Cardiac (heart) assist devices differ from the TAH, in that the patient’s heart is not removed during implantation. Assist devices may include either a Left Ventricular Assist Device (LVAD) or a Right Ventricular Assist Device (RVAD) or both. As opposed to TAH implantation, the assist device serves to provide only a part of the total cardiac output of the patient’s heart.
Although the heart is conceptually simple (basically a muscle that functions as a pump), it embodies subtleties that defy straightforward emulation with synthetic materials and power supplies. Consequences of these issues include severe foreign-body rejection and external batteries that limit patient mobility. These complications limited the lifespan of early human recipients to hours or days.
On July 3, 1952, 41-year-old Henry Opitek suffering from shortness of breath made medical history at Harper University Hospital at Wayne State University in Michigan. The Dodrill-GMR heart machine, considered to be the first operational mechanical heart was successfully used while performing heart surgery.
Dr. Forest Dewey Dodrill used the machine in 1952 to bypass Henry Opitek’s left ventricle for 50 minutes while he opened the patient's left atrium and worked to repair the mitral valve. In Dr. Dodrill’s post operative report he notes, “To our knowledge, this is the first instance of survival of a patient when a mechanical heart mechanism was used to take over the complete body function of maintaining the blood supply of the body while the heart was open and operated on.
The scientific interest for the development of a solution for heart disease developed in different research groups worldwide.
In 1958 Domingo Liotta started the studies of TAH replacement at Lyon, France and in 1959-60 at the National University of Cordoba, Argentina. He presented his work at the meeting of the American Society for Artificial Internal Organs meeting held in Atlantic City in March 1961. On that meeting Dr Liotta described the implantation of three types of orthotopic (inside the pericardial sac) TAH in dogs, each of which used a different source of external energy: an implantable electric motor, an implantable rotating pump with an external electric motor and a pneumatic pump.
In the afternoon of April 21 1966 Michael DeBakey and Liotta implanted the first clinical LVAD in a paracorporeal position (where the external pump rests at the side of the patient) at the Methodist Hospital in Houston, in a patient experiencing cardiogenic shock after heart surgery. The patient developed neurological and pulmonary complications and died after few days of LVAD mechanical support. In October 1966 DeBakey and Liotta implanted the paracorporeal Liotta-DeBakey LVAD in a new patient who recovered well, and was discharged from hospital after 10 days of mechanical support, thus constituting the first successful use of an LVAD for postcardiotomy shock.
In the morning of April 4 1969 Liotta and Denton A. Cooley replaced a dying man’s heart with a mechanical heart inside the chest at the Texas Heart Institute in Houston as a bridge for a transplant. The patient woke up and recovered well. After 64 hours the pneumatic powered artificial heart was removed and replaced by a donor heart. Replacing the artificial heart proved to be a bad decision, however; thirty-two hours after transplantation the patient died of what was later proved to be an acute pulmonary infection, extended to both lungs, caused by fungi, most likely caused by an immunosuppressive drugs complication. If they had left the artificial heart in place the patient may have lived longer.
The original prototype of Liotta-Cooley artificial heart used in this historic operation is prominently displayed in The Smithsonian Museum "Treasures of American History" exhibit in Washington, DC.
Contrary to popular belief and erroneous articles in several periodicals, the Jarvik heart was not banned for permanent use. Since 1982 more than 350 people have received the Jarvik heart. http://www.jarvikheart.com/basic.asp?id=69
With increased understanding of the heart and continuing improvements in prosthetics engineering, computer science, electronics, battery technology, and fuel cells, a practical artificial heart may become a reality.
The first heart assist device was FDA approved in 1994, and two more received approval in 1998. While the original assist devices emulated the pulsating heart newer versions, such as the Heartmate II, developed by the Texas Heart Institute of Houston, Texas, provide continuous flow. These pumps (which may be centrifugal or axial flow) are smaller and potentially more durable and long-lasting than the current generation of total heart replacement pumps. Another major advantage of a VAD is that the patient can keep the natural heart, which can receive signals from the brain to increase and decrease the heart rate as needed. With the completely mechanical systems, the heart rate is fixed.
Several continuous flow ventricular assist devices have been approved for use in the European Union and as at August 2007 were undergoing clinical trials for FDA approval.
In the fictional Star Trek universe, Captain Jean-Luc Picard had an artificial heart implanted in 2327, which was later replaced. A power surge from it almost killed him in 2369. Joseph Sisko, father of Benjamin Sisko, had several artificial organs, including a new aorta he received in 2372.
The British science fiction series Space: 1999 had a character, Victor Bergman (portrayed by Barry Morse), with an artificial heart. He was able to modify its rate of operation with a wrist-worn device.
The novels of Philip K. Dick feature the use of 'artiforgs' or artificial organs.
In the 1981 movie Threshold, it is stated from IMDB, that "The celebrated heart surgeon Dr. Vrain supports the research of the offbeat scientist Aldo Gehring, who is inventing an artificial heart. Dr. Vrain performs the first artificial human heart transplant against the advice of the Ethics Committee." This movie, which stars Donald Sutherland and Mare Winningham, is a study in artificial heart transplant, though it is fictional.
In the 1987 movie Robocop, there is a commercial for an artificial heart clinic called "The Family Heart Center" where surgeons operate on persons and implant artificial hearts from "the complete line of hearts by Jensen and Yamaha," encouraging its customers "You pick the heart!" These hearts come with extended warranties, financing, and qualify for "health tax credit."
The computer game Syndicate (by Bullfrog) features humans agents the player can modify bionically, including replacing the heart with more and more advanced technology.
In the anime series Sentou Yousei Yukikaze, the engineer Tom "Tomahawk" John possesses a nuclear-powered artificial heart. While this allowed him to be nearly fully mobile, the fact that it used nuclear power prevents him from visiting some foreign countries.
In the 1986 sequel King Kong Lives, King Kong, after being shot down from the World Trade Center, is kept alive in a coma for about 10 years at the Atlantic Institute, under the care of surgeon Dr. Amy Franklin (Linda Hamilton). In order to save Kong's life, Dr. Franklin must perform a heart transplant and give Kong a computer-monitored artificial heart.
A risky practice?: As more angioplasties are performed, some doctors want patients to know that not having a heart surgeon on site can be dangerous.
Sep 03, 2006; Byline: John Fauber Sep. 3--When her cardiologist recommended a heart catheterization and possible angioplasty, Patricia Stropes...