You’re at the doctor for a checkup. You go through the typical battery of tests and presume everything is OK. But at the end of your visit, your doctor says, “I’d like you get a chemical stress test.” Now your mind is swimming with questions.
During a chemical stress test, your physician will administer a drug to “stress” your heart (make it beat faster). The doctor also will take images of your heart. The images will show you and your doctor how your heart is functioning, but there’s more to it than that.
To calm your fears, we asked North Ohio Heart/Ohio Medical Group Cardiologist Dr. Theodore Pacheco to answer some common questions about chemical stress tests.
When is a Chemical Stress Test Performed?
If you’re showing signs of heart disease, current guidelines from the American Heart Association and the American College of Cardiology recommend getting a stress test done. The test can confirm the diagnosis, determine if there is decreased blood flow to a part of your heart and tell you how bad it is. A stress test also can tell you you’re in tip-top shape, so it’s not always bad news.
Stress tests typically are done on a treadmill. You walk or jog on it to get your heart rate up, but not everyone can do this. If something will keep you from getting on the treadmill—like back trouble, joint pain or unsteady gait—doctors will order a chemical stress test.
Dr. Pacheco says a chemical stress test also may be done if your resting electrocardiogram, or EKG, shows some abnormalities.
What Type of Drugs are Used During a Chemical Stress Test?
The types of medications that may be used during your stress test could include:
Dobutamine—causes the heart rate to rise and the blood pressure to increase.
Adenosine—causes dilation of all the blood vessels in the body.
Lexiscan (regadenoson)—Dr. Pacheco says this is now the most commonly used medication because it is tolerated well. It also causes enlargement of the blood vessels in the body and increased blood flow to the heart.
How is a Chemical Stress Test Performed?
You’ll lie on your back and your doctor will administer the drug. An EKG will be used to monitor your heart’s activity.
Dr. Pacheco says the medication is administered rapidly and the body breaks it down quickly. Most patients experience few, if any, side effects.
The EKG will be used to monitor how your heart is handling the drug. Your doctor will look at three things:
- 1. Resting pictures of the heart, using an echocardiogram (an ultrasound of your heart), or gamma camera.
- 2. Effects of the stress medication
- 3. Stress pictures of the heart
Should I Take My Medications on the Day of the Test?
Your doctor will tell you which medications should be stopped (if any) before you take the stress test. You also should bring a list of your medications, including over-the-counter medications, to your test.
How Long Does a Chemical Stress Test Take?
You can expect a chemical stress test to take anywhere from two to four hours.
How Reliable is a Chemical Stress Test?
Chemical stress tests are very accurate and good at predicting the likelihood of some type of adverse heart event happening over the next few years, Dr. Pacheco says. The results may range from completely normal (indicating you have a low risk of heart events) to highly abnormal (indicating a high risk for future heart problems).
How Soon Do You See Results?
You’ll get a preliminary report from the physician who performs your test, but full results will take a few days to complete.
How Safe is a Chemical Stress Test?
The risk you’ll experience from a chemical stress test is very small. It’s about the same as if you were taking a jog around your neighborhood, or a run up a flight of stairs.
You’ll also be surrounded by a team of doctors and nurses who will know how to handle rare complications like:
- Irregular heartbeat, caused by the stress on your heart
- Chest pains; tell your doctor right away
- Allergic reaction to the medication
In some cases, the medication could make you feel nauseous, or give you a headache. Dr. Pacheco says medication, or even caffeine, can be given to help with these occasional side effects.
Although hearing that you need a chemical stress test sounds scary, it can be helpful in determining the health of your heart. This is especially true if you’re showing signs of heart disease. If you’d like to make sure you’re heart health is on the right track, or to find out which heart disease risk factors matter most, click the link to download our free guide, “Heart Disease Facts.”