Controllable barbed intracardial electrode

Claim 1

A controllable repeatably implantable electrode comprising a conducting head, a conductor electrically connected to said head, said head having a front portion and elongated body portion defining an axially oriented cavity, a tubular insulating member connected to said body portion and aligned with said cavity, said conductor being carried away from said head within said insulating member, a plurality of channels extending from said cavity through said front portion to the exterior of said head, and each disposed at an angle to the axis of said cavity, a rigid cylindrical piston movable axially within said cavity between a forward implantation position and a retracted position, carrying a plurality of resilient prongs each extending into a said channel, a removable force-transmitting member carried within said insulating member, having one end bearing against said piston and the other end remote from said piston, a flexible tension-transmitting member carried within said insulating member, having one end attached to said piston and the other end remote from said piston, said piston being moved within said cavity to said forward implantation position by force applied to said remote end of said force-transmitting member, said prongs being thereby moved through said channels to engage the heart tissue for implantation of said electrode, and said piston being moved to said retracted position by tension exerted on said remote end of said tension-transmitting member, said prongs being thereby retracted and freed from said heart tissue for removal of said electrode.