Review of devices and clinical need for non-blood contacting mechanical circulatory support

LVADs have been in clinical use for a half-century and have advanced through at least 3 generations resulting in compact, durable, and powerful pumps that can deliver blood flow that exceeds the needs of the body at rest. In so doing, these devices have become the best alternative to transplant for patients with end-stage heart failure. That said, the blood contacting interface of these pumps is likely the cause of complications and contraindications that persist with successive generations. Patients with elevated risk for side effects or patients with biventricular failure and other conditions represent the 25% of patients that are not candidates for LVAD therapy. Such patients represent the clinical need for non-blood contacting mechanical circulatory support. The clinical use of direct cardiac compression devices is limited, and there are no devices available for human use. Technological challenges remain, yet these devices continue to be developed and tested in animal models of heart failure.