Re-worsening Left Ventricular Function Is Associated with Cardiac Fibrosis in Patients with Dilated Cardiomyopathy

Background: It is unclear that the clinical significance and clinical variables associated with re-worsening left ventricular (LV) function (RWLF) in patients with dilated cardiomyopathy (DCM) after pharmacotherapy. Methods and Results: Seventy newly-diagnosed DCM patients who underwent cardiac magnetic resonance late gadolinium enhancement (LGE) and increased in LV ejection fraction (EF) of >10% after 12 months only pharmacotherapy were enrolled. Echocardiography was performed at 6, 12, 24, and 36 months. RWLF, defined as decreased LVEF of >10% after 24 months, was shown in 5 (7%) patients. Although there were no significant difference both baseline LVEF (31 ± 8% vs 31 ± 8%, P = .97) and LVEF after 12 months pharmacotherapy (54.9 ± 14% vs 54.6 ± 9.1%, P = .96) between the RWLF+ and RWLF- groups, LVEF in RWLF+ groups was gradually declined. After 36 months, LVEF in RWLF+ groups was significantly lower than that in RWLF patients (43.4 ± 13.8% vs 54.6 ± 9.1%, P < .01). Cardiac death, defined as sudden death and pump failure death, was observed in 3 (4%) patients following 38 ± 23 months after 36 months pharmacotherapy. Kaplan-Meier analysis indicated that RWLF+ was significantly associated with cardiac death (P < .0001). Both the ratio of LGE positive patients (5/5;100% vs 26/39;40%, P = .014) and the extent of LGE (14.8 ± 5.5% vs 6.5 ± 3.7%, P = .0003) were significantly higher in RWLF+ groups than in RWLF- groups. Conclusions: RWLF is associated with cardiac fibrosis, showing poor cardiac outcome in patients with DCM.