral valve to the left ventricle. The outflow is via the aorta, which has a flap like the pulmonary artery (aortic valve).

The mitral valve is thus located between the left atrium and the left ventricle of the heart. Due to the significant pressure differences between systole and diastole on the one hand and the left atrium and the left ventricle on the other hand, the mitral valve is exposed to a very large pressure load. Normally, this pressure load is overcome by the construction of the mitral valve, which consists of the four main elements mitral ring, mitral sails and the papillary muscles with the chordae tendiae (tendon sutures).

The mitral ring consists of compact connective tissue, which continues into the fibrosa of the mitral leaflets; it represents a connective tissue connection between the atrial and ventricular myocardium. The mitral ring belonging to the heart skeleton thus serves among other things to support the mitral sails. Since the mitral ring corresponds more to a curtain than to a ring structure, the term "aorto-ventricular membrane" is often used for this element.

The two sails of the mitral valve are attached to the wall of the left ventricle via the papillary muscles with the chordae tendiae, which normally prevents the mitral sails from being repulsed into the left atrium during systole. From the Papillarmuskeln emanates the majority of the Chordae tendiae. The papillary cycles are primarily used to regulate the tension of the chordae, thus enabling optimum valve closure. Furthermore, the papillary muscles reduce the mechanical stress on the chordae tendiae.

In mitral valve insufficiency, the heart valve between the left atrium and the left ventricle, the mitral valve, is no longer able to move completely close. As a result, part of the blood from the left ventricle flows back into the left atrium during the heartbeat. This blood flows back through the mitral valve into the left ventricle prior to the next heartbeat - along with the newly arriving blood from the lungs. So it practically shuttles back and forth between left atrium and left ventricle. On the one hand, this limits the capacity of the left ventricle, and on the other hand, the left atrium is distended by the blood flowing back and forth.

Furthermore, blood can back up into the lungs due to the larger amount of blood in the left atrium. There, the blood pressure increases and water is forced out of the blood into the lungs. Prolongation of this increased lung pressure and prolonged accumulation of water in the lungs make it increasingly difficult for the right ventricle to pump blood into the lungs. As a result, the right ventricle is overloaded and there is a right heart failure. The main symptom of right heart failure is the accumulation of water in the tissue, e.g. in the form of swollen ankles.

Lighter forms of mitral valve insufficiency usually do not cause discomfort because the distensible wall of the left atrium can temporarily compensate for the increased load. As the disease progresses, cardiac arrhythmias, atrial fibrillation, dyspnoea, and edema may occur as symptoms, as well as the accumulation of blood clots in the dilated left atrium, with the risk that they may reach the blood vessels of the brain with the bloodstream and a stroke there trigger.

In patients with severe mitral regurgitation, the indication for heart valve surgery should be considered. In this case, either a reconstruction of the flap is made, or used an artificial heart valve. Basically, valve reconstruction is preferred because it results in less impairment of cardiac function and does not require sustained dilution of blood in preserved sinus rhythm. However, it is especially prevalent in heavily shrunken, calcified or even destroyed flap sails not possible, so that only a replacement valve comes into question.

Mitral valve insufficiency is caused by several diseases that affect the function of the valve in different ways. While valve inflammation literally destroys the sails, a degenerative disease of connective tissue causes overstretching of the leaflets and chordae, provoking a setback. The ischemic mitral regurgitation that occurs as a result of circulatory disorders basically affects the muscular components of the valve, namely the papillary muscles and the ventricular wall, where the former originate. Ischemic mitral regurgitation can be divided into acute and chronic forms.

The acute form is often a severe insufficiency caused by papillary muscle tears and requires immediate replacement of the irreversibly damaged valve with an artificial valve.

According to recent findings, the cause of chronic mitral valve insufficiency is dysfunction of the posterolateral ventricular wall. As already mentioned above, akinesia or dyskinesia exerts a pull on the papillary muscles during systole and thus on the valve leaflets. The consequence of this apicolateral traction is a deficient systolic coaptation of the mitral valve leaflets and a significant mitral valve insufficiency. This disease is better for reconstructive surgical procedures. However, the correction of chronic ischemic mitral regurgitation is often unsuccessful with existing techniques. The commonly used reduction annuloplasty has a persistence or recurrence rate of 30% as it only treats the annular (ring) component, which according to recent studies plays only a secondary role in chronic ischemic-functional mitral valve regurgitation. Classical concepts regarding the physiology of ischemic mitral regurgitation have attributed these to dysfunction of the papillary muscle, combined with enlargement of the mitral ring. Ring enlargement was performed with different types of ring dentures, ligaments or sutures, with little promising results.

