Late gadolinium enhancement for re‐worsening left ventricular ejection fraction in patients with dilated cardiomyopathy

AIMS: This study aimed to evaluate the clinical parameters including late gadolinium enhancement (LGE) of cardiovascular magnetic resonance to predict re‐worsening of left ventricular ejection fraction (LVEF) in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: We included 138 patients with recent‐onset DCM who had an LVEF <45% and underwent LGE of cardiovascular magnetic resonance imaging at diagnosis and echocardiography at the yearly follow‐up [median 6 (4–8.3) years]. Initial LVEF recovery was defined as LVEF increase >10% from baseline, resulting in LVEF ≧45% after treatment. The patients were divided into three groups: (i) improved (n = 83, 60%), defined as those with sustained LVEF ≧45%; (ii) re‐worsening (n = 39, 28%), those with >5% decrease and LVEF <45% after the initial LVEF recovery; and (iii) not‐improved (n = 16, 12%), those without initial LVEF recovery. The primary endpoint was a composite of hospitalization for heart failure or sudden cardiac death. In baseline, LGE was observed in 70 patients. The LGE area was significantly larger in the re‐worsening and not‐improved groups than that in the improved group (P < 0.001). Loess curves of long‐term LVEF trajectories showed that LVEF in the re‐worsening group increased in the first 2 years and slowly declined thereafter. Multivariate logistic regression analysis demonstrated that LGE area [odds ratio (OR) 1.09, 95% confidence interval (CI) 1.03–1.16, P = 0.004], B‐type natriuretic peptide (OR 1.49, 95% CI 1.05–2.21, P = 0.030) level at the initial recovery, and LVEF (OR 0.91, 95% CI 0.86–0.97, P = 0.004) at the initial LVEF recovery were independent predictors of re‐worsening of LVEF. During a median follow‐up of 2273 (interquartile range: 1634–3191) days, the primary endpoint was observed in 31 (22%) patients. Univariate Cox proportional hazards analysis demonstrated that the risk of experiencing the primary event in the re‐worsening group was significantly higher (hazard ratio: 4.30, 95% CI 1.63–11.31, P = 0.003) than that in the improved group and was lower than that in the not‐improved group (hazard ratio: 0.33, 95% CI 0.15–0.72, P = 0.006). CONCLUSIONS: Re‐worsening of LVEF was observed in 28% of patients with recent‐onset DCM who showed an initial improvement in LVEF. High LGE burden, higher B‐type natriuretic peptide level, and lower LVEF at the initial LVEF recovery were independent predictors of re‐worsening of LVEF in patients with DCM. Careful observation is recommended for patients with a high risk for re‐worsening of LVEF, even in those with an initial LVEF recovery.