At the emergency room or chest pain center — some large hospitals designate areas just for the evaluation of chest pain — you'll probably have your blood pressure, pulse and temperature checked right away. In addition, the doctor will ask you questions about your chest pain: Where is the pain located? How would you describe the pain? Do you have other signs and symptoms along with the pain?

Chest pain doesn't always signal a heart attack. But that's what emergency room doctors will test for first because it's potentially the most immediate threat to your life. They may also check for life-threatening lung conditions, such as pulmonary embolism or a collapsed lung (pneumothorax), that can cause chest pain.

Tests you may have to determine the cause of your chest pain include:

• Electrocardiogram (ECG). This test can help doctors diagnose a heart attack as well as other heart problems. It records the electrical activity of your heart through electrodes attached to your skin. Impulses are recorded as waves displayed on a monitor or printed on paper. Because injured heart muscle doesn't conduct electrical impulses normally, the ECG may show that a heart attack has occurred or is in progress.

• Stress tests. These measure how your heart and blood vessels respond to exertion, which may indicate if your pain is related to your heart. There are many kinds of stress tests. You may be asked to walk on a treadmill or pedal a stationary bike while hooked to an ECG. Or you may be given a drug intravenously to stimulate your heart in a way similar to exercise. Stress tests may be combined with imaging scans of the heart.

• Blood tests. Your doctor may order blood tests to check for increased levels of certain enzymes normally found in heart muscle. Damage to heart cells from a heart attack may allow these enzymes to leak, over a period of hours, into your blood.

• Chest X-ray. An X-ray of your chest allows doctors to check the condition of your lungs and the size and shape of your heart and major blood vessels. Doctors also can use a chest X-ray to check for tumors in the chest.

• Nuclear scan. This test helps doctors diagnose cardiac causes of chest pain, such as a narrowed heart artery. Trace amounts of radioactive material, such as thallium, are injected into your bloodstream. Special cameras can detect the radioactive material as it flows through your heart and lungs.

• Coronary catheterization (angiogram). This test helps doctors identify individual arteries to your heart that are narrowed or blocked. A liquid dye is injected into the arteries of your heart through a catheter — a long, thin tube that's fed through an artery, usually in your leg, to arteries in your heart. As the dye fills your arteries, they become visible on X-ray and video.

• Electron beam computerized tomography (EBCT). This procedure, also called an ultrafast CT scan, scans your arteries for signs of calcium, which indicates that fatty deposits along with calcium may be accumulating and blocking arteries supplying your heart.

• Echocardiogram. An echocardiogram uses sound waves to produce a video image of your heart. This image can help doctors identify heart problems.

• Endoscopy. In this test a thin, flexible instrument attached to a camera is passed down your throat, allowing doctors to view your esophagus and stomach and check for gastroesophageal problems that can cause chest pain.

Many types of chest pain may at first seem related to heart problems. But often, after careful evaluation, doctors can distinguish the symptoms of noncardiac chest pain from the pain caused by a heart condition.