Evaluation of cardiac beat synchronization control for a rotary blood pump on valvular regurgitation with a mathematical model.

We have studied the cardiac beat synchronization (CBS) control for a rotary blood pump (RBP) and revealed that it can promote pulsatility and reduce cardiac load. Besides, patients with LVAD support sometimes suffer from aortic and mitral regurgitation (AR and MR). A control method for the RBP should be validated in wider range of conditions to clarify its benefits and pitfalls prior to clinical application. In this study, we evaluated pulsatility and cardiac load reduction obtained with the CBS control on valvular failure conditions with a mathematical model. Diastolic assist could reduce cardiac load on the left ventricle by decreasing external work of the ventricle even in MR cases while it was not so effective in AR cases. Systolic assist can still promote pulsatility in AR and MR cases; however, aortic valve function should be carefully confirmed since pulse pressure can be wider not due to systolic assist but to AR.