Dobutamine stress echocardiography is a variation of exercise echocardiography to unmask coronary artery blockages. During this test, the heart is stressed by infusing dobutamine. Dobutamine is commonly used to treat patients with low blood pressure, to improve circulation and as a diagnostic testing agent. Dobutamine increases the heart rate and blood pressure and the degree to which the heart contracts. It therefore mimics the effects of exercise for patients who are unable to exercise to a sufficient degree.
The examination starts with the resting transthoracic echocardiogram. After that, dobutamine is infused at a low dose. Following, the dose is increased every three minutes to increase the heart rate and cardiac contractions. At each of these three-minute stages, the heart is scanned using transthoracic echocardiography. An electrocardiogram has to be continuously recorded and blood pressure automatically checked every three minutes.
Disconcerting and stress-related sensations of the patient is to expect during infusion of dobutamine and does not represent any harmful effect. As soon as the infusion is completed, it is discontinued and usually within five to ten minutes the heart rate and blood pressure will return to the levels before starting the exam. Only qualified staff with specific training should perform this test. As for all types of cardiovascular stress testing, all of the necessary equipment and medicines to treat complications must be available in the stress testing room.

Stress echocardiograms are used for detection of coronary artery disease, or to determine the cardiac performance. Stress echocardiograms are less performed to evaluate pulmonary artery pressures, pulmonary hypertension or the significance of valvular heart disease.
Stress increases the degree to which the heart contracts. After a myocardial infarction there will be a region of the heart muscle that contracts abnormal at rest. This area may worsen with stress. A coronary artery blockage most often do not impairs the function of the heart at rest. With stress, a region of the heart does not receive enough blood to work effectively and wall motion abnormalities occur. The echocardiographer compares rest and exercise and can determine the presence and severity of a coronary artery blockage.

Stress echocardiograms involve:
A bicycle stress echocardiogram involves transthoracic echocardiography performed at the rest baseline and after or during different stages of physical exercise.
A dobutamine stress echocardiography uses the drug dobutamine instead physical exercise.
Transthoracic echocardiograms are routinely performed during stress and rest.
Cardiovascular stress represents a minimal risk to the patient.

See also Transesophageal Echocardiography, Echocardiography, M-Mode, Curved Transducer, Doppler Ultrasound, History of Ultrasound and History of Ultrasound Contrast Agents.