In his own way, Dr. Risteard Mulcahy is bringing the new wave in medicine to Europe.

Not only does he believe in prevention, a concept still considered rather daring in much of the European medical community, but he talks about it, teaches it, even writes about it.

"In Ireland now," says Mulcahy (founder of the Irish Heart Foundation and the head of the Heart Disease Unit at Dublin's St. Vincent's Hospital), "even for a doctor to come out in public on an issue like this (public education about preventive medicine) is considered somewhat unconventional, almost unprofessional."

You can't actually call Mulcahy holistic, but sometimes he sounds like it. For example, "People's health, and indeed their happiness, depends entirely on themselves, and we're far too naive in our ideas about what doctors can do for us and what hospitals can do for us.

"In fact," he says, "with most of these chronic diseases like heart disease, cancer, bronchitis, there's very little we can do. You can alleviate symptoms, get people over the acute attack or exacerbations, but that's really most of it."

Mulcahy was in the U.S. recently to meet with cardiology colleagues at the Mayo Clinic in Rochester, Minn., and devise ways of pursuing his passion: educating Europeans to the urgent need for life- and eating-style revolutions. e

"There is a beginning," he says, "but we're way behind the Americans. We haven't yet started to change our food habits substantially, although no doubt we will . . . yes, I think Europe is beginning to wake up, but it's terribly slow."

Mulcahy has written a kind of healthy-heart Baedecker called "Beat Heart Disease! A Positive Guide," published in the U.S. by Arco Publishing ($8.95, hardback/$4.95, paperback).

It is a slim volume, 126 pages of tightly-written, lucid descriptions of how heart disease and high blood pressure come about and quite specifically how they can be prevented, even reversed, by controlling "the factors in our lives which are responsible for the very high frequency of heart attack and stroke. The three most important ones are cigarette smoking, poorly controlled high blood pressure and bad eating habits."

As he describes it, his program "de-emphasizes excessive attention to drugs and surgery and puts more emphasis on more natural means of avoiding heart attack."

Mulcahy is unabashedly envious of the American heart foundations and speaks admiringly of the National Institutes of Health and their research and educational facilities. "Most European governments," he sighs, "have done nothing about prevention."

Ten years ago, he notes, America was highest in the Western world in incidence of heart disease. Today, with about a 25 percent decrease in the United States, the top-risk areas are Scotland and Northern Ireland, England, Wales and then Australia and New Zealand -- the English-speaking Western nations.

Mulchay also is frankly covetous of the resources and success of American anti-smoking campaigns. An ex-smoker himself, he shares the zeal of the converted and the book presents an awesome and graphic description of what is caused by or exacerbated by smoking ("coronary heart disease, stroke, vascular disease of the legs, chronic bronchitis, emphysema, respiratory failure and lung cancer") and those illnesses associated with smoking ("throat and bladder cancer, duodenal ulcer, chronic catarrh, sinusitis and dental decay").

He also documents in detail how the damage is done, in summary, by damaging the delicate inner lining of the bronchi as well as the mechanism designed to eliminate waste products; by injuring platelets in the blood; by increasing the tendency of blood to clot in vessels; by stimulating production -- which stress does, too -- of substances called catecholamines, which may cause heart irregularities; by stimulating chemicals which cause blood vessels to constrict; by blocking oxygen in the blood.

Exercise is his great love, "Not," he says, "because I think exercise per se will prevent heart attacks, but I advocate exercise, physical fitness and an active life because people who get interested in exercises and sports and physical fitness are much less dependent on habits like smoking, overeating, drinking too much and they tend to become low-risk cases without any effort."

The book contains tips, exercises, nutrition suggestions and calories counted in grams as well as ounces. It is -- as is he -- a charming and intelligent persuader.

Mulcahy is 58, and the father of six children now ranging in age from 16 to 24. He is trim and energetic and when he's not lecturing, writing, teaching or treating, he can most likelybe found jogging the streets of Dublin.