Control of rotary heart assist devices

Rotary assist devices are state of the art blood pumps that are used in therapies to treat weak hearts, usually associated with myocardial diseases. We develop three indices to detect the occurrence of suction in these pumps: pulsatility index, diminishing returns index and harmonic index. Experimental studies in calves show that these indices can detect suction at approximately the same speed. Control of ventricular assist devices based only on suction detection may not satisfy other requirements for some hemodynamic variables. A multi-objective optimization scheme has been developed to consider other hemodynamic variables. We demonstrate the feasibility of this approach using a Physbe simulation of AOP and LAP. A non-inferior set of pump speeds was found that includes speeds that optimize performance with respect to these two variables.