DE102011108143A1 - Modular system for producing catheter-based heart valve prostheses and prosthesis for other human flap positions, has sail sheet carrying base element and anchoring elements, which is connected to base element - Google Patents

Abstract

The modular system has a sail sheet carrying base element and an anchoring elements, which is connected to the base element outside of a body and is connected before an implantation to obtain an individual patient-specific percutaneous flap prosthesis. An independent claim is included for percutaneous flap prosthesis.

Description

It is state of the art to make heart valve prostheses such that they are loaded in a folded state on a catheter and can be brought by means of the vascular system, or via a Minithoraktomie, to the position of a diseased heart valve to restore the function of this ( Medtronic CoreValve, Edwards Lifesciences Sapien XT ). Furthermore, it is known that different size variants of such prostheses are to be used due to different anatomical conditions. Known prostheses use to achieve a holding force, among other things, the oversizing, ie pressing the prosthesis in the vessel wall by choosing a slightly larger prosthesis variant, or specially designed stent geometries and anchoring mechanisms. Such prostheses are manufactured by manufacturing in different size variants, which, however, hardly differ from each other except for the outer diameter of the prosthesis and are produced uniformly and standardized in these size variants [1].

Percutaneous prosthetic heart valves have been used since the year 2000 for minimally invasive treatment of valvular heart disease. Nowadays, they constitute an established and effective treatment option in so-called "high-risk patients" (statistically high periprocedural mortality).

Available percutaneous flap prostheses have weaknesses in anchoring action, positioning ability, effects on mitral valve function, impaired conduction system and tightness (paravalvular leakage) due to inadequate anatomical fit to [3], [4], [5].

The structure of these prostheses, also known as percutaneous flaps, can be subdivided into leaflets and stent frames. The leaflets are designed in known percutaneous prosthetic heart valves from biological material (porcine heart valves, Rinderjugularvenen, bovine or equine pericardium). The stent frame percutaneous heart valve prostheses is usually made of NiTiNol or stainless steel or a thermosetting polymer in a packing. The invention described herein relates essentially to the design of the stent frame.

Since valve diseases and vitals can be anatomically very different, it is impossible to design a uniform prosthesis for the optimal therapy of each patient and each disease. The invention described herein solves essential weaknesses of existing percutaneous flap prostheses in the field of anatomical adaptation of the prosthesis to individual needs and the problems of leakage, undesired impairment of adjacent functional anatomical structures (conduction system, mitral valve, coronary, ventricle). By structurally separating the valve function and anchoring the prosthesis, it can be adapted to specific needs with little effort. It thus becomes possible to adapt percutaneous flaps specifically to the anatomy of patients or the geometry of existing prostheses to be replaced.

The advantages of the invention are that individual, patient-specific prostheses can be produced with a manageable effort. These individual prostheses are particularly required in the field of "valve-in-valve" implantation, as a targeted adaptation of the anchoring of a replacement prosthetic valve, as described in claim 3, must ensure an optimal hold this in an existing bioprosthesis.

The modular system ( 1 ) is an invention based on observations and findings that could be made in the development and testing of percutaneous valves, as well as in the analysis of heart valve disease patterns. The principle involves assembling a percutaneous flap prosthesis of various components to yield a patient-specific and anatomically adapted prosthesis. The system can be used for all 4 heart valve positions and other humane valve positions (eg, leg vein, etc.). The shape and number of different elements attached to the base element is unlimited. It is also conceivable that special anchoring elements are designed for special application, which then become part of the modular system. The development of the elements is therefore an open process and the modular system can be extended as desired, unlike other systems for the modular production of heart valves (cf. US 6,217,611 B1 and WO 2010/079427 A1 ), the focus of this invention is not on the assembly within the body for easier implantation, but on the composition of the prosthesis.

The assembly and assembly of such a prosthesis takes place before implantation outside the body. Based on CT, MRI or ultrasound data of a patient it is determined from which standardized elements the percutaneous flap prosthesis is to be assembled. The prosthesis is then assembled from the corresponding elements. The elements are connected together to form an individual heart valve prosthesis. The compound The prosthesis is then crimped and loaded onto a catheter so that it can be advanced minimally invasively to its destination for expansion.

The main part is a sail leaf-carrying base element, which ensures the actual closing function of percutaneous flap. This base element is sail-blade-bearing and complies with the hemodynamic conditions imposed on a valve prosthesis (eg, heart valve prosthesis). The base element is provided at the top and bottom with attachment elements, which allow the connection of anchoring elements.

There is a distinction between upper and lower anchoring elements. In the case of the aortic valve, upper elements sit in the direction of the aorta and lower in the direction of the heart. Using the example of an aortic valve prosthesis, the lower anchoring element is usually chosen to be anchored in the area of the annulus (constriction below the commissures of the leaflets before the transition into the ventricle). The anchoring of the lower elements is often based on the effect of oversizing, in which the diameter is chosen to be greater than that of the vessel and the anchoring element is fixed to the wall by the higher radial force in this area. The degree of oversizing is correlated with the holding effect achieved. Local oversizing of the stent structure ensures that the anatomy of the heart is not overly disturbed (mitral valve shape preserved, compression of the nervous system avoided). Upper anchoring elements fulfill not only the task of anchoring but also a supporting function of the stent.

