Three nationally prominent Boston heart specialists, in seperate interviews this weekend, have expressed reservations over the recent series of heart transplant operations.

Dr. Alexander Nadas, clinical professor of pediatrics and chief of cardiology at Children's Hospital, said the operations "raise immensely difficult ethical problems. The medical profession," he added, "may be stumbling into them without considering all the implications."

Possibly Donor Shortage

"You have to have someone dead to take his heart," Nadas noted. "Granted we are killing 50,000 persons per year on our highways, but there still is a possibility of a shortage of donors. One imagines the prospect of vultures waiting for these people to die."

"Do you say it is the job of the Doctor to keep people alive, or do you say, 'Now we turn this one off in order to give another one life?" Nadas asked. "If grandfather is getting hard to take care of...if medicare money is running out...it is a very difficult problem."

Nadas stressed that he had no evidence that any of the donors in the five recent transplant cases had been abused.

Dr. W. Gerald Austen, professor of surgery and chief of the surgical cardio-vascular unit at Massachusetts General Hospital, agreed with Nadas that the ethical implications of heart transplant operations needed further study. "I wouldn't want to imply that the ones that have been done haven't been done just right ethically," he added.

"The sooner you take a donor," he noted, "the better the donor organ is going to be. Say you wait 24 hours. At present you can't use those organs." Asked if he foresaw a possible black market of hearts, Austen replied, "If these operations eventually prove to be worthwhile, then it will get tough. I just can't see how physicians could be influenced by anything but need, but I know that's naive. Somewhere it's going to have to be pretty carefully thought out."

Dog Problems

Austen acknowledged that a lot of work had been done on heart transplants in dogs prior to the human operations, but he would not characterize the results as favorable. "We do know," he said, "that in the great majority of cases with dogs they run into a lot of problems, some dogs live for a long perod of time though, that is to say, for months."

Dr. Robert E. Gross, William E. Ladd Professor of Child Surgery and chief of the surgical cardio-vascular unit at Children's Hospital, also questioned how complete the information on dog transplants is.

Publicity Misleading

"There are two problems," he said, "the surgical problem of whether you can take a heart out and sew it back in and the problem of the immune reaction: will the body tolerate the thing?" He said sufficient work had been done on the first aspect, but added, "I realize there comes a point when you have to try it out on humans. They don't react the same way a dog or a cat does. I personally would have liked to have seen more work done on the immune reaction in dogs first."

Nadas expressed the fear that the publicity may lead people to "the false hope that they can buy a new heart from the heart bank. I'm worried that people may think this is nearer and more available than it is."