Pediatric continuous-flow total artificial heart with rotor axial position tracking technology: First report of in vivo assessment

Abstract

Background: The pediatric continuous-flow total artificial heart (P-CFTAH) is a novel double-ended centrifugal pump designed with the intent to provide circulatory support for pediatric heart failure. To enable continuous monitoring of pump hemodynamics, Hall effect sensors (HES) were embedded inside the P-CFTAH design to track both axial movement and position of the pump rotor postimplantation. Herein, we report an early in vivo evaluation of the P-CFTAH with HES, implanted in small-sized ovine models. Methods: Five healthy lambs were used for the P-CFTAH implantation via a full median sternotomy and cardiopulmonary bypass support. Successful evaluation of the P-CFTAH was achieved in 4 out of 5 (n = 4, 20.9 ± 1.3 kg). The hemodynamics and operating conditions were continuously recorded with varying pump speeds (2,800-5,000 rpm), systemic/pulmonary vascular resistance ratio, and high- and low-volume conditions. Among the 4 cases, P-CFTAH with HES embedded in the rotor was used in 2 cases. Results: All surgical procedures were uneventful, and the optimal anatomical fit of the pump was shown in the chest. Differences between the left and right atrial pressures were mostly maintained within the intended limit of ±10 mm Hg throughout the design range of systemic and pulmonary vascular resistance. The HES accurately traced the rotor position, showing a positive correlation with atrial pressure differences. Conclusions: The findings suggest that the P-CFTAH has the potential to provide self-balancing circulatory support for pediatric heart failure patients. The study contributes to the development of a pediatric-sized total artificial heart with improved monitoring.

Keywords

• pediatric heart failure
• congenital heart disease
• mechanical circulatory support
• pediatric total artificial heart
• large animal study