Five Jehovah's Witnesses who received heart transplants at the Texas Heart Institute in Houston did not receive blood transfusions during the highly complicated surgery.
Heart transplant surgery usually requires that a patient receive between two and eight units of blood, depending on the patient's general condition.
Because of their religious beliefs, Jehovah's Witnesses refuse blood transfusions for any reason, even if it means the sick person will die.
All five Jehovah's Witnesses were men between the ages of 35 and 53 whose hearts had been damaged by a viral infection, but otherwise were in good health.
To avoid transfusions, the Houston team used surgical techniques that limited the loss of blood during the operation and special vacuums to recover any lost blood.
All of the patients survived surgery and recovered. One later died because he neglected to take the drugs needed to prevent rejection of the transplanted organ. The other four men are still alive.
But the technological feat raises ethical questions because of the scarcity of donor hearts.
In a commentary that followed the Texas report published in the Archives of Surgery, William A. Gay Jr. of the University of Utah School of Medicine pointed out that if these patients died because they had refused transfusions, "The net loss would be two lives, not one: the patient who actually died and the potential recipient who did not receive the donor organ."