DE102012003021A1 - Intravascular occlusion device for closing left atrial appendage during treatment of atrial fibrillation, has distal end that is arranged above diaphragms so as to seal atrial appendage entrance - Google Patents

Abstract

The occlusion device has two main portions that are provided at proximal end and distal end respectively. The distal end is arranged above the diaphragms so as to seal atrial appendage entrance (5). A lid is provided at the proximal end of occlusion device. A fastening hook provided in hook region is arranged towards the lid. An independent claim is included for method for manufacturing intravascular occlusion device.

Description

The present invention relates to an occlusion device for the interventional closure of the left atrial appendage. LAA stands for "left atrial appendage" and a manufacturing process for such an occlusion device.

Usually, a common occlusion device is brought into an elongated form by means of deformation and heat treatment methods and introduced through a catheter into the cardiovascular system. In this case, the catheter introduced from the right groin vein into the right atrium is guided through a transseptal puncture of the anterior chamber septum into the left atrium of the heart. Upon exiting the catheter tip, the occlusion device z. B. in the atrial appendage to its predetermined shape is anchored at the destination and released after checking the correct position and location. Within a few weeks, the occlusion device grows and is overgrown by the body's own endothelial cells.

Echocardiographic studies have shown that embolisms responsible for the increased risk of stroke in people with atrial fibrillation originate from the left ear in more than 90% of cases. Since this protuberance of the left atrium is a remnant of embryonic development and has no function, it makes sense to close it. However, open heart surgery would be too risky an intervention.

So far, the following different closure devices have been used to close the left atrial appendage:
With the Percutaneous LAA Transcatheter Occlusion (PLAATO) device from Ev3 Inc. (see also EP 1852141 A2 ), the left ear of the heart was successfully closed for the first time in 2000 in about 100 patients. In particular, because of various perforations of the pericardium, caused by located on the implant barbs, but there were no further applications. Starting from the PLAATO device, such closure systems are referred to as LAA occluders.

In a subsequent LAA closure system, the Watchman Occluder from Atritech, such perforations can not be ruled out. Added to this is the problem of inadequate localization. The Watchman Occluder tends to slide too deep into the heart ear.

From AGA Medical Corp. At the end of 2008, an LAA occluder was approved for Europe. With this device, however, only a certain number of atrial ears can be closed with an optimal shape.

From the pamphlets WO 2007/140797 A1 . DE 10 2005 053 906 A1 and WO 2008/125689 A1 Occlutech GmbH describes occlusion instruments for closing a cardiac ear, for example nitinol, which consist of a hollow braid of thin wires. However, such Occlusionsinstrumente can only develop in the free environment of blood, such. As in the closure of atrial septal defects. In the very tight envelope of the left atrial appendage of the Occlusionsinstruments is severely hampered in the initial form, also the distal retention areas according to WO 2007/140797 A1 (one or two hat-shaped brims) and WO 2008/125689 A1 (spherical shape, hat and funnel shape ) is not suitable for safely anchoring the occlusion device in the auricle. The application of a fixative according to WO 2007/140797 A1 with a polymer network preferably formed in the atrial appendage of the patient from a drainable polyreaction mechanism for forming a frictional connection between the mesh of the occlusion device and the atrial appendage, ie the use of a plastic adhesive, is differentiated from a medical point of view consider and has led to no practical applications.

The above closure devices have significant disadvantages:
In these occlusive devices, the bulging of the left auricle and friction between the occlusion devices and the pericardium can cause very painful inflammation of the pericardium. The hooks used to secure the occlusion devices can cause perforation of the pericardium. The danger of thrombosis due to the coupling, which partly projects far into the left atrium, at the proximal end of the occlusion instruments is relatively high. Localization problems also occur with the Watchmann device. Furthermore, these devices have the disadvantage that the catheter is by its positioning in the left atrium in the direction of its longitudinal axis at an unfavorable angle to the position of the Occlusionsinstruments in the final position in the left auricle, ie both axes are almost at right angles to each other. This positioning leads to significant disability during the course of implantation and can lead to perforation of the left pericardium by piercing the wall of the left atrial appendage.

