A ventricular assist device (VAD) is a mechanical pump that supports heart function and blood flow in people who have weakened hearts. These devices can support the function of the left, right, or both heart ventricles. Ventricles are the lower chambers of your heart. The VAD includes tubes to carry blood out of your heart and to your blood vessels, a power source, and a control unit to monitor device function. The device may be used to support your heart until it recovers, to support your heart while you are waiting for a heart transplant, or to help your heart work better if you are not eligible for a heart transplant.