Does a myocardial perfusion scan show blockage in the heart?

Blood Perfusion. The angiogram shows anatomic blockage of coronary arteries. The myocardial perfusion scan shows blood flow to the heart. Blood flow can get past large blockages (shown on angiography) if there are enough small, collateral vessels present.
Yes. The myocardial perfusion scan is designed to show if there is a blockage in the coronary arteries. The tracer (thallium lets say) follows the blood in the heart and seen on a camera.If a blockage is present it will show up as a dark spot where the tracer couldnt get to.The next step is a heartcath usually, these scans arent a 100% and you can have false positives and negetives.