The object of the invention is therefore to avoid the disadvantages described in the prior art and in particular to provide an improved, easily and safely implantable occlusion device. Another object is a simple and inexpensive method for producing such an occlusion device.

The object is achieved by an occlusion device according to claim 1 and a manufacturing method according to claim 10. Advantageous embodiments can be found in the dependent claims.

The occlusion device according to the invention for occluding a cardiac ear comprises a first section at a proximal end of the occlusion device, which is adapted to the diameter of a cardiac ear entrance, and a second section, which is adapted to the length of the cardiac ear. The closure of the atrial appendage by the occlusion device is achieved in that in the second section, two membranes arranged above or behind one another at a distal end of the occlusion device correct the occlusion device such that the atrial appendage is occluded by the occlusion device becomes.

These membranes preferably have a longitudinal structure on their lateral side and a mesh or lattice structure on their front sides. The front sides thus enable a stable cover (stamping function). The lateral sides are very easy to compress in length and indeed by a slight pressure on the distal end region or twist to reduce the longitudinal extent. For example, in this way, the diaphragms arranged above or behind one another act mechanically like a spring (but the spring action can also be achieved by other design adaptations), which contract by a slight axial pressure. Thus, the occlusion device adapts exactly to the depth of the cardiac ear, which is different for each cardiac ear, regardless of the diameter of the atrial appendage, which in turn decisively supports the firm anchoring of the occlusion device in the atrial appendage. This principle of action significantly differentiates the occlusion device according to the invention from all previously known occlusion devices.

It has been found that different heart ears differ significantly from one another by an individual morphology. In particular, the ratio of the diameter of the atrial appendage to the length of the atrial ear is not a constant. This means that atrial ears with a comparable atrial appendage (diameter) can be different in depth (length). To compensate for this mismatch, the present Occlusionsinstrument has two superimposed membranes, which cause with a low reaction force from the direction of the distal Herzohrendes that the Occlusionsinstrument can reduce in length, so that the opposite proximal end lid located the Herzohreingang can close exactly.

• 1. Der Durchmesser des Herzohreinganges ist kleiner als der größte Durchmesser im Herzohr (Typ Collar).
• 2. Der Durchmesser des Herzohreinganges ist größer als der größte Durchmesser im anschließenden Herzohr (trichterförmiges Herzohr)
• 3. Der Durchmesser des Herzohreinganges ist etwa gleich groß, wie in dem dahinter befindlichen Herzohr (rohrförmiges Herzohr).

In the present invention, an occlusion device is used which is self-centering and, in any embodiment, occupies an optimal position after the implantation procedure. The basic form of such a cardiac ear occlusion device results from the basic conditions of the anatomy of such a cardiac ear. Based on this, a classification into three different types of heart ear is possible:

• 1. The diameter of the Herzohreinganges is smaller than the largest diameter in the Herzohr (type Collar).
• 2. The diameter of the Herzohreinganges is larger than the largest diameter in the subsequent Herzohr (funnel-shaped Herzohr)
• 3. The diameter of the Herzohreinganges is about the same size as in the behind the Herzohr (tubular Herzohr).

Based on this morphology of the cardiac ear, three basic forms of occlusion instruments have been developed, which however are identical in their mode of action and, in particular, have corresponding double membranes at the distal end. Furthermore, the heart ears are formed differently sized within this above classification.

Preferably, the occlusion device is adapted by the shape design to occlude a cardiac ear in which the atrial appendage is smaller in diameter than the largest diameter in the atrial appendage itself (Collar type). For this purpose, after the lid initially followed by a diameter reduction, followed by an increase in diameter and the distal end towards two superimposed membranes to adjust the length of Occluders.

Preferably, the occlusion device is adapted by the shape design to close a cardiac ear, wherein the diameter of the Herzohreinganges is greater than the largest diameter of the subsequent cardiac ear (funnel-shaped). Further preferably, the Occlusionsinstrument is suitable by the shape design to close a tubular Herzohr optimally.

