The SHAPE guideline: ahead of its time or just in time?

In 2006, a grass roots movement called SHAPE (Screening for Heart Attack Prevention and Education) published a novel practice guideline for cardiovascular screening in the asymptomatic at-risk population. It suggested the use of noninvasive tests for subclinical atherosclerosis in cardiovascular risk assessment to target intensified preventive care to those at highest risk. The SHAPE guideline received much attention but not as much support from the "official" medical societies. However, subsequent studies published since 2006 have now provided strong supportive evidence for the strategy spearheaded by the SHAPE guideline. Indeed, the latest guidelines issued jointly by the American Heart Association and the American College of Cardiology have elevated recommendation levels for noninvasive imaging of subclinical atherosclerosis. This change is widely viewed as a significant step toward the SHAPE guidelines. The background for SHAPE and the evidence behind the recommendation to use coronary artery calcium score measured by computed tomography, carotid intima-media thickness and plaque measured by ultrasound, and ankle-brachial index in cardiovascular risk assessment is reviewed in this article.