About the Jarvik-7 Total Artificial Heart

The Jarvik-7 total artificial heart (picture to the left) is a pneumatic (operated by air pressure) biventricular (pertaining to both ventricles of the heart) pump. It consists of two ventricles connected to the main blood vessels that are naturally in the body [2]. It also has an air-drive line that runs out of each of the ventricles and through the skin and connects to a large console that pumps out pressurized air and monitors the pump function of the heart [2]. Each of the ventricles has a spherical polyurethane chamber half of which is immobile and the other half of which is a mobile four-layered diaphragm [2]. “Pulses of air pressure from the console push the diaphragm and thus blood is ejected from the chamber” [2]. There are mechanical valves located at the inflow and outflow of both of the chambers that provide for unidirectional blood flow [2]. The most that a chamber can hold at once is seventy milliliters, and the artificial heart can pump anywhere from six to eight liters per minute [2].

The Jarvik-7 total artificial heart (early model shown to the left) was banned by the Food and Drug Administration in 1990 after many failed implantations. The device was then renamed the CardioWest C-70 and a few minor, unspecified changes were made and it was approved by the Food and Drug Administration for clinical trials in the USA [3]. In one study, many total artificial hearts were observed and it was maintained that the Jarvik-7 total artificial heart was the “gold standard” [3]. The study was conducted over a period of more than fifteen years. The study found that the total artificial heart Jarvik-7 is a safe and efficient substitute for the human heart in patients that are awaiting heart transplantation. In the study, good cardiac output was seen on the first day after the total artificial heart was implanted in all of the patients. The total artificial heart system did allow for long term support in one patient up to 602 days, more than three months in four other patients, and greater than six months in two more patients. The Jarvik-7 total artificial heart has allowed for many patients with heart failure to live until a human heart becomes available for transplant [3]. The picture that follows is of an implanted Jarvik-7 artificial heart.

First picture of the Jarvik 7 heart courtesy of http://www.thebakken.org/

Second picture of the Jarvik-7 heart courtesy of http://www.smithsonianlegacies.si.edu/

The picture of the implanted heart courtesy of http://www.fi.edu/

Information from

[2] Lavee J, Paz Y. Mechanical Alternatives to the Human Heart: Intracorporeal Assist Systems and Total Artificial Heart, Israel Medical Association Journal 2002; 4 (3): 209-212. Available from: http://www.ima.org.il/imaj/ar02mar-16.pdf. Accessed 2008 Mar. 29.

[3] Leprince P, Bonnet N, Rama A, et. al.. Bridge to Transplantation With the Jarvik-7 (CardioWest) Total Artificial Heart: A Single-Center 15 Year Experience. Journal of Heart and Lung Transplantation [serial on the Internet]. 2003 [cited 2008 Feb. 28];22(12):1296-1303. Available from: http://www.scopus.com/scopus/record/display.url?view=b...