An exemplary occlusion device is rotationally symmetric in its basic form and has at the proximal end a circular flat stepped lid to close the transition of the left atrium to the entrance of the left atrial appendage. In the proximal retention area adjoining the lid, a diameter reduction results initially, which corresponds approximately to the diameter of the atrial appendage. Following this, the circumference of the occlusion device increases in such a way that the volume of the occlusion device approximately fills the corresponding part of the ear of the heart with the largest inner diameter in this central region. The occlusion device is compressed to about 10% of the diameter in this area by an external pressure effect from the heart ear.

Another exemplary occlusion device has self-centering features through the lid and a flat lip extending toward the distal end that is movable toward the lid, and allows for accurate positioning in the left atrial appendage, greatly simplifying the implantation procedure.

The lid preferably has a z. B. arranged in the center clutch to be connected to a suitable insertion wire. After uncoupling the delivery catheter, the coupling preferably retracts automatically into the cover in order to avoid thrombosis as far as possible.

The intravascular occlusion device is designed so that the occlusion device in the folded state by means of a catheter in the body of the patient is minimally invasive insertable and positioned in the atrial appendage of the patient. The catheter inserted into the left atrium is usually at an acute angle to the direction of the atrial appendage. The occlusion device with its lid closes flush with the atrial appendage (ie exactly in the direction of the catheter). The underlying lip is oval and gradually becomes round towards the distal end (realization of the function "self-centering"). Through a targeted lasering of the section between the lid and the beginning lip (high number of longitudinal structures), a hinge joint is actually created, so that the entire lip moves in through the self-centering in the very flat auricular congruent and on the other hand tilts the lip far down, that only very low bending stresses are caused.

A preferred occlusion device is self-expandable, is lasered from a Nitinolrohr and then converted by suitable Umformungs- and heat treatment process in a targeted final form.

However, this may not be enough to firmly anchor the occlusion device in the auricular region. Therefore, a certain number of hook elements with a length of in each case z. B. is preferably located on the outer shell of the exemplary Occlusionsinstruments, more preferably in the transition of the proximal retention area to the distal retention area or in the region of the Herzohreingangs. 1 mm, which can support the firm anchoring of the occlusion device in the left auricle. The production of the barbs is done so that lasered transverse webs are lasered at one longitudinal end and then placed in the radial direction by bending. The positioning and / or the short length of the barbs prevents perforation of the cardiac pouch.

From the exemplary dimensions of the atrial appendage with a diameter of 10 to 26.5 mm in the atrial appendage and a usable depth of the main canal of the pectoralis of 14 to 30 mm, suitably stepped sizes of suitable cardiac appendage instruments are obtained From an example suitable metallic Nitinolrohr lasered Occlusionsinstrument compressed in the compressed state by about 10%.

Superelastic metal alloys such. Nitinol, a titanium nickel alloy with an elasticity of 7% maximum elongation to the initial length, are particularly well suited to produce such a shaped body. For example, on the output side a thin-walled nitinol tube of maximum 2.5 mm diameter is used. By using a suitable laser different slots are introduced into the metal tube. Following lasering, the metal tube is widened with a mechanical device and shaped by heat treatment. The heat treatment time is at temperatures of 350 to 600 ° C and a holding time of half an hour to 2 minutes (the shorter times at higher Temperatures) feasible. The laser, stretching and heat treatment steps are carried out several times in succession until the final shape of the occlusion device has been reached. By a possible laser cutting width of up to 15 microns can be performed on the circumference of such a metal tube more than 150 cuts parallel to the longitudinal axis.

In the present occlusion device according to the invention, one or more layers of medically suitable and / or medically active materials, for example, are preferably located in the region of the atrial appendage. As patches to seal the blood flow between left atrium and left atrial appendage, so that it can no longer pass through the heart ear in the direction of the left atrium. As a material is z. As Dacron, under the chemical name PET (polyethylene terephthalate), suitable.