A reversal in the treatment of mitral regurgitation was the introduction of "diminishing" annuloplasty, in which a ring was implanted that was two smaller than the size actually measured, a feature characterized by its simplicity and the fact that the Despite this new technique, persistent and recurrent insufficiencies were observed, often just months after surgery, in 30% or even more of the patients.

Thus, various publications and techniques are currently known in the art that address ischemic mitral regurgitation via a subvalvular approach. At present, four different approaches are known.

For example, the device "Coapsys" consists of two epicardial pads and an expanded polytetrafluoroethylene-coated, braided, subvalvular polyethylene band The two pads are placed on the surface of the heart with the subvalvular band passing through the ventricle two heads, a "ring head" and a "papillary muscle head" designed to cause the ring head and the papillary muscle head to deform with respect to the mitral ring and to the papillary muscle when the anterior and posterior pedi are contracted For example, apparatus is described in more detail in Grossi EA et al., "Intraoperative Effects of the Coapsys Annuloplasty System in a Randomized Evaluation (RESTOR-MV) of Functional Ischemic Mitral Regurgitation," Ann Thorac Surg. 2005; 80: 1706-1710.

As another device, the so-called posterior ped is known, which is an expandable intrapericardial pedis which is placed on the epicardial surface of the affected region. Further, Krön et al., "Surgical relocation of the posterior papillary muscle in chronic ischemic mitral regurgitation," Ann. Thorac. Surg. 2002; 74: 600-601, described a polypropylene suture provided between the papillary muscle tip and the ring. to correct the posterior papillary muscle in its position.

In addition, Liel-Cohen et al., "Design of a new surgical approach to ventricular remodeling to relieve ischemic mitral regurgitation: insights from 3-dimensional echocardiography," Circulation 2000; 101: 2756-63, has published a new surgical technique from outside the beating heart, without the use of a cardiopulmonary bypass The surgical technique is based on the reduction of the interpapillary distance.

Although some methods and devices for correcting ischemic mitral regurgitation have been known and described in the art, many of the methods and devices still suffer from disadvantages that lead to unsatisfactory results and often require the use of a heart-lung machine.

It is therefore an object of the present invention to provide a novel device with which the disadvantages of the devices and surgical techniques known in the art can be overcome, without the necessity of using a heart-lung machine.

According to the present invention, this object is achieved in that the device mentioned above has at least two chord-like elements, each having a first end and a second end, further provided at the respective first ends of the chord-like elements anchoring element, as well as in the region of the second ends the tendon-like elements attached second curved anchoring element. The object underlying the invention is further achieved by a method for correcting the insufficiency of the mitral valve of a heart, wherein at least two tendon-like threads between the anterior part of the mitral valve annulus and the posterior wall of the left ventricle are introduced in the region of the two papillary muscles, wherein the tendon-like Threads are secured to the posterior wall of the left ventricle via a first anchoring element and to the mitral valve annulus via a second anchoring element.

The object of the invention is completely solved in this way.

With the device according to the invention is achieved that the architecture of the mitral valve can be restored to the beating heart and stabilized without having to use a heart-lung machine.

It is understood that the device according to the invention can also be used together with coronary artery bypass surgery in order to simultaneously correct the mitral valve insufficiency.

Since the open heart procedure can be performed without cardiopulmonary bypass, it is particularly advantageous because cardiac arrest, which is a prerequisite for open heart surgery, is a significant risk factor in mitral valve heart failure.

With the present device it is achieved that the symmetry of the architecture of the left ventricle is restored by aligning the base of both papillary muscles with respect to a reference point, and additionally establishing an extracardiac tensile force to reduce the interpapillary distance. As a result, transventricular threads, which reduce the longitudinal diameter of the dilated ventricle, are thus laid on the basis of the device according to the invention. In the present case, "bent" means any shape that does not run straight, similar to a tube section whose two ends can be guided different close to each other The bend is preferably adapted to the respective shape of the mitral valve ring.

