A prospective natural-history study of coronary hyper-intense plaques detected by non-contrast T1-weighted magnetic resonance imaging

Abstract

Background: We previously showed that coronary hyperintense plaques (HIPs) detected with noncontrast T1-weighted imaging (T1WI) are strongly associated with positive coronary remodeling, remarkably lower Hounsfield units, and ultrasound attenuation. It remains unclear, however, whether the presence of coronary HIPs is associated with an increased risk of coronary events. Methods: We examined the signal intensity of coronary plaques using noncontrast T1WI in 568 high-risk patients 55 years of age or older who had evidence of coronary artery disease (CAD) or diabetes plus one other cardiovascular risk factor. A coronary HIP was defined as a signal that is ≥140% of the adjacent myocardium. All patients were divided into 4 groups according to the presence or absence of HIPs and CAD, i.e., HIP-positive + CAD (n=90), HIP-positive + no CAD (n=46), HIP-negative + CAD (n=111), and HIP-negative + no CAD (n=321). The median follow-up duration was 3.9 years. The primary end point was a composite of cardiac death, myocardial infarction, cardiac troponin T-positive unstable angina, and percutaneous coronary intervention due to progressive angina. Results: Compared to the non-HIP group, patients with HIPs were significantly more likely to experience a cardiovascular event (log-rank p<0.001, Figure). Multivariate Cox regression analysis identified the presence of HIPs as the strongest independent predictor of cardiovascular events (hazard ratio, 3.35; 95% confidence interval, 1.77–6.36; p < 0.001), compared to a history of CAD (hazard ratio, 2.03; 95% confidence interval, 1.15–3.59; p=0.01) and other coronary risk factors. ![Figure][1] Figure 1 Conclusions: Compared with patients without HIPs, patients with coronary HIPs are at a higher risk of cardiovascular events developing over time. [1]: pending:yes