Prevalence and Prognostic Impact of Septal Late Gadolinium Enhancement in Acute Myocarditis With or Without Preserved Left Ventricular Function.

Recent data suggest that myocardial septal late gadolinium enhancement (LGE) may have an independent prognostic value in patients with acute myocarditis undergoing cardiac magnetic resonance (CMR). Aim of the present study is to evaluate its prevalence and prognostic implications in these patients with or without preserved LV function. Retrospective cohort study including all cases of clinically suspected acute myocarditis referred for CMR. A diagnosis of acute myocarditis was confirmed by CMR according to Lake Louise Criteria. Cardiovascular mortality, heart failure, heart transplantation, and sustained ventricular arrhythmias were considered adverse events at follow-up. Seventy-one patients were included in the present study (mean age 47 years 95% confidence intervals 42 to 51, 53 males; 75%). Left Ventricular Ejection Fraction (LVEF) was preserved in 45 cases (63%) and pericardial effusion was detected in 26 cases (38%). CMR was performed at a mean time of 11 days (95% confidence intervals 7.5 to 14.4) from symptoms onset. Myocardial hyperemia and edema were detected in 53 cases (75%), myocardial LGE in 66 cases (93%). Septal LGE was reported in 21 cases (30%). After a mean follow-up of 60.8 months, the mean LVEF increased from 51.6 ± 14.0% to 56.6 ± 10.9% (p = 0.021) and combined adverse events were only recorded in 4 patients (6%) with reduced basal LVEF. These patients had more commonly septal LGE (respectively 58% vs13%, p <0.0001). However, on multivariable analysis septal LGE had no additional predictive value over reduced basal LVEF. In conclusion, our study suggests that septal LGE is not uncommon in patients with acute myocarditis but has no added prognostic value over reduced LVEF at presentation.