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Quick Facts

Stress Testing


The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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What is a stress test?

A stress test lets doctors see how your heart works when it’s under stress, such as when you exercise. Many heart problems are easier for your doctor to find when your heart is working hard.

Why would I need a stress test?

Most often, you'd have a stress test if you're having chest pain. You might also need a stress test if you have a heart disorder and your doctor wants to see if it's getting worse.

How is a stress test done?

  • Small, round sensors (electrodes) are placed on your arms, legs, and chest to measure your heart’s electrical currents (called an electrocardiogram, or ECG)

  • You'll wear a blood pressure cuff on your arm

  • You'll walk on a treadmill or pedal on an exercise bike, picking up speed over time

  • As you exercise, doctors will watch your ECG and check your blood pressure often

  • If you can't exercise enough to do the test, doctors will give you a medicine to make your heart beat faster and stronger

Doctors will stop the test when:

  • Your heart rate nears the maximum recommended rate for your age

  • Your symptoms get too uncomfortable — you may have chest pain or feel like you can’t catch your breath

  • Your ECG or blood pressure readings show something abnormal

Sometimes instead of having an ECG during the stress test, you may have echocardiography or radionuclide imaging. These tests also let your doctor see how your heart reacts to stress. These tests are more accurate but more expensive.

Are there any side effects to a stress test?

Usually you'll exercise hard enough to feel strain and puff for breath. If you have a heart problem, you might feel chest pain or become aware of your heart beats during the test. Although rare, you could have a heart attack during the test. But your doctor will monitor you during the test to be ready for any problems.

What can my doctor learn from the stress test?

Stress tests help doctors:

  • Find signs of coronary artery disease, which is when you have too little blood flow to your heart

  • Figure out if you have a heart problem or lung problem, or if you’re just out of shape

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