When we think about a cardiac arrest, we usually imagine dramatic scenes – chest pain, ambulances, and emergency surgeries. However, the truth is, for most people, heart disease is quietly brewing long before any symptoms actually show up. That’s exactly where a test called the Coronary Artery Calcium (CAC) scan comes in. It’s quick, non-invasive, and surprisingly underused, especially considering how much life-saving information it can provide.
“Yes, traditional blood tests and stress tests are useful, but they don’t actually show the disease. CAC scanning does,” says Dr. Dinesh Narang, a senior interventional cardiologist at the Lilavati Hospital. “It’s one of the few tools we have that can spot a heart attack risk that’s otherwise invisible.”
It is a CT scan with a very specific goal: checking for calcium deposits in the arteries that feed our heart. These deposits are early warning signs of plaque build-up (known as atherosclerosis) which can eventually lead to cardiac arrest. The test gives you a “calcium score” which speaks volumes about your heart health and whether you need to heed warning signs.
A score of 0 translates to Zero Plaque, which means you’re in the clear. No visible heart disease. Similarly, a calcium score between 1–100 is Mild Plaque, which shows some build-up, but it is usually manageable with lifestyle changes. A score on the scan that reads between 101–400 is Moderate Plaque. That means it is time to get proactive. Medications like statins may be recommended for such patients.
A score of 401+ is known as Extensive Plaque. This simply means you’re at high risk; immediate action is non-negotiable for these patients.
Dr. Aakruti Mehta, a preventive cardiologist and faculty member, believes, “a CAC score of zero is the most powerful negative predictor we have in cardiology. It’s like getting a clean bill of health for your arteries.” And 401 plus is also an assurance that your heart is at risk.
There’s a caveat here that experts want you to be mindful of. The CAC isn’t a scan for everyone. It is for those patients who fall somewhere “in-between” — when you’re not low-risk, but not high-risk either.