LVADs are designed to take over the function of the weakened heart's left ventricle, which delivers oxygenated blood from the heart to the body. The device, which is implanted in the patient's chest, consists of an electric motor and a driveline. A tube placed in the left ventricle diverts blood from the heart to the pump. The motion of the pump then propels the blood back into the aorta—with enough force to be distributed adequately throughout the body.
The pumps used in LVADs can be divided into two main categories: pulsatile and continuous-flow. The HeartMate II, pictured to the right, is a continuous-flow device. In addition to extending the life of the patient's own heart, the improved blood flow to the body allows patients to breathe easier and experience less fatigue. Since the LVAD system is relatively easy to use, patients can leave the hospital setting with the implanted device and return to the activities of normal life.