American College of Cardiology

Fifty Years of Advances
Looking Beyond the Millennium
A Heart-Healthy America

Those who remember when Joe DiMaggio and his Bronx Bombers were the talk of baseball may also recall what a diagnosis of heart disease meant at the time. In those days, cardiologists could do little more than check a patient’s heartbeat to detect a problem. Using only their senses, taking a thorough history, and drawing upon a limited number of tools—mainly the stethoscope and the electrocardiograph—cardiologists fought to save their patients’ lives. But the challenge was daunting. In 1950, heart disease accounted for more than half of all deaths in the United States.

At the time, doctors did not understand the causes of most heart diseases. Physicians didn’t know what triggered heart attacks and other sudden heart problems, and they couldn’t determine who was likely to be struck down.

But with the creation of the National Heart Institute (now the National Heart, Lung, and Blood Institute) in 1948, the nation, which had just returned from one war, joined with the field of cardiology to wage another. In the intervening years, both the "Why?" and the "Who?" would be answered thanks to an incredible body of research conducted by cardiovascular specialists over the past 50 years.

Cardiovascular specialists have made these advances by looking at the very small or microscopic pieces of the puzzle, such as tissues and cells, as well as the very large or macroscopic, such as studying where diseases come from and how they spread (epidemiology).

Fifty Years of Advances
Before effective diagnostic tests and treatments could be developed, cardiovascular specialists had to understand how cardiovascular disease develops and progresses (pathophysiology). There were tremendous strides made in the last 50 years, stimulated in large part by the research support of the National Institutes of Health, the National Heart, Lung, and Blood Institute, and the American Heart Association. One by one, dramatic and effective new technologies and pharmaceuticals emerged.

The fruits of this research have played a major role in the 50 percent decline in the number of deaths from cardiovascular disease since 1965. Furthermore, because the modern treatment of cardiovascular disease saves lives and returns patients to work, it has proven to be highly cost-effective—an important consideration for the next century.

Looking Beyond the Millennium
So where will the next century lead us? Most likely, experts say, in the same two dimensions—the very small and the very large—only much farther.

Graph 2. National Center for Health Statistics. National Vital Statistics Reports. 1967-1995 United States Department of Health and Human Services. Morlyman et al. Cardiovascular Diseases in the United States. Cambridge, MA: Harvard University Press; 1971

In the realm of the microscopic, scientists now know more about the molecular basis of heart disease and that understanding has brought about a number of novel therapeutic approaches. For example, doctors now have new ways to identify dangerous outcroppings in the arteries of fat deposits called atherosclerotic plaques. These fragile plaques can rupture, cause a blood clot, and lead to a heart attack. Finding them early saves lives.

"We’re likely to see in the years to come techniques that will allow us to assess the amount of blockage and the potential for future trouble," said Spencer B. King, III, MD, 1998-1999 president of the American College of Cardiology and professor of medicine at Emory University School of Medicine. "Expect also to see major refinements in angioplasty, coronary stents, plaque removal, and other ways to prevent arterial disease from progressing."

Learning how to manipulate genes may also help scientists understand what causes high blood pressure, high cholesterol levels, and heart failure. Researchers already know that some diseases such as hypertrophic cardiomyopathy are associated with genetic mutation. Scientists are working to develop ways to pinpoint and repair the faulty genes. Other researchers are looking for ways to enable patients who have advanced, inoperable heart disease—caused by blocked arteries—to grow new blood vessels and to help survivors of heart attacks restore their damaged heart muscles.

Surgical techniques, too, will become more sophisticated. Dr. King expects to see new methods to perform coronary artery bypass graft operations and less invasive ways to repair heart valves and treat arrhythmias. Novel uses of catheters are on the horizon. Catheters may be used to open pathways that have become blocked, Dr. King noted, as well as to repair encrusted and degenerated heart bypasses. The application of diagnostic technologies such as magnetic resonance imaging (MRI) to cardiovascular conditions will permit early identification of people who are at risk for serious heart problems.

Looking to the macroscopic, epidemiologists also will examine a number of risk factors for heart disease that are emerging in the population as a whole. Among the most prominent are—

• insulin resistance, which has been associated with vascular disease in diabetic patients;
• estrogen deficiency, which has been associated with higher rates of heart disease in postmenopausal women;
• homocysteine, an amino acid that can damage the walls of blood vessels, leading to atherosclerosis;
• C-reactive protein and other markers of inflammation that may help identify individuals at risk of unstable angina or acute myocardial infarction (heart attack); and
• Chlamydia pneumoniae infection, which has been linked to atherosclerosis and the formation of high-risk plaques.

A Heart-Healthy America
"Based on the American Heart Association strategic goals, by the year 2008, we hope to have further decreased by 25 percent the incidence and mortality related to coronary artery disease and stroke. We also hope to decrease by 25 percent the conventional risk factors that affect patients," said Valentin Fuster, MD, PhD, president of the American Heart Association. "We will approach these goals in two ways: first with an aggressive program of education, advocacy, and communication about prevention; second with an aggressive effort to increase research."

Graph 3. National Center for Health Statistics. National Vital Statistics Reports. 1996; Vol. 47; No.9. United States Department of Health and Human Services.

So the war on cardiovascular disease continues its advance on dual fronts—at the molecular level and population-wide. "You might say that in the future we’re going to build on our base of knowledge," Dr. King said. "The 21st century should be a fruitful period in which we continue to develop new strategies and techniques to attack the problems we’ve spent the past 50 years identifying."