What is the most accurate method for confirming suspected coronary artery disease and assessing its severity?

• A. Computed tomography with coronary angiography
• B. Exercise electrocardiogram with 24-hour Holter monitor
• C. Magnetic resonance arteriography with contrast dye
• D. Cardiac catheterization with coronary angiography

Answer: (D)

Direct visualization of the coronary arteries with cardiac catheterization and coronary angiography is the most accurate way to confirm suspected coronary artery disease and to gauge how severe the blockages are. By threading a catheter to the heart and injecting contrast, you can see the exact lumen size and location of any narrowing, giving a precise percent stenosis. It also provides physiologic information—pressure measurements and, when used, techniques like fractional flow reserve—to determine whether a lesion actually reduces blood flow enough to cause ischemia. This combination of anatomical detail and functional significance is why invasive coronary angiography is considered the definitive test for confirming CAD and guiding treatment decisions.

Noninvasive tests like exercise ECG or Holter monitors can detect ischemia or rhythm issues but don’t confirm the anatomy or quantify stenosis. CT coronary angiography can image anatomy noninvasively but doesn't always match the accuracy of invasive angiography for determining functional significance or guiding intervention. MR-based vascular imaging is less routinely used for CAD assessment and lacks the same level of accuracy for coronary stenosis.