Characterization and long-term outcomes of patients with myocarditis: a retrospective observational study

Introduction
There is limited data on the long-term follow-up of patients with myocarditis. Aim: To investigate the long-term follow-up of patients with myocarditis.

Material and methods
We performed a retrospective observational analysis on the clinical long-term outcomes of patients with myocarditis over a 10-year period. The primary outcome was mortality. We identified risk factors for mortality and adverse clinical outcomes. We also compared the characteristics and outcomes of patients presenting with fulminant myocarditis to those presenting with non-fulminant myocarditis.

Results
Between May 2004 and December 2014, 203 patients with myocarditis or perimyocarditis were admitted to our center. Most patients were male (87.7%) with a median age at presentation of 33 years (interquartile range: 25.4–38.9). The median follow-up period was 56.9 months (interquartile range 25.3–87.3 months), during which the overall mortality was 4.4% (9 patients). Fifteen patients presented with fulminant myocarditis. After multivariable analysis, older age (HR = 1.11, 95% CI: 1.05–1.16, p < 0.001) and a poorer New York Heart Association (NYHA) function class (HR = 4.6, 95% CI: 1.18–18, p = 0.028) were found to be independently associated with a higher risk of mortality, whereas higher albumin levels at presentation (HR = 0.2, 95% CI: 0.07–0.56, p = 0.002) were associated with decreased mortality. The group presenting with fulminant myocarditis had a more severe course of disease and a higher in-hospital mortality (13.3% vs. 0%, p = 0.005).

Conclusions
The overall prognosis of patients with myocarditis is good – in terms of both survival and recovery without residual left ventricular dysfunction.