Redefining What We Call a ‘Heart Attack’

Americans soon will be having more heart attacks than ever before, but heart experts aren’t worried. In fact, they think the increase could save lives.

Cardiologists recently broadened the definition of a heart attack to include many cases of angina, chest pain caused by lack of blood to the heart. A diagnosis of a heart attack, they hope, will make people take their conditions more seriously.

Just the dreaded words “heart attack” could provoke the kind of diet, exercise and other lifestyle changes that are crucial to a heart patient’s recovery, doctors say.

“It could be a positive thing,” says Dr. Sidney Smith, a University of North Carolina cardiologist and former American Heart Assn. president. “Frequently, it’s hard to get patients to change behavior. If there has actually been damage to their heart, the ability to stop smoking and adhere to a low-cholesterol, low-fat diet, and make other changes may be greater.”

Darla Bonham, executive director of Mended Hearts, a support organization for people with heart disease, agrees that the words “heart attack” carry weight.

“For most people, having a heart attack is a life-changing experience,” she says.

But although the redefinition is intended to help people, it could cause many thousands of them grief. Patients labeled as having had a heart attack could see their health and life insurance premiums rise and could even be denied such things as a pilot’s license, according to presentations made at a 1999 conference debating the redefinition.

Police officers, firefighters and pilots could be especially affected because they may be restricted from doing some or all of their job, Bonham says.

“There are social implications to this change,” says Dr. Joseph Alpert, a University of Arizona cardiologist who helped write the new definition for the American College of Cardiology and its European counterpart. “It will require some educating to explain to people these are small [heart attacks]. It isn’t the end of the world if you get diagnosed. It’s just that we were just missing it before. We were calling it angina.”

The decision to change the definition was announced in a paper published this month in the Journal of the American College of Cardiology. The paper suggests that patients be given the diagnosis of “coronary artery disease with heart attack” to make sure they understand the need to address their underlying condition. People who have had a heart attack are four to six times more likely to experience sudden death from heart disease.

“Even when you have even a little heart attack, it means you are at higher risk for another event,” says Alpert. “The new definition means we can be a little more aggressive in dealing with these patients.”

The new definition could boost the number of U.S. heart attacks by 10% to 15%, he says. About 1.1 million Americans each year have a heart attack, according to statistics based on the old definition.

The new definition was prompted by growing enthusiasm for a revolutionary blood test that measures troponin, a heart protein that appears in the blood after a heart attack and that indicates damage to the heart. Discovered about 10 years ago, troponin is credited with greatly improving doctors’ ability to make accurate heart attack diagnoses.

For example, if a blood test is positive for troponin, people who have severe, stable or unstable angina will now be diagnosed as having had a heart attack.

Previously, doctors relied heavily on an electrocardiogram (ECG), in which sensor pads are placed on the body to detect the heart’s electrical impulses and translate them into wave patterns, says Smith. “We’ll see the biggest change from this new definition in a group of patients who don’t have the classic changes on their ECG but have damage on the biochemical markers that are obtained by sampling blood,” he says. “It will open up a whole new group there.”

The change will affect scientists, too. For example, it may confuse efforts to follow trends in disease rates. And the criteria for entering patients into clinical trials may change.

It will also be more difficult comparing studies in which different definitions of heart attack are used.

“There will have to be an asterisk next to the new statistics,” says Smith.