In the following, preferred embodiments of the occlusion device according to the invention are explained in more detail with reference to drawings. The features mentioned in the claims and in the description can each be used individually or in any combination. Show it:

1 a lateral sectional view of the left atrium followed by a cardiac ear for the first basic form of the auricle (Collar);

2 the second basic form of a cardiac ear (funnel-shaped);

3 a third basic form of the atrial appendage (tubular);

4 possible morphologies of the Herzohreinganges in plan view;

5 an occlusion device according to the invention for closing the atrial appendage in the first basic form in front and top view;

6 a nitinol tube with subsequent laser processing and heat treatment for the production of the occlusion device 5 in two side views;

7 an occlusion device according to the invention in the implanted state for the first basic form of the atrial ear as a lateral sectional view;

8th another occlusion device according to the invention for closing a cardiac ear according to the second basic form in front and top view;

9 another occlusion device according to the invention for closing a cardiac ear according to the third basic form in front and top view;

10 another occlusion device according to the invention for closing a cardiac ear adapted according to the first basic form in front and top view;

11a A further occlusion device according to the invention in a top view, in another plan view rotated by 90 °, in a side view and in another side view rotated by 90 °;

12a C shows another Occlusionsinstrument invention in two rotated by 90 ° to each other side views of the function of a hinge joint and a detailed view and

13a , b another Occlusionsinstrument invention with a partial section for showing a coupling element and a detailed view of the coupling element.

In the 1 to 3 are possible basic types of heart ears 3 (collar, funnel-shaped and tubular) as a lateral section with different ratios of the diameter 5 of the auricular entrance 4 to the diameters 6 in the heart ear 3 shown. 4 shows possible morphologies of the atrial appendage 4 in the left atrium 2 in plan view 1 is the diameter 5 of the auricular entrance 4 smaller than the largest diameter 6 in the heart ear 3 , For this application is an occlusion device 1 to 5 suitable. The occlusion device 1 to 5 includes a grid-shaped support structure 16 (eg with cut out parallelograms for good foldability within the catheter) with an opening 19 at the distal end 12 , a proximal end 10 , a proximal retention area 11 , a distal end 12 and a distal retention area 13 , Such an occlusion device 1 will be in a lock 29 (please refer 7 ) via an insertion wire 30 which is about the clutch 20 (please refer 5 ) with the occlusion device 1 connected to the heart ear 3 placed. After a previous transseptal puncture, the sluice becomes 29 with the mouth in the bottom of the auricle 3 submitted. By moving the in the lock 29 located insertion wire 30 in the axial direction, which via the coupling 20 with the occlusion device 1 becomes the occlusion device 1 gradually out of the mouth of the lock 29 pushed so that the occlusion device 1 equally gradually can deform back into its original state; while the occlusion device fits 1 in length exactly the conditions of the heart ear 3 at. This is possible in particular because of membrane 14 and 15 with a support structure 9 parallel to the longitudinal axis of the occlusion device 1 running elements by a slight back pressure in the Occlusionsinstrument 1 move in such a way that a cover 23 (please refer 5 ) fit the Herzohreingang 22 can close.

The exemplary occlusion device 1 (please refer 5 ) points in the middle region of its length 18 or in the area 21 the largest diameter of the occlusion device 1 a certain number of hook elements 17 which spread evenly on the circumference and cause the occlusion device 1 stuck in the heart ear 3 can be anchored.

The secure closure of the atrial ear 3 is further ensured by the fact that the lid 23 (please refer 5 ) outside the heart ear 3 in the transition to the left atrium 2 located. Because the lid 23 is circular and its diameter is at least as large as the large diameter of the elliptical Herzohreinganges the Herzohreingang 4 completely covered (see 7 ). The sealing of the blood stream can be done by a correspondingly large fleece (PET), which covers the entire lid 23 covered.

According to the circular design of the lid 23 reproduces the elliptical shape of the atrial appendage 4 no longer important, since (as already described) the diameter of the lid 23 is at least as large as the large diameter of the ellipse 31 ,

The production of occlusion devices according to 6 will be described below.

The other occlusion instruments according to the invention 1 to 8th and 9 do not differ in function from the occlusion device according to the invention 1 to 5 , but only in the form of the middle part for the 2nd type of heart tube (funnel-shaped) 8th and the different shape range for the 3rd type of heart tube (tubular) 9 , Same elements were analogous to 5 provided with the same reference numerals.

