Author Affiliations: Noninvasive Cardiovascular Imaging Program, Brigham and Women's Hospital, Boston, Massachusetts (Dr Blankstein); and Cardiac MR PET CT Program, Massachusetts General Hospital, Boston, Massachusetts (Dr Hoffmann) (firstname.lastname@example.org).
To the Editor: The study by Dr Shreibati and colleagues1 concluded that CCTA led to increased downstream testing, interventions, and costs compared with functional assessment for coronary artery disease (CAD). We would like to point out 2 important limitations with respect to the study population and the timing of the analysis.
The strength of CCTA lies in its high negative predictive value and the ability to rule out the presence of significant stenosis among patients with low to intermediate risk of obstructive CAD. Older age is the single most important factor associated with the prevalence of CAD. Because older patients are more likely to have coronary artery calcifications, which are associated with nondiagnostic or false-positive examinations,2 older patients may have increased subsequent testing and interventions. Thus, it has been suggested that the most efficient use of CCTA (defined as a significant change in posttest probability for both a negative and a positive examination) is in men younger than 55 years and women older than 65 years.3 However, the mean age of 74 years in the population examined is 15 years higher than that of patients studied in multicenter CCTA accuracy trials4 and more than 21 years older than patients included in acute chest pain studies.5
Blankstein R, Hoffmann U. Evaluation for Coronary Artery Disease and Medicare Spending. JAMA. 2012;307(9):911-912. doi:10.1001/jama.307.9.911-b