If you’re experiencing chest pain or tightness, or shortness of breath, it’s important to talk to your doctor. These symptoms could mean you need a heart evaluation. A test like this is called a heart stress test.
A heart stress test is one of the most common ways to evaluate your cardiovascular system and can detect heart disease. Three basic types of stress tests are used.
- Treadmill exercise test: Measures your heart performance while exercising on a treadmill. If a patient cannot exercise, alternative methods including medications are used to reach the same effect.
- Stress echocardiography: Ultrasound imaging that shows how well your heart is working to pump blood through your body when “stressed” by various modalities.
- Cardiac nuclear stress test: A nuclear tracer element is delivered by IV to evaluate blood flow into the heart at rest and when subjected to “stress” by exercise or medications.
Stress test limitations
While stress tests can detect heart disease and predict the likelihood of cardiovascular problems, such as heart attacks, they do have limitations.
“A stress test cannot detect blockages that do not impact blood flow to the heart muscle,” said Dr. Dan Gavrila, an interventional cardiologist at Marshfield Clinic Health System. “It’s believed the blockage has to be at least 50 percent to have an impact on the blood flow, but any percentage of plaque buildup in the arteries can rupture, leading to a heart attack.”
Stress tests go back decades and are very helpful in determining if a patient’s symptoms are related to significant blockages. Their results, while generally reliable and very useful in both the diagnosis and the prognosis of heart disease, can sometimes be misleading.
“Like any other medical test, the results of a stress test need to be placed in the clinical context of a particular patient, which needs to be explained by a doctor,” Dr. Gavrila said. “Stress tests can be unreliable in predicting disease, especially in certain areas of the heart muscle.”
Despite its limitations, if stress test results are normal, especially after exercise, the likelihood of that patient developing significant cardiovascular problems in the next few years is low.
Next step: Angiography
If a stress test indicates an abnormality and the risk of heart disease is thought to be high, an angiography is recommended and usually performed.
A long, thin tube called a catheter is threaded through blood vessels to the heart, commonly inserted through the wrist blood vessels, or if that is not possible groin blood vessels may be used. Using a special dye, doctors can see the location and severity of the blockages very precisely. Depending on the severity of the blockages, they can potentially be treated at the same time. This is usually done for people who are in the midst of having a heart attack or who have severe symptoms that have not been alleviated by medications alone.
Another less invasive alternative to quantify the severity of blockage disease is what’s called a coronary CT angiography. Doctors can take images of blood vessels using X-ray techniques instead of placing a catheter in the heart. While this can be a good option for some patients, especially those who are low-risk, the presence of significant blockages will need to be confirmed by an invasive catheter angiography.
“The most important thing you can do to avoid heart issues is prevent blocked arteries in the first place,” Dr. Gavrila said. “A healthy lifestyle is critical and the most straightforward way to avoid heart disease to start with. That includes a healthy diet and regular exercise.”
It’s also important to establish a primary care doctor and regularly check your blood pressure, cholesterol levels, risk of diabetes, and make every effort to quit smoking if you have a tobacco addiction.
“If these main risk factors are properly addressed, you may never need a stress test,” Dr. Gavrila said. “But if that does not work and you think you need medical attention, please do not hesitate to contact us immediately. We are here for you.”