Can you describe a dobutamine stress test?

IV Chemical Stress: An intravenous is started . A radioactive substance is given and a picture of the heart muscle at rest is taken. Then Dobutamine is dripped in to increase the heart rate ( instead of walking on a treadmill) . Then another picture is taken of the heart muscle. The pictures are compared. The pictures look like donuts. If there is a bite out of the donut , that means less or no blood is going there.

Chemical "Stress": Stimulant dobutamine, injected by IV drip to ↑ heart muscle intensity & rate of contraction, in place of walking. The ↑ed intensity & BP is the stress. Radioactive isotope is injected iv, heart muscle cells pump the isotope inside semi-proportional to cell health & blood flow. A radiation camera detects some of the radiation exiting the body. Only severe, not mild, artery disease can be detected.

Drug induced stress: If exercise on a treadmill is not an option (too much stress on the heart) due to a person’s medical condition, may use an intravenous medication called dobutamine. Dobutamine causes heart to beat faster and will mimic the effects of exercise on the heart. Stress tests usually can be nuclear with radiotracer or with echocardiography.