WHEN 19TH-CENTURY audiences waited eagerly for the next burst of genius from the likes of Byron, Dumas and Puccini, they were unaware that they were participating in an enormous exercise in medical epidemiology. Rather, they clebrated such authors and composers because their works were a distillation of life, and an overwhelming fact of the lives depicted by artists in the last century was the slow, painful wasting away of talented, artistically sensitive young men and women. These charming youths lived poetic, bohemian lives. They died romantic deaths.

The truth is they died of pulmonary tuberculosis. So many fictional heroes and heroines -- as well as their authors -- died of TB that disease and creativity became almost synonymous. The poetic look that many Victorians deliberately cultivated was one of languorous illness. Gautier once proclaimed that "no lyric poet could weigh more than 98 pounds."

Today, similarly, we live conditioned by a great epidemic, one unknown and undreamed of at the turn of the century: the sudden blocking one of the arteries bringing blood to the heart itself (coronary occlusion), causing acute gangrene of heart muscle (myocardial infarction). In short, the heart attack. g

The epidemic of coronary-artery disease that began sometime in the first decades of this century (and that may now be starting its decline) has affected 20th-century life in so profound a way that only future historians will be able to gauge its mark.

It is hard for most people to believe that we have only recently arrived at our understanding and definition of the heart attack. Angina pectoris, the transient cramping pain caused by temporary lack of blood supply to the heart, was described by William Heberden in 1768, but he had no idea that it was related to the heart. In the next two centuries, "apoplexy" was recognized as a cause of death (the great physician John Hunter once said, "My life is in the hands of any rascal who chooses to annoy and tease me"), but it was confused with what today we call stroke.

Not until the last decade of the 19th century was the relationship between heart attacks, angina pectories and the coronary arteries described, and it wasn't until 1910 that Dr. James Herrick of Chicago described the simple fact that every school kid knows today: One can experience coronary occlusion -- the complete obstruction of a coronary artery -- and live to tell the tale. And experience it again. And again.

Medical historians debate the reasons for the delayed identification of coronary thrombisis. Some feel that it was misdiagnosed; some feel that it was undiagnosed; some feel that it is a completely new disease. Almost all agree, however, that the great physicians of the last century weren't that obtuse; the reason they didn't diagnose coronary disease was that there wasn't that much of it around. Similarly, one can argue about the cause -- whether it is our diet (a Victorian epiure's dream now delivered to 90 percent of the population) or cigarette smoking or stress or the absence of the competing infectious diseases that once wiped out many people much earlier.

These considerations are unimportant to the average North American. For us, death by heart attack is a part of life.

The term heart attack permeates our culture. We use it casually or fearfully, seriously or jokingly, knowingly or ignorantly, but we use it all the time. It and the disease it represents play a hidden part in our lives, the way the now-vanished term consumption and the disease it represented -- tuberculosis -- did in the last century. And because of the unique clinical aspects of coronary heart disease, the effect it has produced on our society, our literature, our commerce and our living patterns is also unique.

One might argue that cancer is an equally dreaded disease and has had just as profound an effect on our society. As Susan Sontag points out in her brilliant "Illness as Metaphor," our society does have its cancerphobes, such as Norman Mailer, whose thoughts and images are haunted by malignancy. Yet, as often as cancer is evoked metaphorically ("We have a cancer [Watergate] within -- close to the presidency," John Dean pleaded with his boss), it has not had the dramatic social effect of coronary disease.

For one thing, cancer has always been with us; medically and intellectually, it has affected societies since antiquity. There may have been a true increase in the incidence of cancer in recent years, even when statistics are adjusted to reflect the fact that people in the past died of infections before they ever got old enough to develop cancer, but if so, the increase is not of epidemic proportions.

Although statisticians argue about possible increases in the cancer rate, there is no disagreement that epidemic coronary-artery disease (which emerged, almost de novo , 70 years ago) is a 20th-century phenomenon.

Coronary disease is not only the most common cause of death in this country, it is by far the most common. More than 800,000 men and women die of heart attacks each year. In contrast, cancer of the cervix, which the Pap smear helps to detect and prevent, causes approximately 7,200 deaths yearly. Cancer of the breast causes 37,000 deaths, and lung cancer causes 105,000. The annual death rate per 100,000 Americans for cancer of all types is 188. For heart disease it is 332.3. Thus, while we all fear both cancer and heart attack to some extent, we are much more likely to have personal contact with someone with heart disease.

It is also clearly important that, under the age of 50, men have a heart-attack incidence three to four times as high as that of women the same age (the rates for men and women grow closer together the older we get). Men get heart attacks, but their wives and daughters are not spared anxiety. And it is men under 50, the most dramatic victims of this modern epidemic, who in the past have been the communicators in our society -- reporters, authors, editors screenwriters and columists. Anxiety affecting them is, by definition, most likely to be transmitted to the rest of the country; and so it has been with coronary phobia.

