Hydrodynamic Characteristics of Bovine Pericardial and Porcine Valves Using a Mock Circulatory System Mimicking the Aortic and Pulmonary Positions

Abstract

Purpose: Aortic prostheses are used in pulmonary positions due to structural similarities between the pulmonary and aortic valves. However, there are no available studies that have comprehensively evaluated the mechanism of bioprosthetic aortic valves under pulmonary conditions. Materials and Methods: Using a mock circulatory system, we evaluated the hydrodynamic characteristics of bovine pericardial and porcine valves. Geometric orifice area, regurgitant and leakage volume, regurgitant fraction, peak pressure gradient, and forward flow volume were evaluated in different pulmonary pressure conditions (from 15/5 mm Hg to 75/35 mm Hg) and normal aortic pressure (110/80 mm Hg). Results: Bovine pericardial valves were associated with larger opening area (0.93 +/- 0.01 vs.1.70 +/- 0.01 for 23-mm valve; 0.99 +/- 0.01 vs.1.75 +/- 0.01 for 25-mm valve; 1.58 +/- 0.01 vs. 2.25 +/- 0.02 for 27-mm valve; all p<0.01) and forward flow volume (42.27 +/- 0.05 vs. 64.79 +/- 0.14 for 23-mm valve; 46.41 +/- 0.06 vs. 64.28 +/- 0.18 for 25-mm valve; 72.64 +/- 0.17 vs.73.25 +/- 0.07 for 27-mm valve; all p<0.01). Porcine valves were associated with incomplete opening, smaller opening area, and lower regurgitant fraction. Bovine pericardial valves demonstrated lower peak pressure gradients (15.75 +/- 0.14 vs. 12.57 +/- 0.47 for 23-mm valve; 14.85 +/- 0.05 vs. 12.87 +/- 0.28 for 25-mm valve; 15.72 +/- 0.32 vs. 7.91 +/- 0.03 for 27-mm valve). Conclusion: Bovine pericardial and porcine bioprosthetic valves has different hydrodynamic characteristics under various pulmonary pressure conditions.