Hemolysis in an electromechanical driven pulsatile total artificial heart.

A motor rotation in an electromechanically-driven pulsatile total artificial heart (TAH) may influence hemolysis. This study is designed to evaluate motor rotational conditions of the TAH and choose a suitable condition to obtain the least hemolytic characteristics. The TAH was driven in two motor rotational conditions: a constant motor rotational speed (rpm) mode (mode A) and a gradually increasing rpm mode (mode B). In these two modes, a maximum dP/dt value and a degree of hemolysis were measured and compared. The TAH was connected to an in vitro testing loop. In each mode, the TAH was driven with a fixed pumping rate of 100 bpm. A preload and an afterload were held at 15 and 100 mm Hg, respectively. The outflow of the TAH was maintained at 4.0 L/min. The maximum dP/dt in mode A and mode B was 5914 +/- 405 mm Hg/s and 2953 +/- 191 mm Hg/s, respectively. The NIH value obtained from mode A and mode B was 0.063 +/- 0.005 g/100 L and 0.026 +/- 0.003 g/100 L, respectively. The results demonstrated that the TAH driven in a gradually increasing rpm mode reduces both a maximum dP/dt value and a degree of hemolysis. The gradually increasing rpm mode is a suitable driving condition to obtain the least hemolytic characteristics.