Proponents of artificial hearts fear the Food and Drug Administration's withdrawal of approval for the Jarvik heart could hurt research toward a totally implantable device, but most see it as a temporary setback. And they don't believe the action will have a serious impact on heart patients because other temporary heart-assist devices still are available as a bridge to a heart transplant. ``It is a shame because the Jarvik, for its limitation, did make some positive contributions,'' said Dr. Antonio Gotto, chief of internal medical services at Baylor College of Medicine in Houston and past president of the American Heart Association. ``I hope this will be only a temporary, not a permanent, setback toward the goal of achieving a totally implantable heart.'' The FDA informed Symbion Inc. of Tempe, Ariz., this week that it was withdrawing approval for continued investigational uses of its artificial heart, both as a permanent replacement and a temporary bridge for patients awaiting a human heart transplant. The Jarvik heart, named after its inventor, Dr. Robert Jarvik, gained household recognition after it was implanted in Barney Clark on Dec. 2, 1982. He lived 112 days, his new heart tethered to a bulky external power system, before he succumbed to multiple organ failure. In revoking Symbion's approval, the FDA said it had found ``serious deficiencies'' in manufacturing quality control, monitoring of research sites, servicing of equipment, training of personnel and reporting of adverse reactions to FDA. Dr. Donald Olsen, director of the University of Utah's Institute for Biomedical Engineering, said he was ``surprised and disappointed'' by the FDA's action and hoped it would not hurt future federal funding of artificial heart research in general, particularly for totally implantable devices. ``Our concern, of course, is that this particular publicity will not have a negative influence'' on artificial heart development in general, said Olsen. ``But I would like to make sure (people know) that the artificial heart did not fail; it was a failure on the part of Symbion to meet the requirements of the FDA'' for improving the device. Gerson Rosenberg, a biomedical engineer who leads Pennsylvania State University's efforts to design an electric heart, said he did not think the decision to pull the Jarvik would hinder research. But others felt the decision could slow research in the field. ``By removing the Jarvik, you take the first and main artificial heart player out of the ballgame,'' said Dr. Jacob Kolff, who heads Temple University's efforts to develop the temporary ``Philadelphia Heart.'' ``That leaves a bit of a vacuum for those researchers who think there may be a future for an artificial heart,'' said the surgeon, whose father, Dr. Willem Kolff, developed the first artificial kidney in 1943. Withdrawal of the permanent Jarvik heart leaves only one other natural-heart replacement with FDA investigational approval, but that device is used only as a temporary bridge and only at Hershey Medical Center of Penn State. Other companies have approvals for temporary implants and for left ventricular assist pumps that help the natural heart work without replacement.