Late gadolinium enhancement as a predictor of functional recovery, need for defibrillator implantation and prognosis in non-ischemic dilated cardiomyopathy

Background Aim of the study was to investigate whether late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) predict reverse remodeling (RR) in non-ischemic dilated cardiomyopathy (NIDCM). Methods Seventy-one NIDCM patients (age 57 ± 14 years, 43 males, median left ventricular ejection fraction [LVEF] 35%, [interquartile range 27–41%]) with two CMR scans within 5 years were included. RR was defined as ≥ 10% reduction in left ventricular (LV) end-diastolic volume and ≥ 10% LVEF increase. The end-point was a composite of all-cause death, cardiovascular hospitalization or appropriate defibrillator discharge. LGE was assessed both visually and as percentage of LV mass (LGE%). Results LGE was present in 42 patients (59%). During the interval between the 2 CMR scans (median 28 [15–44] months), 22 patients (31%) displayed RR. LGE absence predicted RR irrespectively of baseline LV volumes and LVEF. Over a median 42[15–73]-month follow-up, the endpoint occurred in 36 patients (51%). LGE absence was associated with better prognosis (P = 0.043), with best quantitative LGE cut-point < 7% at ROC analysis (P = 0.017), but RR was the strongest prognostic predictor. Among 35 patients with baseline LVEF < 35%, 25 (69%) crossed the 35% LVEF threshold. Both LGE absence and quantitative LGE < 7% were associated with crossing of the 35% LVEF threshold for defibrillator implantation; patients with either LGE or quantitative LGE ≥ 7% had a worse prognosis. Conclusions In NIDCM, the absence of LGE at baseline CMR is associated with RR. When baseline LVEF is < 35%, LGE absence is associated with more frequent crossing of the 35% LVEF threshold for defibrillator implantation.