The percutaneous flap is thus completed by upper and lower anchoring elements, which are able to cope with different anatomical situations (stenoses, dilatations, complex anatomy, possibly also due to congenital heart defects, etc.). These elements are connected via connectors at the bottom and top of the base member with this. The anchoring elements are available as well as the base element in different sizes, so that a combination of these comes as close as possible to the anatomy of the patient.

anchoring elements

• 1. Ringe: Diese Elemente bestehen aus Ringen, die aus rautenförmigen Gliedern zusammengesetzt sind und sich wie ein Gefäßstent zusammencrimpen lassen (2a, 2b). Die genaue Rautengeometrie und die Anzahl der Rautenelemente die einen Ring bilden kann nach Bedarf angepasst werden. Es ist möglich, dass die oberen und unteren Verankerungselement bzw. unterschiedliche Prothesenanwendungen (wie z. B. Pulmonal- oder Aortenklappe) verschiedene Ringgeometrien und Rautengeometrien benötigen. Die Ringhöhe und Form (konisch, C-Form etc.) und in Folge dessen die Radialkraft und Flexibilität, können so variiert werden, dass sich ein für die jeweilige Anwendung optimiertes Verankerungselement ergibt.
• 2. Bögen: Es ist ebenfalls möglich, dass eine Verankerungsstruktur Bögen aufweist, welche leicht nach außen gestellt sind und auf der Gefäßwand aufliegen (3a, 3b). In der Regel sind die Bogen so ausgeformt, dass sie jeweils 2 Spitzen der Basisstentstruktur verbinden. Somit ergeben sich 3 Bögen oberhalb, bzw. unterhalb der Basisstentstruktur. Es ist auch möglich, dass weniger als 3 Bögen, bzw. Bögen mit unterschiedlichen Radien/Längen eingesetzt werden, um der Anatomie des Patienten gerecht zu werden. Ein Beispiel für eine solche Anwendung wäre die Berücksichtigung der Lage der Mitralklappe beim unteren Verankerungselement der Verankerung einer perkutanen Aortenklappenprothese. Diese Bogenelemente können auch gleichzeitig oben und unten mit dem Basiselement verbunden werden und radial außerhalb der Prothese liegen. In diesem Fall ergibt sich eine bogenförmige Verankerungsstruktur um das Basiselement herum, bei der auch mehrere Bögen X- oder Y-förmig miteinander verbunden werden können um eine außenliegende Gesamtstruktur zu ergeben.
• 3. Haken und Dome: Die Verankerungshaken oder Dome können am Beispiel einer Herzklappenprothese im Bereich des Klappenannulus positionert sein und ersetzen hier die Funktion der Naht bei einer chirurgisch eingesetzten Herzklappe. Diese Haken können mit Ösen ausgestattet sein, um eine gezielte Expansion und Positionierung mit Hilfe eines Fadensystems zu ermöglichen (4). Es sind auch Kombinationen aus Haken und Dornen möglich um Haltewirkung in mehrere Richtungen erzeugen zu können. Es ist weiterhin möglich, dass Verankerungselemente mit Haken und/oder Dornen in jeglichen Konfigurationen für den oberen und unteren Bereich gestaltet werden.
• 4. Seitliche Verankerungselemente: Diese Art Verankerungselement ist sowohl mit den oberen, wie auch den unteren Anbindungsstellen verbunden und bildet eine Art Spange die außerhalb der Prothese liegt. Die Form des Elements wird so gewählt, dass sie bei „valve-in-valve” Operationen genau auf die Geometrie der bereits implantierten Klappenprothese zugeschnitten ist und einen optimalen Halt innerhalb dieser verspricht. So kann der Arzt anhand der bereits implantierten (nun defekten und zu ersetzenden) Klappenprothese ein Verankerungselement auswählen, welches die Perkutanklappe in dieser verankert.

Examples of such anchoring elements are described below:

• 1. Rings: These elements consist of rings that are composed of diamond-shaped links and can be crimped together like a vascular stent ( 2a . 2 B ). The exact diamond geometry and the number of rhombic elements forming a ring can be adjusted as needed. It is possible that the upper and lower anchoring elements or different prosthesis applications (such as pulmonary or aortic valve) require different ring geometries and diamond geometries. The ring height and shape (conical, C-shape, etc.) and consequently the radial force and flexibility can be varied so that there is an optimized for each application anchoring element.
• 2. Bends: It is also possible for an anchoring structure to have bends that are slightly outwards and rest on the vessel wall ( 3a . 3b ). Typically, the arcs are shaped so that they each connect two peaks of the base stent structure. Thus, 3 arcs arise above or below the base stent structure. It is also possible that less than 3 bends, or bends with different radii / lengths are used to meet the anatomy of the patient. An example of such an application would be to consider the location of the mitral valve in the lower anchoring element anchoring a percutaneous aortic valve prosthesis. These arch elements can also be connected at the same time top and bottom with the base member and lie radially outside the prosthesis. In this case, an arcuate anchoring structure results around the base element, in which several arcs can also be connected to one another in an X- or Y-shape in order to give an external overall structure.
• 3. Hook and Dome: The anchoring hooks or domes can be positioned in the area of the valve annulus using the example of a heart valve prosthesis and here replace the function of the suture in a surgically inserted heart valve. These hooks can be equipped with eyelets to enable a targeted expansion and positioning by means of a thread system ( 4 ). There are also combinations of hooks and thorns possible to produce holding effect in several directions. It is also possible that anchoring elements with hooks and / or spikes can be designed in any upper and lower configuration.
• 4. Lateral anchoring elements: This type anchoring element is connected to both the upper and the lower attachment points and forms a kind of clasp which lies outside the prosthesis. The shape of the element is chosen so that it is precisely tailored to the geometry of the already implanted valve prosthesis in "valve-in-valve" surgery and promises optimal retention within it. So The doctor can select an anchoring element based on the already implanted (now defective and to be replaced) valve prosthesis, which anchors the percutaneous flap in this.

Connection of the items:

The attachment of the anchoring elements can be fabric, form or non-positively designed. Possible, for example, screw, Knotverbindungen, solder joints, gluing, welding or connectors. Depending on the type of connection, the connecting pieces must be redesigned at the connection points of the anchoring elements and base stent structure ( 5 ). In any case, the connection force must be sufficient and allow a secure, durable and durable connection throughout the life cycle of the prosthesis.

Due to the modular system a variety of different designs is possible. By choosing special anchoring elements, the prosthesis geometry can be adapted to the anatomy of the patient. Upper and lower elements can be combined or only upper or lower elements can be used. The decisive factor is the resulting anatomically correct fit of the prosthesis. The prosthesis is assembled after evaluation of CT or MRI data of the patient in cooperation with the implanting physician.

An important application of such custom-made heart valve prostheses is the use in "valve in a valve" implantation, in which the function of a degenerated and no longer functional prosthetic heart valve is replaced by a minimally invasive heart valve prosthesis. Due to the adaptable prosthesis geometry, special percutaneous flap variants for the respective previously used bioprostheses can be created. These are tuned in their geometry to the valve frame of bioprostheses.

This modular system allows individual prostheses without the expense of a complete customization for each patient, as can be used on an existing functional base element and a series of anchoring elements. The prosthesis can be adapted to the anatomy of the respective patient and provide a secure fit, as well as sufficient support of the surrounding vessel during stenosis ( 6 ).

When considering the economics of such a modular system is to be mentioned that the development effort for different flap systems can be reduced by the fact that the flap element must be developed only once.

Literature:

• [1] Chiam PT, Ruiz CE. Percutaneous transcatheter aortic valve implantation: evolution of the technology. At Heart J. 2009 Feb; 157 (2): 229-42 ,
• [2] Bonhoeffer P, Boudjemline Y, Saliba Z, Merckx J, Aggoun Y, Bonnet D, Acar P, Le Bidois J, Sidi D, Kachan J. Percutaneous replacement of pulmonary valve in a right ventricle to pulmonary artery prosthetic conduit with valve dysfunction. " The Lancet. 2000 Oct 21; 356 (9239): 1403-5 ,
• [3] Dwyer HA, Matthews PB, Azadani A, Ge L, Guy TS, Tseng EE. Migration forces of transcatheter aortic valves in patients with noncalcific aortic insufficiency. J Thorac Cardiovasc Surg. 2009 Nov; 138 (5): 1227-33. Epub 2009 Sep 13 ,
• [4] Jilaihawi H, Chin D, Vasa-Nicotera M, Jeilan M, Spyt T, Ng GA, Bence J, Logtens E, Kovac J. Predictors for permanent pacemaker requirement after transcatheter aortic valve implantation with the CoreValve bioprosthesis. At the Heart J. 2009 May; 157 (5): 860-6 ,
• [5] Lutter G, Cremer J. Invited commentary. Ann Thorac Surg. 2009 Feb; 87 (2): 601-2 ,

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 6217611 B1 [0007]
• WO 2010/079427 A1 [0007]

Cited non-patent literature

• Medtronic CoreValve, Edwards Lifesciences Sapien XT [0001]

Claims (3)

Modular system for producing minimally invasive, catheter-based prosthetic heart valves and prostheses for other humane valve positions, consisting of a sail-blade-carrying base member and periphery (anchoring elements) which can be connected to the base member outside the body and prior to implantation to obtain an individual patient-specific percutaneous flap prosthesis. Percutaneous flap prostheses which are manufactured according to claim 1 and are assembled on the basis of patient data in such a way that they do justice to the patient-specific anatomical morphology of the place of use (heart valve, vein, etc.). Percutaneous flap prostheses which are manufactured according to claim 1, whose periphery is designed such that an optimal anchoring in an existing heart valve prosthesis ("valve-in-valve" implantation) becomes possible.

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