In the device according to the invention it is preferred if the first anchoring element is designed for attachment to a rear wall of the left ventricle of the heart, and that the second anchoring element is designed for attachment to the ring of the mitral valve.

This embodiment has the advantage that not only can the transverse diameter of the ventricle be reduced, but the entire ventricle is adapted to the respective requirements.

In particular, it is preferred if the second anchoring element has at least two depressions, and that the at least two tendon-like elements each have a sealing element at their second end, which are designed for introduction into the depressions of the second anchoring element.

This embodiment has the advantage that the second anchoring element is adapted to the shape of the mitral valve annulus, and conforms to the outer shape of the aortic root and the left atrium. The anchoring element has two recesses or recesses into which the sealing elements of the chord-like elements fit. This design prevents the tendon-like elements in this area from cutting or deforming the tissue material, which could affect the function of the aortic valve.

The sliding strip-shaped design of the first anchoring element has the advantage that the anchoring element has two halves which slide into one another, and which can each be adapted to the necessary correction of the interpapillary distance. In the present case, the anchoring element is also referred to as a ventricular strut which has two circular pressure pads which consist of a hemostatic material and which play a stabilizing role. The two pads are mounted on the strut via two telescoping elements, so that the ventricular strut has an overall slider-shaped character.

The tendon-like elements anchored in the first anchoring element, ie the mitral valve annulus strut, are guided into the ventricular strut, in particular through the two circular pads.

In particular, in one embodiment, it is preferred if the first anchoring element has two circular pressure pads, which are mounted so as to be displaceable relative to one another on a strip.

The tendon-like elements are thereby passed through these circular pressure pad and have in a preferred embodiment at least one of its first ends means for constricting or pressing.

Such means may be, for example, tourniquet-type devices by means of which the lengths of the tendon-like elements can be lashed.

In another embodiment, it is preferred if the chordal elements comprise a material selected from the group consisting of polypropylene, polytetrafluoroethylene, polyurethane, or mixtures thereof.

It is further preferred if the first and the second anchoring element comprise a material which is selected from the group comprising Teflon, or mixtures thereof. As already mentioned above, the present invention also relates to a method for correcting the insufficiency of the mitral valve of a heart. In this case, at least two tendon-like threads - for example, via appropriate insertion needles - introduced between the front part of the mitral valve ring and the posterior wall of the left ventricle in the region of the two papillary muscles. The tendon-like threads are attached to the posterior wall of the left ventricle via a first anchoring element - for example via a sliding strip-shaped element, namely a ventricular strut - and with its second end on the mitral valve ring via a second anchoring element, which is the shape of the mitral valve annulus is adjusted. This anchoring element in this case has two recesses into which the two sealing pieces of the chord-like elements, or neochordae, fit.

Overall, in the method according to the invention it is preferable if it comprises the following steps: a) introducing at least two tendon-like threads in a modified Seldinger technique between the anterior mitral valve annulus and the posterior wall of the left ventricle in the region of the papillary muscle origin, and b) donning the threads to the desired setting of the distance between the papillary muscle and mitral valve ring.

Furthermore, the invention relates to the use of the device for the correction of insufficiency of the mitral valve of the heart.

It is understood that the features mentioned above and those to be explained below can be used not only in the particular combination given, but also in other combinations or alone, without departing from the scope of the present invention.

The invention will be elucidated from the following description and the accompanying drawings. Show it: Fig. 1 is a schematic representation of a cross section through a heart of a

People;

2a shows the second anchoring element of the device according to the invention for attachment to the mitral valve ring.

FIG. 2b shows another view of the second anchoring element from FIG. 2a; FIG. and

Fig. 2c, the first anchoring element of the device according to the invention for attachment to a rear wall of the left ventricle.

