If you watch the Steven Soderbergh-directed TV show The Knick, you’re probably familiar with how much things changed in the medical field since the early 1900s: a lot! It’s sometimes hard to believe how much progress has been accomplished in a century, but also how long some discoveries were made. I personally was surprised to read that I’m as old as the first implantation of an artificial heart. I would have thought that it was a more recent breakthrough.
Who Invented the Artificial Heart?
In 1937, Soviet scientist Vladimir Demikhov who at that time was still a 4th year student implanted an artificial heart into a dog, marking one of the earliest attempts at creating an artificial heart—the apparatus was able to maintain the circulation in a dog with an excised heart for five hours and a half. The device consisted of two adjacent diaphragm pumps working as two cardiac ventricles and its size was almost identical to that of the native dog’s heart.
At that time and for a long time, Demikhov’s work was not taken seriously as what he tried to accomplish seemed so improbable. So, despite his pioneering work in organ transplantation, he is more famous for his head transplant experiments on dogs.
The Heart of the Ventriloquist
If you watched The Paul Winchell Show on NBC during the first half of the 1950s, it’s highly probable that you couldn’t think of ventriloquist and comedian Paul Winchell who would one day become an innovator with a medical degree. And yet, it happened. He began his studies at Columbia University in 1959 and completed them in 1974 after earning his degree from The Acupuncture Research College of Los Angeles. He had served as a medical hypnotist at the Gibbs Institute in Hollywood.
One day, after appearing in the “Arthur Murray Dance Party” Show, Winchell met Dr. Henry Heimlich, the inventor of the Heimlich maneuver, and they became friends. While observing Heimlich doing surgery, the comedian had an idea for creating an artificial heart and, with the help of the surgeon, he designed it, built a prototype, and filed for a patent in 1956 (he received it in 1963).
Winchell received a total of 30 patents including a blood plasma defroster, a retractable fountain pen, a flameless cigarette lighter, a disposable razor, battery-heated gloves, and more.
The Liotta-Cooley Total Artificial Heart
The Texas Heart Institute’s founder, Dr. Denton A. Cooley, carried out a groundbreaking operation on April 4, 1969, which would become known as an important medical milestone. With the world’s first total artificial heart implanted by Dr. Cooley, the search for a practical and workable treatment for patients with severe heart failure officially began. Dr. Domingo Liotta, who had created the artificial heart device, worked with others to make this historic occurrence happen.
The Liotta-Cooley total artificial heart was a cutting-edge, double ventricle, air-driven (pneumatic) device that mimicked the structure and operation of a normal heart. Wada-Cutter hingeless valves successfully regulated the intake and outflow zones of the pump, controlling the blood flow. The pump chambers, input routes, and outflow tracts were lined with a specific fabric to guarantee biocompatibility and lower the possibility of clot formation. This material encouraged the development of an even cellular surface.
A crucial idea that transformed the area of cardiac care was made clear by the success of the Liotta-Cooley total artificial heart implantation: patients may be “bridged” to transplantation. This meant that patients could be kept alive with mechanical circulatory support devices, such as the entire artificial heart, while they waited for a suitable donor heart to be found for transplantation.
The patient who received the Liotta-Cooley artificial heart lived for almost three days with the device, effectively demonstrating that mechanical devices could serve as lifesaving bridges until a human heart became available for transplantation. This achievement not only showcased the potential of artificial hearts but also ignited a new era of research and development in the field of mechanical circulatory support.
Jarvik-7: The First Implantation
Inspired by his mentor, Dr. Willem Kolff, who was a pioneer in the field of artificial organs and had previously developed the first practical kidney dialysis machine, American scientist Dr. Robert Jarvik developed the Jarvik-7 artificial heart—despite Dr. Heimlich’s claims, he denies having used Paul Winchell’s design.
The Jarvik-7’s two biocompatible polyurethane ventricles, which serve as the heart’s pumping chambers, were developed to mimic the structure and operation of a real heart. The patient’s native arteries and veins were joined to the ventricles. An external air compressor supplied the device with power, forcing air into the ventricles to cause them to constrict and pump blood.
The first person to get the Jarvik-7 implant was Seattle dentist Dr. Barney Clark in 1982, which was a groundbreaking accomplishment in medical history. The landmark operation was performed by American cardiothoracic surgeon Dr. William DeVries. Dr. Clark was able to live for 112 days after the operation because of the Jarvik-7 artificial heart.
The Jarvik-7 had several difficulties and restrictions. One significant problem was the massive external air compressor needed to power the device, which limited patients’ movement. Additionally, because of the mechanical design of the device and the requirement for blood-thinning drugs, blood clotting and bleeding issues were frequent.
Despite its drawbacks and difficulties, the Jarvik-7 had a significant influence on the practice of cardiac medicine. It proved that it was possible to keep a patient alive for a long time after having an artificial heart implanted. The information gleaned from the Jarvik-7 set the path for later developments in artificial heart technology, including more portable and effective devices that may serve as stepping stones to transplantation.
Artificial Hearts Beyond the Jarvik-7
Later versions of the artificial heart showed increased success rates after Clark’s operation. The second Jarvik-7 patient showed the possibility for prolonged longevity by surviving for 620 days following implantation. However, issues including the possibility of infection and the requirement for external power sources persisted.
In the 1990s and the beginning of the 2000s, total artificial hearts and ventricular assist devices (VADs) became more common. In order to assist failing hearts while waiting for transplants, VADs became important instruments. These devices were still being improved, with an emphasis on enhancing their resilience, biocompatibility, and control systems.
With fewer than 2000 implants, the use of mechanical hearts remained relatively limited despite breakthroughs. The SynCardia temporary Total Artificial Heart, which was used in the majority of artificial heart transplants, became the most popular form of artificial heart.