Abstract
Implantation of prosthetic heart valves requires open heart surgery. Recently, two new artificial heart valves have been developed for implantation by a transluminal catheter technique without using thoracotomy or extracorporal circulation. A balloon-expandable, biological stent valve was developed in Europe and implanted in 70–80 kg pigs. Implantation was performed in the descending thoracic aorta (n=6), in the ascending aorta (n=5), and in the left ventricular outflow tract (n=4). A mechanical cage-ball, self-expandable stent valve was developed in the USA and implanted in 21–27 kg dogs in the left ventricular outflow tract (n=12). Acute hemodynamic and angiographic studies showed that catheter implantation of artificial heart valves is feasible and the valves were competent. Complications were related to partial restriction of coronary flow caused by the biological valve, and embolization of parts of the mechanical valve. However, these early experimental studies indicate that the development of a biological and a mechanical-prosthetic aortic valve for transcatheter placement is feasible.
