The heart is a beating muscle that pumps blood to the lungs and body through the circulatory system. Inside the heart are four chambers that are responsible for collecting blood and then redistributing it to the body. The top two chambers are called the right and left atria, and the larger chambers on the bottom are called the right and left ventricles. The left ventricle is responsible for pumping 3 to 6 liters of blood to the entire body every minute. However, disease can sometimes cause failure of the left ventricle to pump enough blood to keep the body functioning normally. In this case, a machine called a left ventricular assist device, or LVAD, can help the heart perform its work. A left ventricular assist device is a mechanical pump-type apparatus that is surgically implanted in the body. It helps maintain the pumping ability of a heart that cannot effectively work on its own. Many of the new LVADs are implanted directly into the left ventricle and propel blood through a tube that is attached to the aorta. In this way the LVAD decreases the amount of work the impaired heart needs to perform. Left ventricular assist devices are especially beneficial to patients awaiting heart transplants. Because the need for hearts far outweighs the number of hearts available for donation, a left ventricular assist device can be a true life-saver. There are several potential complications associated with this procedure that should be discussed with a doctor prior to surgery.