CAC Score vs ECG vs Stress Test: What Question Does Each Answer?

CAC score: plaque snapshot

A coronary artery calcium scan is a non-contrast CT that spots calcium in the coronary arteries. It is sometimes used to reclassify risk for people with borderline cardiovascular risk who do not have symptoms.

It is not a test for everyone, and it does not show soft plaque or whether an artery is currently blocked. The result is usually expressed as a score that helps guide prevention intensity and whether a statin or aspirin makes sense for you.

ECG: rhythm check, not a screen

An electrocardiogram records the electrical activity of the heart. The USPSTF recommends against routine ECG screening in asymptomatic low-risk adults and says evidence is insufficient for intermediate- or high-risk adults.

An ECG is useful when evaluating symptoms such as palpitations, chest discomfort, fainting, or an irregular heartbeat. It is not a general heart-health screening tool for healthy, symptom-free men and should not be ordered just for peace of mind.

Stress test: symptom or risk-driven

Stress testing is generally used when symptoms, abnormal findings, or high-risk conditions raise concern for coronary artery disease. It assesses blood flow to the heart under exertion or medication stress.

It is not a routine preventive scan for a healthy man with no symptoms. Using it for reassurance in low-risk people can produce false positives, unnecessary anxiety, and additional procedures that carry their own risks.

What this does not mean

A zero CAC score does not mean arteries are perfectly clean forever, and a high score does not mean you will have a heart attack. An ECG does not rule out all heart disease. These tests answer narrow questions and should not be stacked together for reassurance. Sources checked July 20, 2026. Independent clinician review is pending.

How to choose

Bring your risk factors and goals to a clinician. Ask whether any of these tests is indicated for you, whether the result would change management, and what it costs out of pocket. Some scans are self-pay, while others may be covered only under specific criteria.

Also ask what the follow-up plan would be for each possible result. A test is only worth doing if the answer changes what you and your clinician do next.