The access device consists of two small tubes that lead from the pumping bladder within the aorta to a port on the skin. One tube relays information about the heart's timing and electrical activity to an attached computer. The other tube allows the external drive to pump air in and out to inflate and deflate the bladder. To reduce the risk of infections, the access device is pre-coated with a thin layer of cells derived from the patient's skin and grown in the laboratory for about a week. The external drive unit controls pump timing and powers the bladder.
Patients receive two interchangeable drivers.
The rechargeable batteries last about two hours. Heart failure, the inability of the heart to keep up with its workload of pumping blood to the lungs and the rest of the body, has become increasingly common as the baby boom generation enters old age. An estimated 4.8 million people, twice as many as 10 years ago, have congestive heart failure, which can usually be controlled with medication. More than 400,000 new cases are diagnosed each year. About 40,000 people currently suffer from end-stage heart failure.