Mortality Risk in Symptomatic Patients With Nonobstructive Coronary Artery Disease

Abstract

Objectives Background Methods The prognostic significance of nonobstructive coronary artery plaques by CCTA is poorly understood. We prospectively evaluated consecutive adults from 2 centers undergoing 64-detector row CCTA without prior documented coronary artery disease (CAD) and without obstructive (50%) CAD by CCTA. Luminal diameter ste- nosis severity was classified for each segment as none (0%) or mild (1% to 49%), and plaque composition was classified as noncalcified, calcified, or mixed. Results During 3.1  0.5 years, 54 intermediate-term (90 days) deaths occurred among 2,583 patients (2.09%), with 4 early (90 days) deaths. Adjusted for CAD risk factors, the presence of any nonobstructive plaque was associ- ated with higher mortality (hazard ratio [HR]: 1.98, 95% confidence Interval [CI]: 1.06 to 3.69, p  0.03), with the highest risk among those exhibiting nonobstructive CAD in 3 epicardial vessels (HR: 4.75, 95% CI: 2.10 to 10.75, p  0.0002) or 5 segments (HR: 5.12, 95% CI: 2.16 to 12.10, p  0.0002). Higher mortality for nonob- structive CAD was observed even among patients with low 10-year Framingham risk (3.4%, p  0.0001) as well as those with no traditional, medically treatable CAD risk factors, including diabetes mellitus, hypertension, and dyslipidemia (6.7%, p  0.0001). No independent relationship between plaque composition and incident mortal- ity was observed. Importantly, patients without evident plaque experienced a low rate of incident death during follow-up (0.34%/year). Conclusions The presence and extent of nonobstructive plaques augment prediction of incident mortality beyond conven- tional clinical risk assessment. (J