Even though the supply of hearts available for transplantation remains well below the demand, an international panel recently expanded the eligibility criteria for determining which people might receive the life-saving surgery.

Heart transplants are the last resort for people with severe heart failure. Patients so weak and breathless that they need a transplant have only about a 50 percent chance of living for another year without one, according to Dr. Mandeep Mehra, head of cardiology at the University of Maryland Medical Center. However, after a heart transplant, these patients have a 50-50 chance of living another 10 years. A man in Ohio is the longest survivor of a heart transplant — 28 years.

Dr. Mehra led a panel from the International Society for Heart and Lung Transplants (ISHLT) that issued the following new guidelines that make even more people than before eligible for heart transplants:

• The upper age limit for a heart transplant recipient was raised from age 65 to 70. Even patients over age 70 could be considered for transplants if they agree to receive hearts from donors over age 50 — hearts that most transplant centers do not accept.
• Obese patients who can lower their body mass index (BMI) to 30 prior to transplant.
• Patients with well-controlled diabetes who are relatively free of the disorder's late complications, which produce eye, kidney, or nerve damage.
• People with cancer that is responding to treatment.

Transplants are not recommended for morbidly obese individuals (BMI greater than 40, or roughly 100 pounds over their ideal body weight), cigarette smokers, and abusers of alcohol or drugs who have not quit well before surgery.

These guidelines are of course just that — suggestions — and each transplant center remains free to make its own decisions on which patients they will select for transplant. At each center, a panel of doctors, social workers, psychologists, and others decide on which patients will be placed on their waiting list.

Broadening the eligibility criteria for transplants seems to fly in the face of the limited number of available hearts. In October 2006, 2,869 people in the U.S. were on the waiting list for a new heart.

The preceding year, 2,125 patients received new hearts and 416 died while still waiting. The scarce hearts are allocated to transplant centers by the United Network for Organ Sharing, which bases its decisions on a number of factors, including how long someone has been on the waiting list. 

Another panel from the ISHLT addressed this issue of scarcity by proposing that physicians make better use of new drugs, pacemakers, and other devices that can lengthen survival for patients with heart failure. In this way, the need for transplant can be avoided or delayed, and the number of people on the waiting list can be reduced.