But not everyone is celebrating the surgery’s results. Dr. Robert Jarvik, 55, the man who conducted the first artificial-heart experiment nearly two decades ago, has some reservations. Jarvik’s pioneering Jarvik-7 caused a similar buzz of excitement when it was first implanted in 1982. But complications quickly developed and Jarvik eventually redirected his research from artificial hearts to another medical miracle, devices that prolong the life of a natural heart.

NEWSWEEK: Are there problems and risks associated with the AbioCor technology that are not being acknowledged?

Dr. Robert Jarvik: People should realize that the AbioCor will serve a very limited population. Heart-replacement devices are probably going to be needed in less than 1 percent of heart-failure patients. That means that heart-assist devices, which are another type of artificial heart that have been used in thousands of patients, are the type of technology that has the real potential to make an impact on heart disease. The AbioCor is so large that it won’t fit most of the population. It will fit in patients who are larger than 200 pounds, maybe some patients that are in the range of 180, depending on the shape of their chests. It will fit in practically no women in the U.S. population.

So you think the usefulness of the device is being blown out of proportion in the extensive media coverage?

I think it’s completely misunderstood because of something to do with drama, not science.

What is a heart-assist device? How does it work?

When the heart is failing, it usually becomes very much enlarged. As it becomes enlarged, it becomes less efficient-it takes a lot of work to pump the same amount of blood against the same pressure. If you assist the heart with a booster pump, the size of the heart gets smaller. It becomes more effective, pumps on its own, and improves. Then the assist device works together with the heart; the natural heart does some of the work and the assist device does some of the work. As the patient’s own heart recovers, then the patient’s own heart works as a backup for the device…. The vast majority of experts in this field are working on heart-assist devices. If people called them artificial hearts, which they really are, then the public would have paid some attention. But the AbioCor is identified as an artificial heart as if it were different.

Do you think the AbioCor experiment is irresponsible?

No, it’s excellent research work. But I’d hate to see this research presented as if it has real likelihood in the near future of providing the American public with something that has an impact on heart disease. The chances of that are nil. What can happen is that we go into a round of public misunderstanding and public disappointment that is damaging to the whole field.

Do you see similarities in the response to this experiment and your attempt to install an artificial heart nearly two decades ago?

At the time of the Jarvik-7, there was a lot of enthusiasm and a lot of positive interest. And then there were some complications with the patients. The negatives became emphasized to the point where if you go online today and search “Jarvik-7 heart,” the articles will tell you that Barney Clark, the first patient, died of massive strokes. It’s untrue. Medical research needs time. The first impression is usually not scientifically valid. It may or may not be right or wrong but is usually not scientifically valid.

What made you shift your interest from total-heart-implant technology to heart-assist devices?

It became clear that a heart-assist device was going to be better than a replacement heart because it was going to be more practical. You need something that’s the size of a pacemaker that can fit in a large number of patients.

Does any of your criticism of the AbioCor stem from the fact that you conducted a similar artificial heart experiment which was ultimately perceived as unsuccessful?

Well, that’s exactly the reason. The Jarvik-7 has been used in hundreds of patients. It’s used as a holdover in a patient waiting for a donor heart. In recent years it had better than a 90 percent success rate. And the types of complications that it had early on became very, very rare after medical management was learned. What happened with the Jarvik-7 is that the learning curve, the time it took to learn how to properly medically manage the patients, had to be done in humans, and there were some difficulties. Those difficulties became greatly exaggerated, to the point where they have been really almost vilified in the press, and it’s ridiculous. The same thing is going to happen to the AbioCor if they have a bad result. It’s not going to be a fair scientific judgment of their technology. You need to be able to do the experiment to analyze the results fairly. You don’t need the press guessing and second guessing things and presenting to the public something that is poorly understood and vastly exaggerated. The mistakes in credible, balanced news sources are huge. The press is not doing a very good job of fact-checking.

Do you have any regrets about your early experiment with the Jarvik-7 heart transplant?

No.