Stress tests are used to diagnose problems with the heart, including coronary artery disease, heart valve disease or heart failure, reports the National Heart Lung and Blood Institute. Stress on the heart can produce symptoms that are not evident when the heart is at rest, so the patient exercises on a treadmill or stationary cycle until he reaches his target heart rate or until he begins to have chest pain, shortness of breath or other adverse symptoms. If the patient cannot exercise, the technician administers medication intravenously that quickens the heart rate. Radioisotopes are administered if the physician has ordered a nuclear stress test that provides images of the heart at rest and under stress. Dangers vary according to the type of test administered.
Heart Problems
The risk of having a heart attack or dying during a stress test is about 1 in 5,000, according to the National Heart Blood and Lung Institute. Sometimes patients experience an abnormal heart rate or arrhythmia that is resolved as soon as your heart is at rest. If it does not resolve, the patient may need to be admitted for treatment.
Hypotension
Some patients become dizzy or feel faint because their blood pressure drops during the test, reports the National Heart Lung and Blood Institute. When the heart returns to its resting rate, this problem usually resolves.
Medication Side Effects and Reactions
Patients who cannot exercise to reach a maximal heart rate will receive medications that stress the heart. Some patients feel jittery or uncomfortable after receiving the medication, notes the National Heart Lung and Blood Institute. Others may have asthma-like reactions such as shortness of breath or wheezing which can be serious. The symptoms may last for several hours. Some patients complain of chest pain or of feeling flushed when these medications are administered, reports the Mayo Clinic. Others have nausea, vomiting or a feeling that the heart is racing, according to the National Institutes of Health. Patients undergoing a nuclear stress test may have an allergic reaction to the radioactive dye that is used for contrast.
