Stentless bioprostheses

TAVI within failing surgical aortic bioprostheses

Designed to achieve a more physiological flow pattern and superior haemodynamics in comparison to stented valves, stentless valve bioprostheses are composed of either porcine (xenograft) or human (homograft) aortic root tissue, lack a rigid scaffold and have no radiopaque components. Limited radiolucency of stentless valves presents challenges requiring a variety of surgical implant techniques which offer advantages in certain indications such as depressed LV function. Recent studies suggest the preventive implantation of metallic vascular clips at the level of aortic annulus during the operation, in order to exist radiopaque landmarks, as a guide for a possible future TAV-in-SAV procedure, if tissue valves fail.