- The Washington Times - Monday, March 20, 2000

The quest to conquer heart disease America's leading cause of death has gobbled up billions and billions of dollars and engaged countless researchers over 50 years. Still, there is no cure.

In fact, although the heart-disease death rate has dropped a stunning 50 percent since 1950, the National Heart, Lung, and Blood Institute reports "a slowing in the decline of the death rate for coronary heart disease."

The institute also notes in a progress report that, "Some cardiovascular conditions are increasing dramatically the prevalence of heart failure jumped from 2.2 percent of Americans age 60-69 in 1976-80 to 5.5 percent in 1988-91."

Additionally, the report states, "more Americans are overweight and less physically active than ever before two risk factors for heart disease."

"Heart disease" is the generic name for any of the many abnormal heart conditions that produce illness. Coronary heart disease refers to the main form of heart disease, which is caused by a narrowing of the arteries that channel blood to the heart. The institute's message is that the pool of candidates for that ailment is growing fast.

And that raises a question: Just where are we in battling this sickness, which currently affects 58 million people and kills some 953,000 each year an ailment that, put differently, affects more people than live in California, Florida and Michigan combined and that annually snuffs out 45,000 more people than inhabit Baltimore and Richmond?

The answer, say scientists, is that we're making progress, and a cure may even be in sight.

"If you say 'cure,' you mean you treat the disease, and afterward, you find no evidence of it. That's still a goal. We're not there. But it is possible because of early recognition and early and appropriate treatment."

The prognosis comes from Dr. George Sopko, a cardiologist at the National Institutes of Health. With other specialists, he stresses the great strides made in "curing by prevention" the process of reducing deaths and alleviating symptoms by educating "the public, patients, and health care professionals," as the heart institute puts it.

Indeed, the institute report states that, "One of the greatest health advances over the past 50 years has been a better understanding of factors that increase a person's risk of heart disease."

The much publicized factors are smoking, high blood pressure, high blood cholesterol, overweight, lack of exercise and diabetes. All those can be controlled, and some can be eliminated.

That leaves two less-often-noted and "uncontrollable" factors: "heredity," meaning a family history of heart disease, and "age," or living longer than 45 years if you are a man and 55 if a woman.

Yet a half-century of heart research has achieved far more than cataloging risk factors and educating the public. It has fundamentally changed the medical delivery system. Dr. Eugene Passamani, director of cardiology at Bethesda's Suburban Hospital gives an example:

"In 1950 the emergency room as we know it didn't exist. It was staffed only by nurses. There was no emergency medicine as we know it, no 911 number to call, no special cardiac unit. A patient experiencing chest pains would phone his doctor.

"The doctor would tell him to meet him at the hospital. Then the doctor would try to get away from his office.

"At the ER an electrocardiogram would be done and the diagnosis made. The patient would be put in bed to rest and would stay there for six to eight weeks. For the first three weeks, he would be limited to bed. If the patient's heart began to beat irregularly, he'd die. There was no such thing as CPR. No electrical treatment to stimulate the heart.

"If he was lucky enough to survive the hospital stay, the doctor would say, 'Put your affairs in order and quit work.' He would make the patient a cripple."

Under those conditions in the 1950s, "about 30 percent of the heart-attack victims who made it to the hospital were fatals. Currently 7 percent or fewer die," says Dr. Sopko.

Researchers long ago discovered that heart-attack victims who receive treatment within three hours typically have a 90 percent chance of survival and recovery. So the medical system is geared to providing quick help.

Today a patient "who knows enough to recognize the symptoms" will dial 911, says Dr. Passamani. Then an ambulance is dispatched. Emergency medics arrive, immediately take an electrocardiogram (EKG) and phone the results to the hospital "receiving unit" so the ER can prepare for the patient's arrival.

Otherwise, the medics may first hustle the patient into the ambulance and take the EKG while racing to the hospital. There an emergency room physician and nurses meet the patient, check the EKG and start administering clot-busting drugs. Depending on the diagnosis, they may immediately perform angioplasty.

Angioplasty involves running a catheter or slender tube containing a tiny, deflated balloon through an artery to the site of the troublesome blockage. There the balloon is inflated. The balloon pushes aside the obstruction as it inflates and "interrupts the attack."

Four days after arriving the patient will be released from the hospital.

"The patient will be rapidly advanced in activity. A month to six weeks later, he will be put into an exercise program, and, if he's doing non-strenuous work like a doctor or reporter, he'll be back at work," says Dr. Passamani.

The patient would not, however, be cured. He would be taking drugs and dieting and exercising to prevent the possibility that his arteries will clog again.

"In 50 years we've created an entirely new universe," says Dr. Passamani

An array of drugs discovered since the 1950s can dissolve blockages, largely prevent the artery-clogging material called plaque from massing, depress blood pressure, lower cholesterol, reduce heart pain, control heart beat and much more.

Heart surgeons now routinely transplant sections of artery or vein from another part of the body to "bypass" clogged arteries. They can strengthen weakened artery sections with tubelike wire-mesh "stents," implant heart pacers to control irregular heart beat and replace fatally weakened hearts.

Yet none of the drugs or procedures will eradicate the disease. The hope of doing that lies in current and promising research.

Scientists know, for instance, that the risk factors noted above cause just half the heart disease afflicting Americans. So they're struggling to find the mysterious causes of the other half.

They're becoming convinced that bacteria may be a culprit along with high levels of an amino acid called homocysteine (pronounced homo-SIS-teen). If they're correct, there is hope of someday thwarting the bacteria with drugs and also of countering the effects of homocysteine.

Scientists also are beginning to identify certain genes that cause heart disease, and it is expected that the gene's effects can be negated. That would enable physicians to control that uncontrollable risk factor called heredity.

The American Heart Association reports researchers have detected in youngsters with "early onset high blood pressure" a mutated gene that affects the body's ability to regulate salt. As a result, the child's blood pressure rises and heart disease develops.

Investigators also have noted that other molecular problems so weaken the heart that it cannot pump sufficient amounts of blood through the body. And they have located the genes that when mutated or missing cause congenital heart defects in infants.

Searches are under way to find therapies for correcting all those genetic flaws.

Besides, a study reported in February relates that two French physicians have discovered "a specific cholesterol-clearing gene" that in animals reduces high cholesterol and eliminates fatty substances similar to those that block humans' arteries.

And in another approach to erasing blockages, scientists are developing a process called "angiogenesis," which means "vessel rebirth." In angiogenesis new blood vessels naturally grow from old ones but not always when and where needed. Consequently researchers looked for and found substances that promote angiogenesis.

They have injected the substance into cardiovascular patients with blocked leg vessels and dangerously diminished blood flow. The blood vessels sprouted new vessels and restored the blood flow. So it is hoped similar techniques can be used to grow vessels that will detour around blocked heart arteries.

Remarkably, scientists also have begun growing animal heart valves in the laboratory to implant in humans. Heart valves control the flow of blood from the heart. When they malfunction the result is serious disability or death.

However, animal tests indicate that valves grown from an intended recipient's cells are likely to be tolerated better and work more efficiently than the mechanical valves and the transplanted pig valves now being used. Attempts to grow and implant human heart valves are on the horizon.

So goes the quest for cures that may erase heart disease. The American Heart Association calculates that when that happens, life expectancy in the United States will rise by nearly seven years, millions of people will be spared searing pain and the nation will be $300 billion richer.

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