The technology of radiological examination of the heart and blood vessels, It requires sophisticated equipment and technique because of the speed with which the injected radiopaque material passes through the heart Called also angiocardiography. X-ray examination of the heart and its blood vessels following intravenous injection of radiopaque fluid. Coronary angiograms are part of a general group of procedures known as heart (cardiac) catheterization. Heart catheterization procedures can both diagnose and treat heart and blood vessel conditions. A coronary angiogram, which can help diagnose heart conditions, is the most common type of heart catheterization procedure.