For a better understanding, the general structure of a human heart will be explained first with reference to FIG. FIG. 1 shows a schematic cross-section through the heart of a human, which is identified by 10. The left atrium (11) and the left ventricle (12), the right atrium (13) and the right ventricle (14) with 14. The oxygen-poor blood is through upper and lower vena cava 15 and 16 fed to the right atrium 13. The blood passes from the right atrium 13 via the tricuspid valve 17 into the right ventricle 14 and from there via the pulmonary valve 18 into the pulmonary veins 19. The oxygenated blood in the lung is then transferred to the left atrium 11 and via the mitral valve 20 into the left ventricle 12, where it is pumped via the aortic valve 22 into the aorta 24.

FIGS. 2a, 2b and 2c show different views of an embodiment of the device according to the invention. In this case, the same features are provided with the same reference numerals in these figures.

In Figs. 2a and 2b different views of the end of an embodiment of the device according to the invention are shown, which has the second anchoring element, namely a kind of ring strut. In Fig. 2a, this anchoring element, or the ring strut, indicated generally at 30 and viewed from the anterior side. The anchoring element 30 is of a shape such that it can adapt to the aorto-ventricular membrane. With reference to Figure 2b, the anchoring element 30 has a curved shape and two recesses or recesses 32, 33 provided on the posterior side. The two depressions or recesses 32, 33 in this case have a shape which is adapted to sealing elements 34, 35. These sealing elements 34, 35 are located at one end of the see-like elements 36, 37, the neochordae. In the composition of the device according to the invention thus the see-like elements 36, 37 are guided through the recesses 32, 33 of the bent portion of the ring strut 30 until the sealing elements 34, 35 located at the end thereof fit into the depressions 32, 33 corresponding to their shape ,

This design of the anchoring element 30 on the mitral valve ring is intended to prevent, for example, after an insertion of the tendon threads, they cut or deform the tissue in this area, which could impair the function of the aortic valve.

In Fig. 2c, the first anchoring element of the device according to the invention is shown, which is attached to a rear wall of the left ventricle of the heart and is adapted to the shape of this wall. The anchoring element 40 is designed as a sliding strip-shaped strut and has two elements 42, 43, which can be at least partially pushed into each other, which is indicated by the arrow 41. At the ends of the two elements 42, 43 in each case a pressure pad 44, 45 is provided, which come to rest against the ventricular wall. Furthermore, the tendon threads 36, 37 are guided by these pressure pads 44, 45, which are fixed via tourniquets 46, 47, whereby they rest smoothly and firmly against the anchoring element. The pressure pads 44, 45 are soft and made of a hemostatic material, preferably Teflon. The distance between the anchoring element 30, which is fixed to the mitral valve ring, and the anchoring element 40, which is mounted in a wall of the ventricle, is regulated by Tourniquets. If the operation is performed laterally to the left, the tourniquets will be provided on the ventricular side, whereas in a middle sternotomy the tourniquets will be provided at the end of the ring, where then the tightening of the tendon-like strands will be accomplished.

The pressure pads applied to the outer surface of the heart also eliminate the need to attach sutures to the myocardial wall. With the sliding strip-shaped anchoring element 40 can further be ensured that the interpapillary distance can be changed, since, for example, by the telescoping of the two elements 42, 43 and the pressure pad 44, 45 mounted on these elements 42, the distance between the origins of the papillary muscles can be reduced.

The introduction of the device according to the invention into the heart can take place, for example, via a middle sternotomy, the access being facilitated by gently pulling aside the aorta and the superior vena cava. First, a fixation needle is introduced via a "reference point." This represents, for example, the anatomical point between the mitral and aortic valve. This is easily accessible from a surgical point of view, and due to the two elevations of the left coronary and non-coronary sinus on the This point consists of a very strong fibrous structure, with the intertrigonal triangle between the adjacent left and non-coronary sinuses being large enough to allow placement of the planned sutures without injuring the adjacent aortic valve leaflets The area can be reached via a middle sternotomy or via a left lateral thoracotomy.

To introduce the device according to the invention, the two elevations of the adjacent sinuses are identified. Subsequently, a bent introduction Introduced direction with needle at this point, and the position in the heart confirmed by the back-flow through the needle. As a control, a pressure valve can be attached to the needle to verify the position in the heart. The stoker has a curved shape to allow the direction of its intraventricular tip from the left side.

