Stress Test: Types and Indications

The stress test is used to assess the functioning of the heart during stress either with exercise or medicine. This test checks for the blockage in the heart arteries by evaluating EKG during stress and pictures of the heart if taken.

Types of Stress test

• Treadmill stress test
• Stress Echocardiogram
• Nuclear stress test

Preparation for the test

• Not to eat or drink for alteast 4-6 hours before the procedure
• Hold certain Blood pressure medications which slow down the heart rate
• Not to have caffeine for atleast 24 hours in case of a nuclear stress test.
• You can drive home yourself after the stress test.

How much time dose it take for stress test?

• Treadmill stress test: 1 hour
• Stress echocardiogram: 1 hour
• Nuclear Stress test: 3-4 hours

Procedure

• For this procedure, your doctor will first talk to you about normal exercise habits to determine the difficulty of the test. After that, a technician will put sticky patches with an electrode on your chest to record the electrical activity of your heart. A cuff will be attached to your arm to measure blood pressure. You will then be asked to walk on a treadmill. The exercise test will slowly increase in difficulty until your heart rate reaches the target or you develop symptoms because of which you cannot continue like Chest pain, shortness of breath, Arrhythmia, Fainting or Abnormal patterns on ECG. If you choose to not exercise or your heart rate does not reach a certain level then you will be given a drug( dobutamine or lexiscan)  that mimics exercising; you may feel an increase in heart rate and flushing after the drug is given.

After the test, you will be asked to lie down while the heart functions are being monitored. If a chemical or medicine stress test is done then additional pictures of the heart will be taken with an echocardiogram or nuclear camera.

Indications for Stress test

Your doctor will suggest you get a stress test done:

• If your doctor suspects that you have had an episode of heart attack: to assess the function of the heart and decide on the future course of treatment.
• To diagnose coronary artery disease: this disease is caused due to deposition of cholesterol and calcium in the wall of the arteries that supply blood to the heart.
• To diagnose arrhythmia

Risks with Stress test

Stress test increases the workload of the heart and may sometimes lead to complications like:

• Heart attack: occurs in about 1 in every 2500 cases
• Arrhythmia can be precipitated due to the stress testing

Results

Your doctor will use the results of the stress test to determine the health of your heart and decide upon the future course of treatment. If the stress test is abnormal you may be referred for further evaluation with Cardiac catheterization or CT angiogram. If the results of the plain treadmill stress test are not conclusive you may be advised to undergo a repeat stress test with an echocardiography stress test or a nuclear stress test.

Resource:

•  AHA/ACC guidelines for exercise testing.