Abstract 11798: Hyperintense Plaque Detected by Magnetic Resonance T1-weighted Imaging Relates to Intracoronary Thrombus Visualized by Optical Coherence Tomography in Patients With Angina Pectoris

Abstract

Aims: Screening of the patients with vulnerable plaque is important for prevention of the onset of acute cardiovascular events. Several studies have shown that hyperintense plaques (HIPs) of the carotid artery on magnetic resonance noncontrast T1-weighted imaging (T1WI) indicate the presence of intraplaque hemorrhage containing methemoglobin. Coronary plaque imaging with T1WI is challenging, and the clinical significance of coronary HIP on T1WI remains unknown. The aim of this study was to compare HIPs on T1WI with coronary plaque morphology assessed by optical coherence tomography (OCT) in patients with angina pectoris. Methods and results: Thirty-five lesions from 35 patients with either stable or unstable angina pectoris were examined in this study. All patients underwent T1WI within 24 hours before the day on which invasive coronary angiography was performed, and preinterventional OCT was performed on the culprit lesion. Following OCT, the filter-based distal protection device (Filtrap, Nipro, Japan) was deployed to reduce the risk of distal embolization in all patients, and stenting was performed according to routine practice. Of the 35 lesions studied, 21 (60%) were HIPs and 14 (40%) were non-HIPs. The signal intensity of coronary plaque to cardiac muscle ratio in HIPs was significantly higher than that in non-HIPs. There were no significant differences in the frequency of thin-cap fibroatheroma and plaque rupture between HIPs and non-HIPs. In contrast, the frequency of thrombus (P<0.001) and lipid-rich plaque (P<0.05) was significantly higher in HIPs than in non-HIPs. Multivariate analysis revealed that intracoronary thrombus was an independent factors associated with HIPs. Moreover, the frequency of filter slow/no-reflow in HIPs was significantly higher than in non-HIPs. HIPs as an indicator of filter slow/no-reflow had sensitivity of 100%, specificity of 56%, positive predictive value of 67%, and negative predictive value of 100%.

Conclusions: This study shows that the HIPs on T1WI in angina patients relate to the presence of intracoronary thrombus as detected by OCT imaging, and filter no-reflow phenomenon.