Hemodynamic and left ventricular pressure-volume responses to counterpulsation in mock circulation and acute large animal models.

Alternative therapies for treating heart failure patients are being explored to provide effective options for patients with progressive heart failure. Cardiac assist devices that promote myocardial recovery may be a potential solution. Ventricular assist devices (VAD) have demonstrated long-term efficacy and intraaortic balloon pumps (IABP) have shown short-term successes. In this paper, testing of a hybrid counterpulsation device (CPD) that couples the attributes of device longevity (VAD) with less invasive surgery (IABP) is presented. Hemodynamic and ventricular pressure-volume responses to a 40 ml CPD and 40 ml IABP were evaluated in vitro in an adult mock circulation and in vivo in a large animal heart failure model. The CPD is a flexing diaphragm ventricle with a controlled stroke volume up to 85 cc through a single, valveless cannula. In this study, the CPD was cannulated to the brachiocephalic artery to provide 40 ml of counterpulsation support. The CPD effectively provided diastolic augmentation increasing coronary flow and afterload reduction. These results were comparable to IABP. These preliminary studies suggest that CPD may be an effective therapy for treating patients with early stage heart failure.