Diagnosing Heart Disease

Content provided by the Faculty of the Harvard Medical School
Excerpted from a Harvard Special Health Report

Doctors use a variety of techniques to diagnose heart disease. They range from tried-and-true standards like taking a medical history, performing a physical exam, and ordering an electrocardiogram (ECG) to high-tech strategies such as nuclear imaging and computed tomography (CT) scanning or invasive tests such as coronary angiography. So what tests are best? The answer depends on your condition and your doctor's level of concern. If you have mild, stable, or atypical symptoms (for instance, fleeting episodes of stabbing pain), an experienced clinician might not go further than a history, examination, and ECG. On the other hand, if your symptoms are threatening (for example, a squeezing sensation in your chest, with breathlessness when walking more than a few yards and an abnormal ECG), your doctor might skip the preliminaries and go straight to an angiogram. In practice, most people fall between these two extremes, and they often benefit from a stepwise approach that begins with easy tests, followed by more sophisticated tests as needed, until the diagnosis becomes clear.

Your medical history

By far, the most important "test" in the diagnosis of coronary artery disease is a detailed conversation between you and your doctor. Your medical history — that is, your description of your medical background and symptoms — usually provides enough information for a physician to predict the general likelihood of coronary artery disease. The doctor should ask about such things as smoking, diet, and exercise; whether your parents or other family members have had heart problems; and whether you have a history of other medical problems, such as hypertension, high cholesterol levels, or diabetes.

Chest pain

As part of taking your medical history, the doctor will ask about chest pain in an effort to distinguish angina (the pain that occurs when the heart muscle is not getting enough blood through the coronary arteries) from a variety of other types of chest discomfort. Angina is the most common symptom of coronary artery disease.

Angina usually has certain characteristics. Many people describe it as a pressure, heaviness, squeezing, or tightness in the chest. Others complain of burning or aching. Relatively few people describe the pain as sharp or stabbing. The symptom can be almost anywhere in the chest, but typically it feels like a deep central discomfort behind the breastbone. Many people with angina clench their fists in front of their chests when groping for words to describe their chest pain. Angina can be triggered by a number of different things (see "Common angina triggers," below). People often report that the discomfort spreads to the shoulders, arms, neck, or jaw, and that it is accompanied by shortness of breath or sweating. Doctors call this pattern of pain "radiation."

Chest discomfort is unlikely to be angina if it is very brief (comes and goes in a few seconds), sharp, or stabbing. Similarly, pain that's limited to a small area (within a couple of inches) is probably not from the heart. For example, a pain that feels like a pencil being poked into the chest for an instant is likely to be a muscle spasm, not angina.

If the diagnosis is angina, the next step is to distinguish between stable and unstable angina.

Stable angina. Chest pain that typically lasts one to five minutes and goes away quickly when you rest or take medication is probably stable angina. This is a chronic condition and typically occurs in response to specific triggers, such as physical exertion, emotional stress, exposure to cold, or sexual activity. Stable angina is caused by plaque that partially obstructs blood flow. The condition requires medical treatment, but it is not a medical emergency.

Unstable angina. Chest pain that builds in intensity, lasts several minutes to hours, occurs or continues even while resting, and does not respond to medication may be unstable angina — a condition that is much more dangerous than stable angina. Both heart attacks and unstable angina occur when a plaque develops a tear or breaks, and both are classified as acute coronary syndromes, requiring immediate medical attention. (The difference between the two is one of degree: in unstable angina, the artery is partially blocked — although a full blockage could develop. In a heart attack, the artery is completely blocked.)

Other causes of chest pain. Of course, the heart isn't the only organ in the chest, and other medical problems can cause chest discomfort. For example, lung conditions such as pneumonia or blood clots in the vessels supplying the lungs tend to cause shortness of breath and sharp pains that intensify with a deep breath. Inflammation of the tissues around the heart (pericarditis) can cause a sharp pain that often worsens when you lie down. Arthritis and various injuries to the bones and tissues in the wall of the chest can mimic heart attacks. A condition called costochondritis (inflammation in the chest wall between the ribs and the breastbone) can also trigger pain that's often mistaken for a heart attack. The stabbing, aching pain may be caused by trauma or an overuse injury, or it may accompany arthritis.

Sometimes the problem originates in the gastrointestinal system. Chest discomfort can result when acid from the stomach flows up into the esophagus, causing heartburn (also called acid reflux) or when it causes damage to the stomach wall (as in the case of ulcer or gastritis). In addition, gallstones can occasionally cause chest discomfort very similar to angina.

Common Angina Triggers

  • Walking briskly outside on a cold, windy, or humid day

  • Hurrying with a heavy load

  • Exerting after a heavy meal

  • Working under a deadline

  • Speaking in public

  • Engaging in sexual activity

  • Being worried, tense, or angry

Other symptoms

Women are much less likely than men to experience chest discomfort either before or during a heart attack. Instead, they are much more likely to report unusual fatigue, shortness of breath, sleep disturbance, and weakness. Whether you are a man or a woman, it is important to pay attention to any unusual symptoms that develop, and talk to your doctor about them.

Your Guide to Heart Disease

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