Letters Section Editor: Stephen J. Lurie,
MD, PhD, Senior Editor.
To the Editor: Dr Greenland and colleagues1 stated that "absence of CACS did not preclude the
risk of a CHD [coronary heart disease] event as has been reported in some
other studies." However, in explaining why individuals without detectable
CAC might experience coronary events, the authors did not consider that their
scanning methodology used a 6-mm scan thickness, twice the scan thickness
used in other prognostic studies. For instance, Callister et al2 evaluated
patients with both 3-mm and 6-mm scans and concluded that "[a] 6-mm slicing
protocol is significantly less sensitive than a 3-mm protocol for the detection
and quantification of CAC. Since one-third of coronary events occur in patients
with low CACS, a 6-mm protocol might be unreliable for risk assessment because
of substantial loss of information."
Budoff MJ, Ehrlich J, Hecht HS, Rumberger JA. Use of Coronary Calcification Scores to Predict Coronary Heart Disease. JAMA. 2004;291(15):1831. doi:10.1001/jama.291.15.1832-a