Implant delivery system and method of use

1. An implant delivery system, comprising:

a catheter having a delivery lumen;

a pusher member slidably disposed in the catheter delivery lumen;

an expandable implant carried on a distal end portion of the pusher member;

a plurality of retention members, each having a first end attached to the pusher member at a location distal to the implant, and a second end releasably engaging the implant to thereby retain the implant in a collapsed configuration on the pusher member for delivery of the implant through the catheter delivery lumen; wherein the respective first ends of the retention members are pivotally attached to the pusher member; and

an inflatable membrane attached to the pusher member and having an exterior surface affixed to the respective retention members, the pusher member comprising an inflation lumen in communication with an interior region defined by the membrane, wherein inflation of the membrane causes the retaining members to disengage the implant and thereby allow the implant to expand from the collapsed configuration,

the implant delivery system further comprising a guidewire disposed within the inflation lumen of the pusher member.

2. The system of claim 1 , wherein the retention members are biased to retain the implant in the collapsed configuration on the pusher member.

3. The system of claim 1 , the pusher member comprising a stop member proximally disposed to the expandable implant carried on the pusher member, wherein the stop member limits translation movement of the implant when the implant is in the collapsed configuration.

4. The system of claim 3 , wherein the stop member comprises an annular ring or a plurality of protrusions disposed on the pusher member.

5. The system of claim 1 , further comprising a seal member disposed distally to the inflatable membrane of the pusher member, the seal member having an opening to allow passage of the guidewire.