We take for granted not only the ubiquitous influence of coronary disease on our everyday life but also the unique medical character of the disease itself. Never before, however, has humanity been beset with a disease like coronary atherosclerosis -- a disease whose very first symptom may, for many, be sudden death; a disease that, for millions, shows its hand in subtle but terrifyingly regular attacks of squeezing chest pain during exercise, emotion, or even rest; a disease in which recovery from a massive heart attack by be followed by a long symptom-free period, only to be ended by another dramatic attack.

It is capricious, sudden confrontation with death that has stamped coronary disease on the consciousness of western man. The great infectious plagues of the past colored the art and literature of medieval and preindustrial Europe because whole cities would be decimated in a matter of days or weeks. Death was rapid but communal. The indolent nature of hte tuberculosis bacillus gives its victims months or years to reflect upon life and approaching death. Syphilis often does not kill for decades. Cancer, however much it is feared, is not associated with sudden death.

Nothing shows more completely how our society is permeated with this sense of doom than an examination of how our children think. In "The Bad News Bears" the fat catcher refuses to run laps: "I'm not going to get a heart attach," he says. The kids in the audience laugh knowingly. Sally expresses her doubts about Santa Claus to Charlie Brown: "I can't believe he can crawl up and down all those chimneys without losing a little weight. Do you know what's gonna happen? One of these times he gonna have a coronary right in some poor little kid's living room."

Everyone has heard the words: "Don't work so hard. You're going to have a heart attack." In this formulation we see one of the main themes of our cultural obsession with heart disease. More and more we believe that hard work -- especially hard mental work but also hard physical work -- can produce a block to the coronary arteries. Try too hard, worry too much, lift too much and bim-bam ! you're dead.

While upper-middle-class America cherishes a mystic belief in the ability of running, jogging, or trudging to protect the coronary arteries, blue-collar America still thinks that too much exercise is harmful. At least, compensation programs for firemen, policemen and foremen regularly cite the harmful effects of carrying, lifting or worrying as contributing to their members' heart attacks. All classes of Americans believe that heart attacks can be caused by stress -- though the epidemiologic evidence for this is perhaps the weakest of any of the generally recognized links to coronary disease.

An equally pervasive and perhaps even more primitive association is the growing notion that any kind of excitement -- including pleasurable excitement -- can provoke a coronary. Thus, the more we are enjoying ourselves, the closer we are to death. The unique nature of coronary disease makes this appear reasonable. Death from cancer is not associated with enjoyment, and although TB is said to induce exalted feelings, it is not a disease of sudden death. We accept without thinking about it a sportswriter's characterization of 1979's second Redskins-Dallas football game as "a coronary classic."

Our grandparents would have been baffled, but today, exciting or close games are invariably described in clinical terms. It is as though one were attending a conference of cardiologists: "a heartstopper of a game," "brought local fans to the brink of heart attacks" are some of the phrases use by sportswriters.

Sex, too, is considered dangerous. Gore Vidal, the universal expert, tells Women's Wear Daily: "The tyranny of the feminine orgasm is a bit of madness that has come of feminist psychology. It is supposed to be a woman's due, even if the man goes into cardiac occlusion giving it to her. Nothing is anybody's due."

It is no secret, however, that many men are concerned about getting cardiac occlusion while trying to achieve male orgasm. Ann Landers once printed a matter-of-fact set of guidelines for the woman in whose apartment a nonspouse male was apt to die.

Eating is fraught with peril. Quite simply, death is part of every meal. When a middle-aged American male free-associates about milk, he doesn't visualize rosy-cheeked dairymaids and contented cows; he thinks of cholesterol -- and death. No one thinks it unusual that a reporter for The Washington Post should begin an interview with a visiting author in this way: "James Roosevelt . . . is a man of 72 in rosy health who fears neither man nor beast nor cholesterol . . ." The reference to cholesterol is clarified further in the article, in which Roosevelt is described at breakfast as "raising his eyes from a ton of scrambled eggs and bacon."

As the 24-year-old seamstress dying ethereally of tuberculosis was a stock figure of 19th-century literature (because she had millions of real-life counterparts), so the 42-year-old man tumbling dead at the dinner table is a stock figure of the 20th-century imagination (because we all know of actual cases). But you can't get a good novel out of a heart attack.

One of the reasons for the failure of the 20th century to produce novelists who are both great and popular is the lack of a sense of epic sweep in our lives, and one reason we lack the sense of destiny's working itself out over a period of years is the lurking sense of sudden, arbitary death.

As a cardiologist and a writer, I have enjoyed occasional meetings with full-time novelists in the waiting rooms of TV talk shows. Before I could swap shoptalk and even a few hints about taxes and the future of the first-person novel, I would invariably be asked my personal feelings about HDL [high-density lipoprotein] cholesterol and the reliability of the treadmill-exercise test. Our male authors are haunted by death, and it is a very specific kind of death.

