Catch member for PFO occluder
Delivery (and recovery) devices and techniques for delivering an implant into a desired location within the body and catch systems for such implants. The devices and techniques relate particularly to, but are not limited to, a patent foramen ovale (PFO) occluder made from a polymer tube. A catch system maintains an occluder in a deployed configuration by holding it in a reduced axial length position. Some embodiments have a compressible tip. Some embodiments have temporary catching mechanisms.
1. A collapsible medical device for occluding an aperture in a body, the medical device having a first configuration as a reduced profile and a second configuration as an expanded profile, the medical device being adapted to be delivered through a delivery system into a desired delivery location, the medical device comprising:
an occluder portion movable between the first and the second configuration, wherein the occluder portion comprises a proximal end, a distal end, and an axial passage between the proximal end and the distal end, the axial passage having an inner diameter:
a catch member adapted to be disposed in the axial passage of the occluder portion, wherein the catch member comprises a catch body having a proximal portion and a distal flange,
wherein the distal flange of the catch member engages the distal end of the occluder portion,
wherein the catch body has a tapered or graduated cylindrical profile composed of a distal section having a first diameter D 1 and a proximal section having a second diameter D 2 joined by a sloped section, wherein diameter D 2 is similar to the inner diameter of the axial passage of the occlude portion; and,
wherein the proximal portion of the catch body of the catch member further comprises two compressible prongs each comprising a proximal tip and a proximal ridge on the surface of the prong, wherein the proximal tip is adapted for connection to a delivery system; and the proximal ridge is adapted to pass through the axial passage of the occluder portion while the compressible prongs are held in a compressed position and to engage the proximal end of the occluder portion thereby holding the medical device in the second configuration.
2. The medical device recited in claim 1 , wherein the catch member is made of polymeric material.
3. The medical device recited in claim 1 , wherein the prongs extend more than one third of the distance of the catch body.
4. The medical device recited in claim 1 , wherein the proximal ridge on the catch body has a stepped profile above the surface of the catch body.
5. The medical device recited in claim 4 , wherein the space between the prongs is about one third of the diameter of the catch body.
6. The medical device recited in claim 1 , wherein the catch body is so dimensioned that the catch body and the passage have a friction fit.