Role of T1-weighted MRI in Identifying Coronary Intraplaque Hemorrhage: CATCH the Truly High-Risk Plaque.

Intraplaque hemorrhage (IPH) is a key feature of plaque vulnerability that contributes to atherothrombotic events. Non-invasive coronary plaque imaging has been challenging because of the small size of the coronary arteries and motion caused by cardiac contraction and respiration. Recent advances in magnetic resonance imaging (MRI) have enabled the non-invasive detection of coronary IPH. Compared with coronary computed tomography angiography and intravascular imaging modalities, MRI offers unique noninvasive tissue characterization based on intrinsic signal properties. Histopathological and intravascular imaging investigations have indicated that erythrocyte-derived materials, rather than lipid components, constitute the predominant substrate of coronary high-intensity plaques, reflecting recent IPH. This review summarizes the pathophysiological basis, imaging characteristics, and clinical implications of MRI-detected coronary IPH, in the context of other imaging modalities.