Transcatheter Aortic Valve Implantation for High-risk Patients with Severe Aortic Stenosis

Abstract

Since the first successful valve replacement using the caged-ball valve, numerous engineering modifications have been made to enhance hemodynamic performance and durability of the artificial valve. Currently, various types of artificial valves are available are implemented depending on patient characteristics and need for surgical valve replacement. Bioprosthesis has the advantage of a low thromboembolism rate without warfarin, however, structural valve deterioration is a disadvantage. On the other hand, a mechanical valve has superior durability compared to the bioprosthesis. However, mechanical valve use requires life-long anticoagulant therapy. Recently a catheter-delivery heart valve, classified as a bio-prosthesis, has been implanted in patients outside Japan.