Long-term left ventricular assist device support: a novel pump rate challenge exercise protocol to monitor native left ventricular function.

A novel, hemodynamically guided exercise protocol with two different left ventricular assist device settings in two long-term recipients is presented. This protocol allows for quantitation of the contribution of the native left ventricle to total cardiac output. It facilitates estimation of the risk associated with device dysfunction, as well as prediction of left ventricular recovery and the potential for weaning.