The Jarvik 7 Heart Today

Since its debut, the Jarvik 7 Total Artificial Heart has become more used as a temporary substitute for those patients that are awaiting a heart transplant. Since the first implant in 1982, the Jarvik 7 has been used in more than three hundred and fifty patients and is still in use today. The Jarvik 7 patients had an average life expectancy of days to weeks before they received the Jarvik 7. After receiving the artificial heart, the patients lived an average of ten months, but the rate of complication was high. Due to this complication rate, the media only reported on the heart’s failures and not its successes. “"That's where the press stopped doing research and checking facts and instead began to publish mistake after mistake after mistake," Dr. Jarvik notes” [4] While the media was reporting falsities, the doctors working with the Jarvik 7 were able to better familiarize themselves with the device and so were able to better assist patients who needed this heart. Dr. Jarvik stated, “Very rarely did I receive a phone call to check the facts. For example, the press wrote repeatedly that Dr. Clark [the first recipient of the Jarvik 7 artificial heart] died of a stroke. In fact, he never had a stroke at all. The press wrote over and over that the console a patient needed to power the heart was 'as large as a refrigerator.' In fact, the home console is about half that size, but more significantly — the portable power system was only the size of a briefcase" [4]. Dr. Jarvik also said the “press also wrote that the Jarvik 7 heart caused a high rate of strokes and infections. The press didn't notice that as more cases were done, these rates plummeted, yet the device was the same. So the device alone was never responsible for the earlier complications. Rather, doctors needed to learn how to manage their patients more effectively: That is the point of such research in the first place” [4]. The most incorrect of all of these statements however, is the one that says that the Jarvik 7 heart was a failure. The Jarvik 7 artificial heart has had the highest success rate of any total artificial heart or heart assist device in the history of such devices [4]. The heart is now available in the United States, Canada, Germany , and France under its new ownership and renamed the CardioWest total artificial heart [4].

Picture of Jarvik 7 heart courtesy of http://www.medicineandbiotech.com/
Information courtesy of
[4] http://www.jarvikheart.com/basic.asp?id=69

The Drawbacks of the Jarvik-7 Total Artificial Heart

However, the Jarvik-7 total artificial heart does have its drawbacks. In the US national clinical trial, there were many failures along with the successes of the Jarvik-7 total artificial heart. The most common source of morbidity (a diseased state) was infection which occurred in ninety percent of the patients, but only in ten percent was the infection considered severe [2]. No serious neurologic events caused death, but there were “three seizures, two episodes of impaired state of consciousness, one retinal hemorrhage, one retinal embolus [a mass of clotted blood] and one cerebrovascular accident” [2].

Picture of Jarvik-7 heart courtesy of commons.wikimedia.org

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.

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...

An Introduction to the Artificial Heart

Each year heart failure takes the lives of roughly 250,000 people in the United States alone [1]. The total artificial heart (picture to the left) will become an essential tool to the survival of many Americans as time passes and the baby boomers begin to age. Also, as obesity becomes an increasing problem, so will heart failure, and the need for heart transplants. Fortunately, technology has increased dramatically and the total artificial heart is becoming more successful. DeBakey designed the first “mechanical circulatory support device” and it was implanted in a patient in the year 1963 [1]. However, progress on the artificial heart slowed soon after until the Jarvik-7 heart invented by Dr. Robert Jarvik (picture to the right) was first implanted in December of 1982 in a patient in Utah [1]. Unfortunately, the patient died four months later of infection due to the artificial heart being both inside and outside of the body [1]. The trend of total artificial heart implantations slowed due to the failure of the Jarvik-7 heart and shifted to blood pumps and counterpulsation devices. Blood pumps come in two forms: pulsatile and non-pulsatile. Pulsatile devices are first generation, new technological devices that have valves and simulate the pulsating nature of the human heart [1]. Non-pulsatile devices are turbine pumps and are simpler and less expensive than pulsatile devices [1]. Counterpulsation devices compress the aorta, a section of the heart that pumps the blood through, in order to increase blood flow from the heart. Mechanical support may be temporary or permanent with temporary being the most commonly used form [1]. Even though the Jarvik-7 total artificial heart failed at first, it continues to be the one of the earliest and most used of the total artificial heart systems.

Picture of artificial heart courtesy www.britannica.com

Picture of Dr. Robert Jarvik courtesy www.jarvikheart.com

Information courtesy of

[1] Esmore D, Rosenfeldt F L. Mechanical Circulatory Support for the Failing Heart: Past, Present and Future. [editorial] Heart and Lung Circulation [serial on the Internet]. 2005 [cited 2008 Feb. 28];14(3):163-166. Available from: http://www.scopus.com/scopus/record/display.url?view=b..