Predictors of Mortality in Patients With Biopsy-Proven Viral Myocarditis: 10-Year Outcome Data

Background There is scarce data about the long-term mortality as well as the prognostic value of cardiovascular magnetic resonance and late gadolinium enhancement (LGE) in patients with biopsy-proven viral myocarditis. We sought to investigate: (1) mortality and (2) prognostic value of LGEcardiovascular magnetic resonance (location, pattern, extent, and distribution) in a >10-year follow-up in patients with biopsy-proven myocarditis. Methods and Results Two-hundred three consecutive patients with biopsy-proven viral myocarditis and cardiovascular magnetic resonance were enrolled; 183 patients were eligible for standardized follow-up. The median follow-up was 10.1 years. End points were all-cause death, cardiac death, and sudden cardiac death (SCD). We found substantial long-term mortality in patients with biopsy-proven myocarditis (39.3% all cause, 27.3% cardiac, and 10.9% SCD); 101 patients (55.2%) demonstrated LGE. The presence of LGE was associated with a more than a doubled risk of death (hazard ratio [HR], 2.40; 95% CI], 1.30-4.43), escalating to a HR of 3.00 (95% CI, 1.41-6.42) for cardiac death, and a HR of 14.79 (95% CI, 1.95-112.00) for SCD; all P <= 0.009. Specifically, midwall, (antero-) septal LGE, and extent of LGE were highly associated with death, all P<0.001. Septal LGE was the best independent predictor for SCD (HR, 4.59; 95% CI, 1.38-15.24; P=0.01). Conclusions In patients with biopsy-proven viral myocarditis, the presence of midwall LGE in the (antero-) septal segments is associated with a higher rate of mortality (including SCD) compared with absent LGE or other LGE patterns, underlining the prognostic benefit of a distinct LGE analysis in these patients.