Another occlusion device according to the invention 1 arises after 10 in that the area below the membranes 14 and 15 to the proximal end 10 is formed out oval. This allows for appropriately shaped heart ears 3 an occlusion device according to the invention 1 lidless 23 , Such an occlusion device 1 can with appropriate shaping of Occlusionsinstrumentmittenbereiche (funnel-shaped) and (tubular) with respect to the front views after 8th and 9 and elliptical after the top view of 10 basically ensure the closure of the different types of cardiac ear already described; however, it must be ensured that the elliptical shape of the occlusion device 1 exactly the elliptical shape of the Herzohreinganges 4 equivalent.

For all occlusion devices according to the invention 5 . 8th .

9 and 10 result in analogous shaping manufacturing processes. So be after 6 from a nitinol tube 24 First of all, parts of the material have to be separated out correctly. Then the lasered Nitinolrohr 24 expanded and by heat treatment in the form 25 brought. By repeating the steps lasers and heat treatment including shaping, the further process steps result 26 . 27 and 28 and until after 6 the desired shape (for example, after 5 ) is achieved. Such process steps can be repeated up to ten times and more. The temperature ranges include about 300 to 600 ° C at a residence time of the blank between 2 to 20 minutes.

The table inserted below shows exemplary sizes of the occlusion device or occluder according to the invention: size Herzohreingang ⌀ [mm] Occluder ⌀ D1 [mm] Occluder compressed ⌀ D1 [mm] Length L1 [mm] Length compressed L1 [mm] 01 10.0 to 12.0 15.0 13.4 + 0.2 13.6 11.3 02 12.1 to 13.5 18.0 16.1 + 0.2 16.3 13.5 03 13.6 to 15.5 20.0 17.9 + 0.3 18.1 15.0 04 15.6 to 17.5 23.0 20.6 + 0.3 20.8 17.3 05 17.6 to 19.5 26.0 23.2 + 0.4 23.6 19.5 06 19.6 to 21.5 29.0 25.9 + 0.4 26.3 21.8 07 21.6 to 26.5 32.0 28.5 + 0.5 29.0 24.0

The third column indicates the diameters of the different occlusion instruments in the initial state before implantation, the fourth column indicates the corresponding diameters of the different occlusion instruments in the compressed state after implantation, the fifth column indicates the lengths of the different occlusion instruments in the initial state before implantation, and the sixth column indicates the corresponding lengths of the occlusion devices in the compressed state after implantation. The latter value is a maximum value that can not be exceeded, but can not be achieved.

The 11 shows the occlusion device in two mutually rotated by 90 ° side views ( 11a and 11b ) and in the corresponding two plan views ( 11c and 11d ). The occlusion device has a proximal end 10 with the flat lid 23 , a distal end 12 with the lip 7 , a movable hinge area therebetween and a lasered support structure 18 on.

As in the 11c and 11d shown, point the lid 23 and the hinge region usually has a circular cross-section. The lip 7 is in the 11a to 11d shown in a light shade of gray. The lip 7 usually has no circular, but an oval or elliptical or flattened cross-section. The lip 7 is not rotationally symmetric. Upon completion of implantation, the flat side of the lip becomes 7 abut the heart ear. With "flat" side of the lip 7 is parallel to the major axis of the imaginary ellipse of the cross-section of the lip 7 meant. By the concern of the flat side of the lip 7 at the heart ear 3 becomes a harmful bulge of the heart ear 3 avoided.

The lip 7 tapers towards the distal end 12 in the transition to the joint area on its mostly circular shape. The circular shape achieves self-centering, ie an effect that the occlusion device has 1 at the conclusion of the implantation rotates in the situation described above, in which a harmful bulging of the auricle 3 is avoided.

The 12 and 12b show, analogous to the 11a and 11b , two side views of the occlusion device rotated 90 ° to each other 1 , In 12b the significant mobility of the joint area is clarified. As in 12c shown, the mobility of the joint area z. B. can be achieved by a lasered structure of longitudinal web elements.

