Preliminary in vitro evaluation of the first neonatal total artificial heart

A neonatal total artificial heart (TAH), used as a bridging device, can offer circulatory support for patients suffering from otherwise insupportable and inoperable congenital cardiac defects. The choice of the 7.0 ml stroke volume (SV) was based on reported studies on cardiac output (CO) requirements and maximum dimensions of a neonate size TAH. This SV will allow a bridging period of up to 10 weeks in the growing neonate. For in vitro testing purposes, "high-profile" ball valves of in-house design (10-13 mm ID) were used. Redesign of the existing in vitro testing systems, including mock circulation and high-flow blood reservoirs, was required for the smaller device. Mock circulation studies (rates 90-160 BPM, full-fill and ejection modes) showed adequate device performance, with CO values well above the reported marginal output value of 139 ml/kg/min.