Heart valve replacement, polyurethanes

Heart valve replacements are considered among the most widely used cardiovascular devices. Traditional choices to the replacement surgeries are the mechanical and bio-prostheses. However, there are risks doing the surgeries, including thrombosis, infection, and limited valve durability. In recent years advances in polymer science have led to an important and new class of artificial heart valves made up of polyurethane-based... 

Future prospective of polyurethane heart valve replacement... 

Polyurethanes Ligament replacements, heart valve prostheses, vascular graft prostheses, breast prosthesis, catheter, cannulae films, tubing... 

The artificial heart, Jarvik-7, which has been successful in keeping a recipient alive for more than a year, has valves made from modified polypropylene and the two ventricles made of polyurethane supported on an aluminum base. For arterial replacements or bypass of clogged blood vessels, polyester fiber such as Du Font s Dacron remains the preferred material. 

Biolized materials have been used in our cardiac prostheses since 1969. The first application utilized glutaraldehyde treated bovine aortic valves in a Dacron fabric pump termed a "partially biolized heart". Since thick pseudoneointima (PNI) formation and calcification was observed, the Dacron covered surface was replaced with natural tissue material (9). This original totally biolized heart was a sac-type with a flexing element of natural rubber lined on the blood side with aldehyde treated bovine pericardium. The outside case of the device was made from polyurethane. Early in 1973, a calf implanted with this artificial heart lived for a then-remarkable seventeen days (10). Termination of the experiment was caused by a crack in the flexing sac. A passive implant of this device in the aorta did not show any thrombus formation during 5.5 years implantation. 

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