Background: Congestive heart failure is a pervasive disease afflicting millions of people. For many, their quality of life can be significantly improved by a pericardial device that can enhance cardiac output without the added risk of thromboembolism associated with direct blood contact.
Methods: A cardiac assist device with tubular elements is wrapped around the heart. Fluid is pumped into and out of the wrap causing contraction and dilation of its circumference. This contracting and relaxing action generates cardiac assistance without the need to contact blood. In vitro characterization and in vivo studies in calves were conducted to demonstrate the characteristics of the device.
Results: In vitro characterization with the device wrapped around one-half of a ventricle to simulate left ventricular support demonstrated outputs of 6.5 L/min at physiological afterloads. In vivo studies in calves demonstrated both cardiac output and afterload enhancements when the device is activated.
Conclusions: This study provides a first demonstration of a device that provides cardiac support by a contraction and relaxation scheme with the device wrapped around the epicardium of the heart. The main feature of this actuation method is the potential for building a small device for implantation without blood contact.