Focal fibrosis and diffuse fibrosis are predictors of reversed left ventricular remodeling in patients with non-ischemic cardiomyopathy.

Background: Prognostic value of myocardial fibrosis in patients with non-ischemic idiopathic dilated cardiomyopathy (DCM) is not well-defined. We sought to assess the association of focal and diffuse myocardial fibrosis with left ventricular reversed remodeling (LVRR).

Methods: Patients with DCM who underwent cardiac MRI with baseline and subsequent follow-up echocardiography were included in the study. Post-contrast T1 times were corrected for renal function, body size, gadolinium dose and time after Gadolinium injection. Patients were followed over a median time of 29months to evaluate changes of left ventricular end-systolic volume (LVESV). A Linear Mixed Model was used to assess the relationship between the LVESV during follow-up, corrected post-T1 value delayed hyperenhancement (DHE), and modified Seattle Heart Failure Score (SHFS).

Results: A total of 103 patients (mean age 51±15years, 61% male) were evaluated. The mean LVEF was 33±11%, LVESVi 62±39ml/m(2), and T1 time 416±98. DHE was identified in 45 patients (44%). Patients with focal DHE (n=45) had higher LVESVi at baseline and during follow-up (p=0.024). Post T1 value >450 was an independent predictor of LVRR at the follow-up (Δ=24.6ml/m(2) SE 14.6ml/2, p=0.0480) in patients despite the presence of DHE, even after adjusting for their SHFS.

Conclusion: While DCM patients with focal DHE demonstrated greater adverse LV remodeling than those without focal fibrosis, diffuse fibrosis independently predicts LVRR in DCM patients in patients despite the presence of focal fibrosis.