A high-risk late gadolinium enhancement pattern is associated with arrhythmic events in patients with dilated cardiomyopathy

Abstract Introduction Myocardial fibrosis constitutes a substrate for the development of ventricular arrhythmias in patients with non-ischaemic dilated cardiomyopathy (DCM). Late gadolinium enhancement (LGE)-cardiac magnetic resonance (CMR) imaging represents a powerful tool for arrhythmic risk stratification. Moreover, arrhythmic risk is determined by the extent and localization of LGE. A high-risk LGE pattern, defined as the presence of epicardial, transmural or septal plus free-wall LGE, has been recently associated with a higher incidence of arrhythmic events comparing with other LGE patterns. Purpose To evaluate the prevalence of a high-risk LGE pattern in patients with DCM and its association with arrhythmic events. Methods From 2014 to 2021, all patients (N = 229) with DCM were prospectively evaluated in our tertiary care hospital. 174 patients underwent a 1.5 Tesla scanner CMR as part of the diagnostic workup and were included in the present study. The primary endpoint was a composite of sudden cardiac death or sustained monomorphic ventricular tachycardia. Results Mean age of our cohort was 61 years (standard deviation 14.5), and 64.2% were male. Median follow-up was 41 (interquartile range 26-62) months. LGE was present in 96 (55.2%) patients of our cohort (LGE+), and a high risk LGE pattern was found in 41 (42.7% of all LGE+ patients). LGE was more frequently located in the basal segments (78.6%). Mid-wall septal LGE was found in 46.9% of LGE+ patients, and it was the most common pattern. 21.4% of LGE+ patients had combined septal and free-wall LGE, 23.5% had epicardial LGE and 13.3% had transmural LGE. Baseline characteristics of LGE+ patients with and without a high-risk LGE pattern are shown at the Table. The incidence of ventricular arrhythmic events during follow-up was 31.7% in patients with a high-risk LGE pattern, and 9.1% in LGE+ patients but without a high-risk pattern (p=0.005). In patients without a high-risk LGE, including LGE- patients and LGE+ patients with other LGE patterns, incidence of ventricular arrhythmic events was 8.3% (p<0.001). The survival free curves for the combined arrhythmic endpoint comparing LGE+ patients with and without a high-risk pattern are shown in the Figure. Conclusion The presence of a high-risk LGE pattern in patients with DCM its associated with a higher incidence of ventricular arrhythmic events, comparing with LGE+ patients without a high-risk pattern. We suggest that this high-risk pattern should be taken into account when performing arrhythmic risk stratification in patients with DCM.TableFigure