Coronary angiography overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Cardiac catheterization refers to the insertion of hollow tubes (catheters) into structures of the heart. When catheters are inserted into the coronary arteries that supply blood to the heart muscle (the myocardium), this instrumentation is called cardiac catheterization. Cardiac or coronary catheterization is to be distinguished form left heart catheterization in which catheters (hollow tubes) are inserted into the blood filled chambers of the heart.

Once the catheter is inserted into the coronary artery, coronary angiography is the process of injecting iodinated contrast material (i.e. dye) into the coronary arteries to assess the coronary circulation. Coronary angiography is performed for both diagnostic and interventional (treatment) purposes. Coronary angiography is a visually interpreted test performed to recognize occlusion, stenosis, restenosis, thrombosis or aneurysmal enlargement the coronary artery lumens, heart chamber size, heart muscle contraction performance and some aspects of heart valve function. The relevant problems that the test deals with most commonly occur as a result of advanced atherosclerosis, atheromaactivity within the wall of the coronary arteries. Less frequently, other issues, valvular, heart muscle or arrhythmia issues are the primary focus of the test.

Coronary artery luminal narrowing reduces the flow reserve for oxygenated blood to the heart, typically producing intermittent angina if very advanced; luminal occlusion usually produces a heart attack. However, it has been increasingly recognized, since the late 1980s, that coronary catheterization does not allow the recognition of the presence or absence of coronary atherosclerosis itself, only significant luminal changes which have occurred as a result of end stage complications of the atherosclerotic process. See IVUS and atheroma for a better understanding of this issue.