The fixation needles are sufficiently elastic that they can be inserted through the curved introducer while being rigid enough to pierce the posterior ventricular wall. These are about 20 to 25 cm long so that they can bridge the distance from the reference point to the origin of the papillary muscle. At the end of the needles, the tendon-like string elements (serving as Neochordae) are attached, which is made of polypropylene or PTFE, for example. PTFE sutures are used in the prior art to replace torn or elongated tendons for extended periods of time.

The two anchoring elements are respectively fixed to the mitral valve annulus or to a posterior wall of the left ventricle of the heart. By the see-like elements, the anchoring elements are connected, wherein the distance between these, for example, can be controlled via tourniquets. As a result, transventricular threads, which reduce the longitudinal diameter of the dilated ventricle, are thus laid on the basis of the device according to the invention.

Therefore, with the method according to the invention, the architecture of the beating heart mitral valve can be restored and stabilized without the need for a cardiopulmonary bypass.

In summary, the principle of the procedure is the insertion of two neochordae between the anterior portion of the mitral valve annulus and the posterior wall of the left ventricle near the origin of the two papillary muscle. Under echocardiographic control, the two neochordae are then treated according to the Tourniquet principle (either from the annulus or from the ventricular wall) for so long. until the distance between the papillary muscle and mitral valve annulus has been restored so that the tightness of the mitral valve is restored. The additional sliding bar, or the first anchoring element, which is attached to the posterior wall of the ventricle, the possibly pathologically modified, interpapillary distance can be further reduced.

Claims

claims

A device for correcting insufficiency of the mitral valve between the left atrium and the left ventricle of a heart, the mitral valve comprising a ring, two leaflets and papillary muscles, characterized in that the device comprises at least two tendon-like elements each having a first end and a second end and a first anchoring element provided at the respective first ends of the chord-like elements, and a second bent anchoring element mounted in the region of the second ends of the chord-like elements.

2. Device according to claim 1, characterized in that the first anchoring element is designed for attachment to a rear wall of the left ventricle of the heart, and that the second anchoring element is designed for attachment to the ring of the mitral valve.

3. Apparatus according to claim 1 or 2, characterized in that the second anchoring element has at least two recesses, and that the at least two chord-like elements each have at their second end a sealing element which are provided for insertion into the recesses of the second anchoring element.

4. Device according to one of claims 1 to 3, characterized in that the first anchoring element is strip-shaped, in particular sliding strip-shaped.

5. Device according to one of claims 1 to 4, characterized in that the first anchoring element comprises two circular pressure pad, which are mounted against each other slidably mounted on a bar.

6. Device according to one of claims 1 to 5, characterized in that the chordal elements Tournizets have at least one of its first ends.

7. Device according to one of claims 1 to 6, characterized in that the chordal elements have at their first end means for constricting o- pressing off.

8. Device according to one of claims 1 to 7, characterized in that the chordal elements comprise a material which is selected from the group comprising polypropylene, polytetrafluoroethylene, or mixtures thereof.

9. Device according to one of claims 1 to 8, characterized in that the first anchoring element comprise a material which is selected from the group comprising Teflon, or mixtures thereof.

10. Device according to one of claims 1 to 9, characterized in that the second anchoring element comprises a material which is selected from the group comprising, or mixtures thereof.

11. A method for correcting the insufficiency of the mitral valve of a heart, characterized in that at least two tendon-like threads between the anterior part of the mitral valve annulus and the posterior wall of the left ventricle are introduced in the region of the two papillary muscle, wherein the tendon-like threads on the rear wall of the left ventricle be attached via a first anchoring element and the mitral valve annulus via a second anchoring element.

12. The method according to claim 11, characterized in that it comprises the following steps: a) introducing at least two tendon-like threads in a modified Seldinger technique between the anterior mitral valve annulus and the posterior wall of the left ventricle in the region of the origin of the papillary muscle, and

b) Tightening the sutures until the desired adjustment of the distance between papillary muscle and mitral valve annulus.

13. Use of the device according to one of claims 1 to 10 for the correction of an insufficiency of the mitral valve of the heart.

14. Use of the device according to one of claims 1 to 10 in a method according to one of claims 11 or 12.