The physician and author William Carlos Williams suffered his first heart attack at 65, during one of his most productive literary periods. His last 15 years were clouded by angina. Biographer Reed Whittemore writes: "How heavily the heart trouble lay upon him in the late Forties was especially evident in probably the best play he ever wrote, 'A Dream of Love' . . . In the final version of the play the doctor hero . . . was taken with a heart seizure while making love to a certain Dottie in a New York hotel room -- and died on the spot."

Our daily lives, of course, are marked by coronary phobia much more directly than is our literature. As soon as women began to enter the professions and executive positions in larger numbers, articles began to appear about the possibility of an increasing rate of coronary disease in younger females. Male physicians and physiologists ruminated, not without a a certain malice, on the risk an executive woman runs. At best, there was a sense of "Welcome to the club"; at worst, a hint of "Serves you right." Women do develop the "Type A," or coronary-prone, personality, but so far the Framingham Heart Study shows that women executives do not have a higher coronary rate than housewives do.

Men's working lives are already shaped by coronary disease. Dr. John Egerton, a Texas GP, writes in Medical Economics, "Each time my home phone rings or my beeper sounds, I get the feeling that my coronary arteries have narrowed a bit more." Menachem Begin became so upset by criticisms of his government that he developed palpitations and rushed himself to the hospital.

The treat of a heart attack is ever present. Companies teach their employes CPR (cardiopulmonary resuscitation) and encourage them to stop smoking. This on-the-job prevention of death has a more powerful second message, however. To the extent that the middle-age crisis really exists and is not merely part of the continual reshaping of one's goals since childhood, it is often the result of a brush with a sudden death -- one's own or a friend's.

Part of our unwillingness to stay 50 years in the same job or 25 years with the same company stems, I am convinced, from the popular conviction (not supported by many cardiologists) that stress causes coronary death. Male executives and professionals who drop out to run yacht-charter services in the Bahamas or restaurants in Sausalito may be implelled by visions of sailing nymphets or restaurant groupies; but time after time, interviews with such paragons ("I'm 20 pounds lighter, I've kicked cigarettes") make some mention of heart attacks.

For each man who drops out totally, there are large numbers who have backed off, who won't put in the extra days on the road, who won't work weekends, who are constent to accept less prestigious positions. For all of them, a heart attack is a rationalization for accepting second place; for some, it's a sincere reason. In many hospital gift shops one can purchase a get-well card with the catchy message, "A heart attack is God's advice to slow down."

Our obsession with fitness is linked to the epidemic of heart attacks: it's no coincidence that the people who exercise by far the most often -- middle-class white males -- are the ones most threatened by coronary disease. This newspaper ran a long article about postcoronary exercise programs in its sports section some time ago. Heart attack sell fitness, cardiac rehabilitation ends up on the sports page, and no one thinks it is the least unusual.

Coronary disease is a lonely illness. Unlike bubonic plague, it does not strike your family and your entire community at the same moment it hits you. Unlike epilepsy or kidney failure, it is not the kind of disease that welds its victims into a loybbying alliance such as the Epilepsy Foundation of America. People with severe epilepsy or kidney failure live every moment affected in some measure by their symptoms or medicines. The patient who has coronary disease usually feels fine 99 percent of the time. It is the 1 percent that worries him.

Victims of our last great plague, tuberculosis, were physically segregated from the rest of society. They were quarantined in their rooms, or they were exciled to sanatoriums or to distant regions reputed to be good for the tubercular. The history of Arizona and Colorado is in part the history of the "lungers" who went west for their health. Coronary patients, on the other hand, are with us but not always of us. No matter how healthy they seem, they carry with them a special knowledge that engenders special fears.

Patients vary in their response to a brush with death. In some, a coronary event engenders a pulling away from life and, especially, from conflict. Such people award themselves a Purple Heart and retire, either figuratively or literally, from combat. For others, such as Lyndon Johnson, a heart attack means only a stepup in their already hectic lives.

It is a truism that the hectic pace of the 20th century has helped intensify the plague of coronary disease. We can now see that the plague of coronary disease has helped speed up the 20th century. We cannot allow ourselves long novels, long vacations, long careers, because we sense that we will be cut off in our prime. We "only go around once"; we "go for the gusto"; we are self-absorbed jogging masochists and self-enamored sexual hedonists because we are immersed in a popular culture that tells us -- not without reason -- that our hearts may rise up and attack at any moment.

The impact left by the plague of coronary disease on western civilization will, like the stunting of a tree's growth during a drought, become most apparent only when the epidemic is over.

There is now good evidence to suggest that the epidemic peaked in the late 1960s and is -- very slowly -- beginning to recede. Decreased smoking, better diets, better treatment of high blood pressure and more exercise all appear to have played some part in the decline in new heart attacks. Coronary narrowing during midlife is aberrant, a disease that should be as rare as baldness in children.

We will know that the plague has passed only at some future date, when a 10-year-old kid will turn from an old sports book and ask, "Dad, what's a coronary classic?"