Rafed English
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An artificial heart is a mechanical device that replaces the heart. Artificial hearts are typically used to bridge the time to heart transplantation, or to permanently replace the heart in case transplantation is impossible. Although other similar inventions preceded it going back to the late 1940's, some used successfully on dogs, the first artificial heart to be successfully implanted in a human, was the Jarvik-7, designed by Paul Winchell and also attributed to Robert Jarvik and implemented in 1982. The first two patients to receive these hearts, Barney Clark and William Schroeder, survived 112 and 620 days beyond their surgeries, respectively. [1]

An artificial heart is also distinct from a cardiopulmonary bypass machine (CPB), which is an external device used to provide the functions of both the heart and lungs. CPBs are only used for a few hours at a time, most commonly during heart surgery.

SynCardia temporary Total Artificial Heart

The SynCardia temporary Total Artificial Heart was the first FDA-approved total artificial heart. It received FDA approval on October 15, 2004, following a 10-year clinical study.[2]

Originally designed as a permanent replacement heart, it is currently approved as a bridge to human heart transplant for patients dying because both sides of their hearts are failing (irreversible end stage biventricular failure).[2] There have been more than 900 implants of the Total Artificial Heart, accounting for more than 210 patient years of life on this device.[3]

During the 10-year study, 79% of patients receiving the Total Artificial Heart survived to transplant (New England Journal of Medicine 2004; 351: 859–867).[4] This is the highest bridge-to-transplant rate for any heart device in the world.[3] (See FDA Summary of Safety and Effectiveness)

AbioCor Replacement Heart


Unlike the CardioWest TAH, the AbioCor Replacement Heart by AbioMed is fully implantable, meaning that no wires or tubes penetrate the skin, and, therefore, there is less risk of infection.

The AbioCor is approved for use in severe biventricular end-stage heart disease patients who are not eligible for heart transplant and have no other viable treatment options.[5] As of April 2011, 14 patients have been implanted with the AbioCor, with one patient living for 512 days with the AbioCor.[6]

The AbioCor received FDA approval under a Humanitarian Device Exemption (HDE) on September 5, 2006.[7] The first implant of the AbioCor since receiving FDA approval in 2006 took place on June 24, 2009, at Robert Wood Johnson University Hospital, New Brunswick, New Jersey.[8] This patient later died on August 23, 2009.[9] (See FDA Summary of Safety and Probable Benefit.)

Origins

A synthetic replacement for the heart remains one of the long-sought holy grails of modern medicine. The obvious benefit of a functional artificial heart would be to lower the need for heart transplants, because the demand for organs always greatly exceeds supply.

Although the heart is conceptually 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.

Early development

A heart-lung machine was used in 1953 during a successful open heart surgery. Dr. John Heysham Gibbon, the inventor of the machine, performed the operation and developed the heart-lung substitute himself.

Although Jarvik created the idea and rough draft for the artificial heart, his models were not created of a material that the human body would accept. Dayton, Ohio's Ival O. Salyer, along with various colleagues, developed a polymer material that the human body would not necessarily reject.

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.[10][11]

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."[12]

The scientific interest for the development of a solution for heart disease developed in different research groups worldwide.