What is the single most important non-invasive test for assessing coronary artery disease?

Stress testing is considered the single most important non-invasive test for assessing coronary artery disease (CAD) because it evaluates the heart’s performance under physical stress, which can highlight potential ischemic changes indicative of CAD. This test can simulate the conditions that may lead to angina or other symptoms in patients who have blockages or narrowed coronary arteries.

The primary goal of stress testing is to determine how well the heart functions when it is challenged, making it pivotal for diagnosing CAD. It can involve exercise on a treadmill or the use of pharmacologic agents to increase heart rate and myocardial oxygen demand, thus revealing the presence of ischemia that might not be evident when the patient is at rest.

In contrast, cardiac catheterization is an invasive procedure that provides definitive anatomical details about coronary arteries but is not considered non-invasive. CT angiography, while useful for visualizing coronary artery anatomy and assessing CAD, is typically used in cases where coronary artery disease is suspected but is often not the first-line test due to cost, availability, and radiation exposure. Holter monitoring is primarily utilized for rhythm assessment and to evaluate for arrhythmias over a prolonged period but does not directly assess coronary artery disease itself.