Platinum Metals Rev., 1969, 13, (4), 140
Iridium-Platinum in Heart Pacemaker
Prosthetic implants in the human body must be constructed from materials which resist the corrosive action of body fluids. Devices Implants Limited has developed a fixed-rate heart pacemaker suitable for either transvenous or transthoracic pacing. It rests in a subcutaneous pocket.
A logical solution to the corrosion problem has been to seal the electronic circuitry inside a welded metal can, which in turn is encapsulated in epoxy resin except for the passive metal plate forming the return electrode on the side of the pacemaker.
This plate, which obviously must remain inert during the useful life of the unit, is made of 10 per cent iridium-platinum alloy in the form of a in. diameter disc and is entirely unaffected by the corrosive environment of the body.
The tip of the catheter is also 10 per cent iridium-platinum and the active electrode at the tip is stainless steel.