In the 11 and 12 are fastening hooks 17 shown in a hook area 18 or are arranged in the joint area. The fastening hooks 17 can with a stronger expression in the direction of the lid 23 can be arranged, ie in this direction, the fastening hooks 17 in greater numbers, length, thickness, strength, etc. occur. By a sufficient number of mounting hooks 17 can despite a small length of the hooks 17 on the one hand the proper anchoring of the occlusion device in the range of approx. 1 mm 1 be secured on the other hand, it can be prevented that can lead to perforations of the pericardium. The fastening hooks 17 can be made by lasers by the web elements of the support structure 16 cut by using a laser tool and then bent in the radial direction by 90 ° so that they can exercise a corresponding clamping function.

13a and b shows detailed views of a coupling element 20 of the occlusion device 1 at the proximal end 10 for connection to an insertion wire 30 for the implantation process. The coupling element 20 has a fastener, and is in the lid 23 sunk, leaving a smooth Surface is formed, which complicates a thrombus formation. The 11 . 12 and 13 further show exemplary arrangements of a patch 8th ,

LIST OF REFERENCE NUMBERS

1

Occlusion instrument (occluder)

2

Left atrium

3

Left ear of the heart

4

Atrial appendage input

5

Diameter of the Herzohreingang

6

Largest diameter in the auricle

7

lip

8th

patch

9

Supporting construction with parallel elements

10

Proximal end

11

Proximal retention area

12

Distal end

13

Distal retention area

14

Membrane 1

15

Membrane 2

16

support structure

17

hook element

18

Area hook element

19

Opening at the distal end

20

clutch

21

Area largest diameter of 1

22

Area Herzohreingang of 1

23

Cover (lid)

24

pipe

25

Processing level 1 of 24

26

Processing level 2 of 24

27

Processing level 3 of 24

28

Processing level 4 of 24

29

lock

30

insertion wire

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

• EP 1852141 A2 [0004]
• WO 2007/140797 A1 [0007]
• DE 102005053906 A1 [0007]
• WO 2008/125689 A1 [0007]

Claims (10)

Occlusion instrument ( 1 ) for closing a cardiac ear ( 3 ), comprising - a first portion at a proximal end ( 10 ) of the occlusion device ( 1 ) attached to the diameter ( 5 ) of a Herzohreingangs ₍ 4 ₎ , and - a second section corresponding to the length of the atrial appendage ( 3 ), the occlusion of the atrial appendage ( 3 ) by the occlusion device ( 1 ) is reached by passing through two in the second section at a distal end ( 12 ) of the occlusion device ( 1 ) superimposed membrane ( 14 . 15 ) the occlusion device ( 1 ) is correctable in length. Occlusion instrument ( 1 ) according to claim 1, wherein the first portion has a cross-section which corresponds to the cross section of the Herzohreinganges ₍ 4 _{) is} adjusted. Occlusion instrument ( 1 ) according to claim 1 or 2, wherein it further comprises a lid ( 23 ) at the proximal end ( 10 ) of the occlusion device ( 1 ). Occlusion instrument ( 1 ) according to claim 3, wherein the first section adjoins the lid ( 23 ) with respect to the lid ( 23 ) a diameter reduction adapted to the diameter ( 5 ) of the Herzohreingangs ( 4 ) having. Occlusion instrument ( 1 ) according to one of the preceding claims, wherein the second section adjoins the first section an increase in diameter adapted to the diameter ( 6 ) of the auricular heart ( 3 ) having. Occlusion instrument ( 1 ) according to one of the preceding claims, wherein a proximal retention area ( 11 ) of the second section to the distal end ( 12 ) tapers funnel-shaped. Occlusion instrument ( 1 ) according to one of the preceding claims 1 to 5, wherein a proximal retention area ( 11 ) of the second section to the distal end ( 12 ) is formed cylindrically. Occlusion instrument ( 1 ) according to one of the preceding claims, wherein it further comprises at least one coupling ( 20 ). Occlusion instrument ( 1 ) according to one of the preceding claims, wherein it further comprises at least one hook element ( 17 ). Method for producing an occlusion device ( 1 ), comprising the following steps: - separating material parts from a tube ( 24 ), - expansion of the tube ( 24 ), - shapes of the pipe ( 24 ) by a heat treatment, if necessary repeating all or some of the above steps, until the occlusion device ( 1 ) has a shape according to one of the preceding claims.

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