Heart disease is the leading cause of death in the United States, with coronary artery disease being the common most type, according to the Centers for Disease Control and Prevention. A stress test can show whether a patient does or does not have heart disease. A stress test also determines the amount of stress a heart can handle before developing a reduced amount of blood flow to the heart muscle. The types of tests most commonly performed include exercise stress tests, adenosine stress tests, nuclear stress tests and stress echocardiograms.
Exercise Stress Test
The Harvard Medical School states that an exercise stress test makes patients work at a high level of exercise, causing their heart to work harder to see if it is receiving an adequate amount of blood flow and oxygen. According to the Harvard Medical School, the most commonly referred patients to exercise stress testing include those who appear to have known coronary artery disease and who have symptoms such as chest pain, shortness of breath, light-headedness, etc.
An exercise stress test can assist in diagnosing heart disease or assessing the effectiveness of heart disease treatment, such as prescribed medication. Doctors can also write an appropriate exercise prescription for patients from the results of their exercise stress test.
Adenosine Stress Test
Patients who cannot exercise must undergo a pharmacological stress test consisting of medication known as adenosine. The Cleveland Clinic states that adenosine works by dilating the blood vessels leading to the heart, which increases blood flow, thus stimulating exercise. Adenosine essentially mimics exercise immediately after it's taken. During "exercise," a small amount of a radioactive tracer is injected into the patient's vein. A special camera then detects the radiation released by the tracer to produce images of the heart on a monitor, according to the Cleveland Clinic.
This test allows doctors to determine how adequately the heart distributes blood flow during stress versus at rest and in diagnosing coronary artery disease.
Nuclear Stress Test
A nuclear stress test measures blood flow to the heart muscle, according to the Mayo Clinic. The Mayo Clinic states that a nuclear stress test involves injecting a patient with a medication that increases the blood flow to his heart muscle, essentially stimulating exercise. A special camera produces clear pictures of the heart tissue on a monitor. These images show areas of low blood flow and areas of damaged heart muscle. The images of the heart are taken during the stress phase and during the rest phase.
A nuclear stress test shows how well the heart works during stress (exercise) and at rest. Nuclear stress tests help doctors to diagnose coronary artery disease and heart enlargement, so doctors can devise a proper treatment plan.
Stress Echocardiogram
Medline Plus states that a stress echocardiogram determines how well the heart muscle responds to stress. A stress echocardiogram uses ultrasound imaging to show whether the heart is receiving enough blood flow and oxygen while under stress. Doctors can discover and potentially treat any blockage or disease from the results of a stress echocardiogram.
Medline Plus states that doctors typically refer patients who have symptoms of recent chest pain, recently had a heart attack, those at high risk for heart disease and those who have valve problems to have a stress echocardiogram.
