Abstract 10821: The Presence of Non-obstructive Coronary Artery Disease on Coronary Computed Tomography Angiography Re-classifies Guideline-based Statin Eligibility
Background: AHA/ACC guidelines advise using 7.5% threshold of 10-year risk for atherosclerotic cardiovascular disease (ASCVD) events to determine eligibility for statin therapy. Coronary Computed Tomography Angiography (CTA) provides prognostic information for ASCVD events as well. We tested the hypothesis whether presence of non-obstructive CAD (<50% stenosis) as detected by CTA could be used to improve risk assessment per AHA/ACC guidelines in stable patients.
Methods: We performed a systematic literature review to identify studies that assessed the prognostic value of coronary CTA findings for ASCVD events. The characteristics of study subjects at baseline, follow-up information, and outcomes were collected. We selected studies that provided hazard ratio (HR) for ASCVD events in patients with non-obstructive CAD and performed a meta-analysis. We incorporated the pooled HR into the standard 10-year ASCVD pooled cohort equation and derived equivalents for the 7.5% 10 year event risk for those with and without non-obstructive CAD and performed a sensitivity analysis using the lower and upper bounds of the confidence intervals of the pooled HR from the meta-analysis.
Results: We identified 20 studies (22,036 subjects, 53% male, median follow-up 31 months) that assessed the prognostic value of CAD as detected by CTA. The studies that provided HR for ASCVD events were used for the meta-analysis. The pooled HR for incident ASCVD was 3.2 (95% CI 1.5-6.7). Equivalents for the 7.5% 10 year event risk for those with non-obstructive CAD were as low as 2.0% (African American women) and for those with no CAD as high as 33.8% (African American men). (Table 1)
Conclusions: Non-obstructive CAD is an independent predictor of ASCVD events. Incorporating information on the presence of non-obstructive CAD into the AHA/ACC ASCVD risk calculator provides gender and ethnicity specific equivalents for the 7.5% threshold, which may improve efficiency and accuracy of statin therapy.
Author Disclosures: H. Emami: None. R. Takx: None. T. Mayrhofer: None. S. Janjua: None. J. Park: None. A. Pursnani: None. M.T. Lu: None. M. Ferencik: None. U. Hoffmann: None.
- © 2015 by American Heart Association, Inc.