A cardiac stress test helps doctors see how well your heart can cope during exercise, when the body's need for oxygen puts extra demands on the heart. Other names for this test are: graded exercise test, exercise tolerance test, exercise stress test, or exercise electrocardiography (e-LEK-tro-KAR-dee-AH-gruh-fee).

Reasons For the Test

Doctors order cardiac stress tests for a variety of purposes. The test helps them:

	Determine whether coronary arteries are clogged.
	Find the cause of chest pain.
	Assess the heart's capability after a heart attack or heart surgery.
	Discover heart disease.
	Set limits on your exercise.
	Detect extra heartbeats (also called arrhythmias [ah-RITH-me-uhs]), during exercise.
	Judge a medicine's capacity to control chest pain or extra beats during exercise.

Risks

Do not eat, drink alcohol, or smoke for 4 hours before the test.

Wear loose clothes suitable for exercise, such as lightweight pants or shorts and a shirt. Wear socks and footwear with rubber soles, such as walking, jogging, or tennis shoes.

	Taking Vital Signs: These include your temperature, blood pressure, pulse (counting your heartbeats), and respirations (counting your breaths). A stethoscope is used to listen to your heart and lungs. Your blood pressure is taken by wrapping a cuff around your arm. The staff will take your vital signs before you begin exercising, several times during the test, and after you finish.
	Electrocardiogram (EKG): While you exercise, a number of sticky pads called electrodes will connect you to a machine that makes tracings of the activity in different parts of your heart. You may also be hooked up to a heart monitor, which traces the heartbeat on a TV-like screen.

	You will be asked to take off your shirt. Women need not remove their bra, and can wear a gown if they wish. To help the electrodes stick to the skin, hair on parts of your chest or back may need to be shaved. These areas will also be cleansed to remove natural oils. Once the electrodes are in place, you will not feel any electric current from them, although the skin underneath them may itch.
	You'll be asked to exercise on a stationary bicycle, a motorized treadmill (a machine on which you can walk or jog), or an arm ergometer (a machine you pedal with your hands). The staff will show you how to use the machine.
	Start exercising slowly. If you use a treadmill, the speed and slope may be slowly increased. If you are using a bicycle, the seat and handlebars will be raised or made shorter for you. Do not grip the handlebars tightly. Just use them to balance yourself. Your doctor may slowly increase the force needed to push the pedals. The test will not hurt, but may tire you out.
	A doctor will watch you during this test. Alert him immediately if you start getting tired, have trouble breathing, or develop chest pain.
	When you reach your target heart rate, you will be asked to slow down. Do not stop until the doctor tells you.
	After the test, you can get off the exercise machine and sit down. Your vital signs and heart readings will be taken again during the next 10 to 15 minutes.

You feel light-headed or think you are going to faint.

	You have trouble breathing.
	You have signs of a heart attack: Chest pain that spreads to your arms, jaw, or back. Nausea. Trouble breathing. Sweating.