Many people without any known heart disease or heart symptoms may still have blocked arteries full of atheroslerotic plaque. Early detection of coronary artery disease (CAD) using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring could detect the presence and severity of CAD even in those with no known issues on clinical grounds. A large study in Sweded used CCTA to determine the prevalence, severity, and characteristics of CAD and its association with CAC scores in a general population.
The researchers recruited individuals age 50 to 64 years to have an assessment of silent CAD. The study includes individuals without known CAD (ie, no previous myocardial infarctions or cardiac procedures). CT mages were scored for CAC. CCTA images were visually read and scored for CAD per segment (defined as no atherosclerosis, 1% to 49% narrowing, or ≥50% narrowing).
In total, 25 182 individuals without known coronary heart disease were included (51% women). Any CCTA-detected CAD was found in 42%. Any significant narrowing (≥50%) was found in 5.2%; more serious locations of narrowing in the left main, proximal left anterior descending artery, or 3-vessel CAD was found in 2%; and any noncalcified plaques in 8.3% of the population.
Onset of CAD was delayed on average by 10 years in women. CAD was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 46% had significant narrowing. In those with 0 CAC, 6% had atherosclerosis but only 0.4% had significant narrowing.
Using CCTA in a large sample of the general population without established CAD, silent coronary atherosclerosis was common and found in 42% that did not know they had any CAD. High CAC scores over 400 convey a significant probability of substantial stenosis, and 0 CAC does not exclude CAD from non-calcified soft plaque. So if you feel fine, congratulations, but you may still have CAD. Test Not Guess by at least a CAC score and possible a CCTA.