Abstract 306: Mortality Incidence of Patients With Non-obstructive Coronary Artery Disease Assessed by CT Angiography
Background: We previously reported that event free survival rates of symptomatic patients with CAD diagnosed by computed tomography angiography (CTA), decreased proportionally from normal coronaries (98.3%) to non-obstructive CAD (95.2%) to obstructive CAD (87.5%).
Objectives: We analyzed the clinical outcomes of symptomatic patients with non-obstructive (luminal stenosis<50%) CAD as determined by CTA in an outpatient setting.
Methods: One thousand and one hundred and two symptomatic patients (age 59±14 years, 69.9% male) with non-obstructive CAD were prospectively followed for a mean 78±12 months. Multivariable Cox proportional hazards models were developed to predict allcause mortality.
Results: The death rate of patients with non-obstructive CAD was 3.1% (34 deaths). The date rate increased proportionally from calcified plaque (1.4%, 7/501) to mixed plaque (3.3%, 16/486) to non-calcified plaque (9.1%, 11/104). Non-calcified and mixed plaques in patients with non-obstructive CAD were found to be an independent predictor of all cause mortality. Risk-adjusted hazard ratio of all cause mortality for CTA diagnosed non-obstructive CAD was 2.6 for non-calcified plaques and 7.5 for mixed plaque as compared to calcified plaques. Risk facot adjusted event free survival rate decreased substantially from 98.6% in calcified, to 96.7% in mixed plaques to 90.9% in non-calcified plaques in the patients with non-obstructive CAD (p<0.001).
Conclusions: Current study reveals that non-calcified and mixed coronary plaques detected by CTA provides incremental value in predicting all cause mortality in symptomatic patients independent of conventional risk factors.