Acute Coronary Syndrome

So you’ve never heard of an acute coronary syndrome. But what aboutheart attack, or unstable angina? Those well-known conditions are both acute coronary syndromes, an umbrella term for situations where the blood supplied to the heart muscle is suddenly blocked.

“This is an absolute medical emergency. Something dramatic, right this minute is going on in the arteries that is hurting the blood flow to the heart,” said Ann Bolger, M.D., a cardiologist at San Francisco General Hospital and a member of the American Heart Association’s Council on Clinical Cardiology. 

The blockage can be sudden and complete, or it can come and go – clot, break open, then clot again. “In either case, the heart tissue is dying, even if it’s just a few cells or a whole big section of the heart,” Bolger said.

Doctors use the broad term regularly, but usually only among themselves and in the medical literature. “It’s like describing a North American state rather than just saying Texas,” Bolger said. “I don’t think too many doctors say, ‘You’re having an acute coronary syndrome.’ They say, ‘You’re having a heart attack.’”

What are the symptoms?
Chest pain or discomfort may immediately signal to you that something’s wrong with your heart. Other symptoms, however, may leave you unsure of what’s wrong. Take note of these common signs of an acute coronary syndrome:

• Chest pain or discomfort, which may involve pressure, tightness or fullness
• Pain or discomfort in one or both arms, the jaw, neck, back or stomach
• Shortness of breath
• Feeling dizzy or lightheaded
• Nausea
• Sweating

These symptoms should be taken seriously. If you experience chest pain or other symptoms, call 9-1-1 immediately. “People are in denial and they’re sitting there thinking, ‘This can’t really be happening to me,’” Bolger said. “We want them to feel entitled to call 9-1-1. They’re not being alarmist.”

Chest pain caused by acute coronary syndromes can come on suddenly, as is the case with a heart attack. Other times, the pain can be unpredictable or get worse even with rest, both hallmark symptoms of unstable angina. People who experience chronic chest pain resulting from years of cholesterol buildup in their arteries can develop an acute coronary syndrome if a blood clot forms on top of the plaque buildup.

How is it diagnosed and treated?
To determine what’s causing your symptoms, a doctor will take a careful medical history and give you a physical examination. If the doctor suspects an acute coronary syndrome, the following tests will be performed:

• A blood test can show evidence that heart cells are dying.
• An electrocardiogram (ECG or EKG) can diagnose an acute coronary syndrome by measuring the heart’s electrical activity.

If tests confirm blood flow to the heart has been blocked, doctors will work quickly to reopen the artery. “Minute by minute, the heart is accumulating irreversible damage. So time is myocardium – myocardium being the heart muscle itself,” Bolger said.

At San Francisco General Hospital, the goal is to have the artery reopened within an hour of the patient entering the hospital, Bolger said. Generally, patients do best when the artery is reopened within four hours of the first symptoms.

Treatment for acute coronary syndrome includes medicines and a procedure known as angioplasty, during which doctors inflate a small balloon to open the artery (View an illustration of coronary arteries). A stent, a wire mesh tube, may be permanently placed in the artery to keep it open. For hospitals not equipped to do angioplasty quickly, drugs may be used to dissolve blood clots, but more hospitals are making the procedure available in a timely manner, Bolger said.

Am I at risk?
Acute coronary syndromes, just like heart failure and stroke, are much more likely in people who have certain risk factors. These include:

• Smoking
• High blood pressure
• High blood cholesterol
• Diabetes
• Physical inactivity
• Being overweight or obese
• A family history of chest pain, heart disease or stroke

Your primary care doctor can help you understand your personal risk and what you can do about it. “[The physician] should also be the one to say, ‘By the way, if you ever have any of these symptoms, I want you to call 9-1-1,’” Bolger said. “If someone has told you that in advance, you’re much more likely to do it.”