The first successful heart transplant operation in the world was carried out by Dr. Christiaan Barnard in South Africa in December 1967. From that time until the present day, the only accepted way to preserve a donor heart has been to pack it in ice inside a cooler box. Even then, the heart will usually only be viable, and capable of being transplanted, for between four to six hours.
The existing system is that donor hearts are transported in their cool boxes between hospitals by the speediest means possible. Depending on geography, this usually means the heart is sent either by road, air, or a combination of the two. The problems of this are obvious; traffic jams, bad weather, or mechanical difficulties can cause such serious delays that the heart may not arrive in time.
Additionally, a heart can be damaged when it’s warmed up at the end of the surgery. The time constraint means that the heart can’t be tested to see if it works until after the transplant operation. Statistically, from five percent to seven percent of hearts don’t work after they’ve been transplanted. The psychological effect on the recipient, and the surgical team, can be traumatic.
But, according to pediatric heart surgeon Dr Mark Plunkett, all that may soon change. A new heart-preservation system has been designed which maintains the organ in a warm, beating and functioning physiological state outside of the body. The sterile box is made by TransMedics Inc. in Andover, MA. It is heated, and includes a small device that pumps warm, oxygenated donor blood through the heart the entire time it’s in transit. This means that the heart can keep beating outside the donor body for up to 12 hours. The still-beating heart can also be monitored en route to keep it in optimal condition.
Dr. Abbas Ardehali is surgical director of the UCLA Heart and Lung Transplant Program. He is a principal investigator of the Organ Care System trial in the U.S. The UCLA website, in referring to the trials taking place, reports Dr Ardehali as saying, “Human hearts were never meant to be put on ice in a cooler.” Testing is taking place of the new concept – now renamed “Heart in a Box” – not only at UCLA, but also at a number of other leading heart transplant centers across the country.
“If we’re able to safely transport donor hearts across longer distances, from the East Coast to the West Coast for example, we may be able to increase the pool of donor hearts available to patients,” Dr. Ardehali says.
An additional benefit of the new system is the ability to more comprehensively assess the heart prior to implantation. This should lead to improved immediate and long-term heart function, reduce the risk of organ rejection and thus increase the number of hearts available for transplant. Cardiologist Ann Hickey, M.D., medical director of the UCLA Heart Transplant Program, is unhappy that a lot of donor hearts are currently discarded. She claims that if there were more time to get a better look at the heart prior to transplantation some of the donor hearts could be used that would have otherwise been rejected.
The UCLA states on its website that it expects the results of the trial, which will specifically evaluate whether the new system extends the amount of time available to transfer the heart from donor to recipient, to be available within the next two years.
The Cleveland Clinic is another of the hospitals participating in the testing of the “Heart in a Box” system. They mention that the popular TV show, Grey’s Anatomy has featured the “Heart in A Box,” leading some people to believe that it was a made-up invention. But the system is very real; in fact, it’s already in use in Europe.
The objective of UCLA’s testing is to ensure that the system works well enough to be approved by the FDA. The eventual hope is to demonstrate that the patient gets a healthier heart, with less chance of rejection and a reduced risk of death. Dr. Mark Plunkett and other industry experts believe that this system for extending the period during which a donor heart can be preserved is a tremendous medical advancement.