An annular compliance chamber for the Pennsylvania State University electric total artificial heart.

To eliminate the need for a separate parapleural compliance chamber, we are currently investigating the feasibility of an annular compliance chamber. This chamber wraps around the energy converter and fits between the blood pumps of the Pennsylvania State University electric total artificial heart. For the 100 cc total artificial heart, the compliance chamber volume is 76 ml and the tissue contacting surface area is approximately 85 cm2. The chamber is made of Dacron velour covered segmented polyether polyurethane urea. The annular compliance chamber was evaluated in vitro by comparing pump balance control performance against that obtained with an open vent. In the CVP range of 5-12 mmHg, LAP was maintained within 1 mmHg of the values obtained with a vent. Studies continue to determine the range of volumes over which the chamber is effective, differences in rates of diffusion, and performance during changes in barometric pressure.