A Non-conventional Reniform Heart Valve Bioprosthesis with Improved Performance

Conventional bioprosthetic heart valves have been designed with circular mounting rings. This article describes a mitral bioprosthetic valve consisting of three bovine pericar-dial leaflets with a “reniform” base. Its shape resembles that of the mitral anulus, and therefore, it provides a better anatomic fit. Hydrodynamic comparisons were made between conventional valves (CV) and equivalent sized reniform valves (ERV) that would adapt to the same anulus. Under steady flow of 30 L/min, pressure drops were compared in CVs and ERVs. For CV sizes 27, 29, and 31mm, the ratios of pressure drops compared with ERVs were 2, 1.49, and 1.30, respectively. With the same flow rate, the ratios of effective orifice areas (EOA) for CVs and ERVs in sizes 27, 29, and 31mm were 1.41, 1.21, and 1.14, respectively. Under pulsatile flow (mean flow, 5 L/min, 100 beats/min [bpm]), the pressure drop across CVs was averaged for sizes 27, 29, and 31mm, and found to be 1.51-fold the averaged pressure drops for ERVs. In addition, ERV sizes 27, 29, and 31mm had EOAs averaging 1.24-fold those of CVs. Similarly, for an 80 bpm frequency, the pressure drops across CVs for the three sizes averaged 1.48-fold that of ERVs. The EOAs of ERVs were 1.22-fold those of CVs averaged for the three sizes.