(DeBakey)
The left ventricular bypass is an air-driven pump that takes blood as it enters the heart's receiving chamber (the left atrium), shunting it through tubes past the left ventricle, and discharging it into the aorta for distribution to the rest of the body. The device can take some of the pumping load off the left ventricle, or it can take over all of its circulatory duties. Since the pump's stroke is synchronized from outside of the patient's body, it will maintain a proper rhythm even if his heartbeat should wobble or fail altogether. This pump is designed for temporary use, especially in patients whose hearts fail during or immediately after surgery.
After the ventricle has been rested and the heart seems capable of resuming its normal duties, the amount of blood the device pumps can be gradually reduced until the patient's heart has taken over completely. When this is done, the pump is then disconnected and the patient's chest sewn up.