A long flexible catheter is inserted through the blood stream to deliver dye (contrast agent) into the arteries making them visible on the x-ray. This test can help diagnose a stroke, aneurysm, arteriovenous malformation, tumor, clots, and arterial stenosis.

What does an angiogram prove?

Why it's done. A coronary CT angiogram is mainly used to check for narrowed or blocked arteries in your heart (coronary artery disease). However, your doctor can use it to check your heart for various conditions.

Why would a doctor order an angiogram?

An angiogram can show if your coronary arteries are narrowed, where they are narrowed, and by how much. It can help your doctor see if a change in treatment—such as medicines, angioplasty coronary artery bypass surgery—can improve your angina or lower your risk of heart attack or death from heart problems.