CMR-LGE imaging features of dilated cardiomyopathy and relationship with left ventricular function

Previous studies have reported positive late gadolinium enhancement (LGE) rates ranging from 30% to 72% in dilated cardiomyopathy (DCM). There is no unified consensus on the relationship between different LGE features and left ventricular (LV) function. This study aimed to demonstrate the LGE characteristics in patients with DCM and to further investigate the relationship between LGE distribution, location and load and LV function. A total of 193 patients diagnosed with DCM were enrolled from February 2018 to May 2020 in the First Affiliated Hospital of Nanjing Medical University. All patients underwent cardiac magnetic resonance (CMR). The parameters of LV function, volume, and global LGE burden were obtained. According to the myocardial level of LGE distribution, stage of LGE distribution, and LGE load, the grouping included 3 types. A total of 127 patients (80.9%) were enrolled with LGE positive. The median LV LGE load was 15.5%. The proportion of midmyocardial and subepicardial myocardial involvement was significantly higher than that of subendocardial myocardial involvement (60.6%, 50.4% vs. 10.2%, P < 0.001). LGE distributed more often in the ventricular septum, which was significantly higher than in the free-wall segments. Left ventricular ejection fraction and global radial strain in the midmyocardial LGE group and the multilayer LGE group were lower than in the LGE(-) group (p < 0.005). Kaplan-Meier survival analysis revealed that compared to the LGE-negative group, both the midmyocardial LGE group and the multilayer LGE group exhibited significantly elevated risks of long-term MACE (Log-rank p < 0.05). Dilated cardiomyopathy LGE most commonly involves the septal myocardium of the basal and intermediate segments of the left ventricle, and predominantly involves the middle layer and subepicardium. LGE involvement of the LV midmyocardium is associated with poorer LV function and higher risks of long-term MACE.