Leaflet Material Selection for Aortic Valve Repair

Abstract

Leaflet replacement in aortic valve repair (AVr) is associated with increased long-term repair failure. Hemodynamic performance and mechanical stress levels were investigated after porcine AVr with 5 types of clinically relevant replacement materials to ascertain which material(s) would be best suited for repair. Porcine aortic roots with intact aortic valves were placed in a left-heart simulator mounted with a high-speed camera for baseline valve assessment. Then, the non-coronary leaflet was excised and replaced with autologous porcine pericardium (APP), glutaraldehyde-fixed bovine pericardial patch (BPP; Synovis™), extracellular matrix scaffold (CorMatrix™), or collagen-impregnated Dacron (HEMASHIELD™). Hemodynamic parameters were measured over a range of cardiac outputs (2.5–6.5L/min) post-repair. Material properties of the above materials along with St. Jude Medical™ Pericardial Patch with EnCapTM Technology (SJM) were determined using pressurization experiments. Finite element models of the aortic valve and root complex were then constructed to verify the hemodynamic characteristics and determine leaflet stress levels. This study demonstrates that APP and SJM have the closest profiles to normal aortic valves; therefore, use of either replacement material may be best suited. Increased stresses found in BPP, HEMASHIELD™, and CorMatrix™ groups may be associated with late repair failure.