Late gadolinium enhancement distribution patterns in non-ischemic dilated cardiomyopathy: Genotype-phenotype correlation.

Abstract

AIMS Late gadolinium enhancement (LGE) is frequently found in patients with dilated cardiomyopathy (DCM), there is little information about its frequency and distribution pattern according to underlying genetic substrate. We sought to describe LGE patterns according to genotype and to analyze the risk of major ventricular arrhythmias (MVA) according to patterns. METHODS AND RESULTS Cardiac magnetic resonance findings and LGE distribution according to genetics was performed in a cohort of 600 DCM patients followed at 20 Spanish centers. After exclusion of individuals with multiple causative gene variants or with variants in infrequent DCM-causing genes, 577 patients (34% females, mean age 53.5 years, LVEF 36.9 ± 13.9%) conformed the final cohort. A causative genetic variant was identified in 219 (38%) patients and 147 (25.5%) had LGE. Significant differences were found comparing LGE patterns between genes (P < 0.001). LGE was absent or rare in patients with variants in TNNT2, RBM20 and MYH7 (0%, 5% and 20%, respectively). Patients with variants in DMD, DSP and FLNC showed predominance of LGE subepicardial pattern (50%, 41% and 18%, respectively) whereas patients with variants in TTN, BAG3, LMNA and MYBPC3 showed unspecific LGE patterns. Genetic yield differed according to LGE pattern. Patients with subepicardial, lineal midwall, transmural, right ventricular insertion points or with combination of LGE patterns showed increased risk of MVA compared with patients without LGE. CONCLUSION LGE patterns in DCM has a specific distribution according to the affected gene. Certain LGE patterns are associated with increased risk of MVA and with increased yield of genetic testing.