Mechanical Circulatory Support for Biventricular Heart Failure Using Continuous-Flow Total Artificial Heart

Abstract

Purpose Biventricular assist device (BVAD) implantation is the treatment of choice in patients with severe biventricular heart failure (BHF) and cardiogenic shock . We previously developed a miniaturized continuous flow double-ended centrifugal pump intended for total artificial heart implant (CFTAH). The purpose of this initial in vitro study was to prove that scaled down CFTAH can be suitable for biventricular support. Methods The CFTAH was tested in BVAD configuration at 2 pump speeds (4500 and 6000 rpm) on a pulsatile mock loop with two pneumatic ventricles that simulated normal and heart failure conditions (moderate and severe) by adjusting the systolic and diastolic drive pressures to simulate hemodynamics of the failing biventricular function. Results The BVAD performance was maintained very well for both atrial and ventricular cannulation within the 4500 - 6000 rpm range. A stable hemodynamics were maintained, and the pump's self-regulating performance was confirmed with the most of atrial pressure difference (LAP-RAP) falling within ±5-15 mm Hg in (Mod.) and severe (Sev.) right (RHF) and left HF (LHF) conditions. Left and right pump flows (LPF and RPF) and total flow (TF) increased as the BVAD speed was increased (Figure). The TF was higher than LPF and RPF due to output from the native ventricles, and the LPF was higher than RPF with pump speed of 6,000 rpm, but the TF appeared balanced due to larger native right ventricular output vs. native left ventricle with given condition. Conclusion These initial in vitro study demonstrated that use of the CFTAH as BVAD supports cardiac output and arterial pressure in BHF conditions. In vivo evaluation of this technology is currently pending.