Novel Bicuspid Aortic Valve Model with Aortic Regurgitation for Hemodynamics Analysis Using an Ex Vivo Simulator

Abstract Objective The objective was to design and evaluate a clinically relevant, novel ex vivo bicuspid aortic valve model that mimics the most common human phenotype with associated aortic regurgitation. Methods Three bovine aortic valves were mounted asymmetrically in a previously validated 3D-printed left heart simulator. The non-right commissure and the non-left commissure were both shifted slightly towards the left-right commissure, and the left and right coronary cusps were sewn together. The left-right commissure was then detached and re-implanted 10 mm lower than its native height. Free margin shortening was used for valve repair. Hemodynamics, high-speed videography, and echocardiography data were collected before and after the repair. Results The bicuspid aortic valve model was successfully produced and repaired. High-speed videography confirmed prolapse of the fused cusp of the baseline bicuspid aortic valve models in diastole. Hemodynamics and pressure data confirmed simulation of physiologic diseased conditions with aortic regurgitation and the subsequent success of repair. Regurgitant fraction post-repair was significantly reduced compared to that at baseline (28.6±3.4% versus 14.5±4.4%, p=.037). There was no change in peak velocity, peak gradient, or mean gradient across the valve pre- vs. post-repair: 292±18.3cm/s versus 325.3±58.2cm/s (p=.29), 34.3±4.2mmHg versus 43.3±15.4mmHg (p=.30), and 11±1mmHg versus 9.3±2.5 mmHg (p=.34), respectively. Conclusions An ex vivo bicuspid aortic valve model was successfully designed and recapitulated the most common human phenotype with aortic regurgitation. These valves were successfully repaired, confirming its potential for evaluating valve hemodynamics and optimizing surgical repair for bicuspid aortic valves.