The US Preventive Services Task Force (USPSTF) has found insufficient evidence (benefits vs. harms) to support CAC testing over traditional risk assessments for cardiovascular disease in adults without heart symptoms.
We have been told for decades now that detecting cardiac disease early is better than waiting for symptoms to appear, which on the surface sounds reasonable. However, years of experience belies this supposed axiom, and in fact some screenings, in the guise of “early detection,” can be downright dangerous.
In the Emergency Department, that is, at least.
A few years ago, there were several major studies evaluating the safety of a CT coronary angiogram-based study for the evaluation of chest pain in the Emergency Department. The constant challenge, however, has been specificity – not only with respect to whether the CT can accurately detect stenoses, but the clinical relevance of the stenoses.
But a zero calcium score can be useful to avoid statins, some argue.
Despite the remarkable mass of robust data supporting the prime role of CAC in risk assessment of the intermediate-risk population as well as several large subgroups, with the concept of atherosclerosis itself being a more potent predictor of CAD than risk factors for atherosclerosis having been validated in every study, CAC has not been incorporated into the mainstream of clinical cardiology and has been downgraded in the 2013 guidelines.
In 2013, the American Heart Association declared the coronary artery scan beneficial, but it still hasn’t taken off as a proactive route for all Americans – and many docs still don’t think it’s an effective solution to the problem of heart disease in the masses.
Advocates for the scan say it should be used to “de-risk” people. It can let those who do not want to take statins know whether their chance of a heart attack is actually extremely low.
But measuring coronary calcium is not a surefire indication of a person’s risk. For one thing, the test measures arterial plaque that is hardened and firmly attached to the lining of coronary vessels. It does not measure the soft plaque that can rupture and travel through the coronary circulation until it reaches a narrowing it cannot pass, leading to a heart attack or stroke.
Unlike measurement of traditional risk factors like blood pressure and lipids, however, CAC measurement has significant downsides...
Everyone interviewed for this article agreed that CAC has no role as a widespread screening modality in individuals at low risk. The fact that numerous centers in the United States persist in offering cheap calcium scans without appropriate pre-screening has clearly damaged the test's reputation in the wider cardiology community.
A simple heart scan could save many of these lives, but THE WIDOWMAKER reveals that a hidden battle fought inside America’s medical establishment has pitted prevention against intervention keeping scans in the shadows while cardiac surgeries soar.