IMPLANTABLE ATRIAL SEPTAL DEFECT OCCLUSION DEVICE WITH WOVEN CENTRAL SECTION ON LEFT ATRIAL FLANGE

Abstract

The present invention relates to a device (D) for occluding atrial septal defect. Non-woven wires are introduced in one or more stages, with each stage interspaced with one or more braids and braided together with the wires from the woven centre and earlier stages to form the device (D). The transcatheter device (D) has two discs (101, 102) one a hub-less disc incorporating a woven central section on the left atrial side and the other disc on the right atrial side with a connecting neck (110) braided from wires. The device (D) has thrombogenic material in either discs (101, 102). A ridge (108) is configured on the periphery of either the left atrial disc or right atrial disc or both discs to improve structural stability of the device and provides enhanced elapsing force onto the septum reducing chances of migration.

Claims

1. An implantable atrial septal defect occlusion device (D) with woven central section on left atrial flange, the said device (D) comprising; two discs (101, 102), one a hub-less disc incorporating a woven central section on the left atrial side and the other disc configured on the right atrial side, with a connecting neck (110) braided from wires, the said discs consisting of thrombogenic material having a ridge (108), the said ridge disposed on the periphery of either the left atrial disc or the right atrial disc or both discs, wherein, non-woven wires are configured in one or more stages, with each stage interspaced with one or more braids and braided together with the wires from the woven centre and earlier stages to form the device (D).

2. The device (D) as claimed in claim 1, wherein a ridge is configured on the periphery of either the LA flange or the RA flange or both flanges to improve the structural stability of the device and provides enhanced clasping force onto the septum reducing chances of migration wherein the said peripheral ridge gives a softer edge for the device reducing atrial wall erosion.

3. The device (D) as claimed in claim 1, wherein the said device having no hub and a flat central section on the left atrial disc occupying lesser volume inside the left atrium and improved endothelialization.

4. The device (D) as claimed in claim 1, wherein the braid is a regular braid and the central weave is a plain weave or a twill weave.

5. The device (D) as claimed in claim 1, wherein the distal end where the wire ends meet (109) are combined together in a hub incorporating the release mechanism.

Description

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0014] FIG. 1 shows an embodiment of the invention showing RA side and a portion of LA side with the free ends of the wires inserted into a hub on the RA side.

[0015] FIG. 2(a) shows the representation of the twill weave which is done using the first fraction of the wires forming the device.

[0016] FIG. 2(b) shows arrangement of wires in the weave with corners opened.

[0017] FIG. 3 shows the pictorial representation of the LA side central section with the braids shown after the introduction of all the wires in three stages.

[0018] FIG. 4 shows the side view of the device showing the LA and RA sides and the neck region connecting the two discs.

[0019] FIG. 5 shows the isometric view of the invention showing ridge on the LA flange.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0020] The invention which is a device for occluding atrial septal defect is disclosed here.

[0021] A transcathether device for use as an atrial septal defect occluder has two discs, one a hub-less disc incorporating a woven central section on the left atrial side and the other disc on the right atrial side with a connecting neck braided from wires and the device has thrombogenic material in either discs and the said neck with a ridge along the periphery of either the left atrial disc or the right atrial disc or both discs.

[0022] Wires are braided and shaped into a two lobed structure and heat set into the required shape. Metal alloys such as Nitinol can be used to braid the device and shaped as is well known in the art. The braided structure has a closed end which forms the LA flange (101) of the device thus avoiding a hub and ensuring that minimum volume is occupied in the left atrium. The device having no hub and a flat central section on the left atrial disc occupying lesser volume inside the left atrium and results in improved endothelialization.

[0023] The closing of the LA flange has been achieved in the prior art either by (i) criss-crossing all the wires across the centre or (ii) criss-crossing only a part while looping back the remaining part in a particular pattern.

[0024] The method discussed here uses a novel combination of weaving the wires to form a mat like central section with one part of the wires, and then introducing the other parts in either a single stage or multiple stages, introducing them as loops. Looped wires are introduced in one or more stages, with each stage interspaced with one or more braids, and braided together with the wires from the woven centre and earlier stages to form the device. The next stages are introduced after one or more braids of the existing wires and finally all strands are braided together. The braid is a regular braid where as the weave could be regular or a twill weave, (105). The final braid could incorporate either a regular braid or a diamond braid.

[0025] The woven wires are introduced onto a mandrel which holds the weave in place and the open ends are braided. Then the next stages of wires are added as loops, (104) after the formation of the braid between the woven wires. The newly introduced wires are braided with the existing braids forming a single braid; after two sets of braiding the final set of wires are added and braided on a suitable mandrel with closed end as visible in FIG. 5.

[0026] The second (104) and third (105) stages of wires are introduced onto the stubs on the mandrel which initially holds them in place before being braided onto the mandrel.

[0027] The wire mesh, (103) is formed with the weave mat (106) on the top and the wires introduced in subsequent stages (104 & 105), all getting braided together. The wire mesh is shaped into the required device shape of two flange structure with a connecting neck (110).

[0028] The weave design on the end results in the formation of a flat (107) end which helps in reducing the volume occupied by the device in the atrium. The hub-less flange can facilitate a continuous endothelium formation on top of the device. The metal mesh will be shaped into the twin-disc frame form and heat set; a material with thrombogenic properties, such as non-woven thin fabrics, is inserted into the twin discs and the neck region to induce closure of the atrial septal defect when the device is deployed in it.

[0029] The distal end where the wire ends (109) are combined together in a hub incorporating the release mechanism.

[0030] Further, a ridge (108) can be introduced on the periphery of either the LA flange or the RA flange, or both flanges to improve the structural stability of the device and provides enhanced clasping force onto the septum reducing chances of migration. The peripheral ridge gives a softer edge for the device reducing chances of atrial roof erosion.