Abstract
BACKGROUND: This study compares short-term clinical and hemodynamic outcomes of AVR using mechanical versus bovine pericardial valves in patients with a small aortic annulus (≤ 21 mm) and evaluates the feasibility and safety of AVR in this population. METHODS: Between November 2020 and November 2022, 142 patients with a small aortic valve annulus underwent AVR at Wuhan Asia Heart Hospital, with 73 patients in mechanical group and 69 in biological group. All patients met the surgical criteria for AVR. Baseline data, historical diseases, preoperative and follow-up echocardiographic results, and surgical-related data were shown in this study. RESULTS: All patients successfully underwent surgery. In the mechanical valve group, four perioperative deaths occurred due to multiple organ failure, respiratory and cardiac arrest and circulatory failure. After one-year follow-up, hemodynamic parameters improved in both groups compared with preoperative values. Although the mechanical valve group demonstrated lower peak pressure gradients and maximum velocity compared with the bioprosthetic valve group in the follow-up period (P < 0.05), the bioprosthetic valve group exhibited shorter Intensive Care Unit (ICU) stay(3.6 ± 2.5d vs. 5.3 ± 7.9d, P < 0.001 ) and cardiopulmonary bypass (CPB) times (178.1 ± 89.0 min vs. 192.4 ± 124.3 min, P = 0.032), and fewer postoperative complications at the one-year follow-up (4.3% vs. 14.9%, P = 0.026). No cerebrovascular events, valve dysfunction, or structural valve degeneration were observed in either group during the follow-up period. CONCLUSIONS: Both mechanical and bioprosthetic valves showed excellent short-term outcomes in small aortic annulus patients. Bioprosthetic valves were comparable to mechanical valves, with potential benefits in reducing ICU stay, CPB time, and complications. For elderly patients, bioprosthetic valves are a safe and effective alternative in small aortic annulus AVR.