2424Long-term outcome of patients with biopsy-proven viral myocarditis: 12-year results from a late gadolinium enhancement cardiac magnetic resonance study

Abstract Purpose Myocarditis is a common cardiac disease that is associated with significant mortality as demonstrated by several studies. Late gadolinium enhancement (LGE) by cardiac magnetic resonance imaging (CMR) is a valuable tool for risk stratification of patients with suspected myocarditis. Previous studies using CMR-LGE have reported a good negative predictive value over follow-up periods of 4–6 years, while its positive predictive value was only modest. However, there is a lack of data regarding the long-term prognosis (>10 years) of these patients. This study reports an extended long-term follow-up of a large cohort of patients with biopsy-proven viral myocarditis. Methods At initial presentation, all patients underwent endomyocardial biopsy and CMR for the work-up of suspected myocarditis or unclear cardiomyopathy and had evidence of virus in PCR analyses. The primary endpoints were: all-cause death, cardiac death, and the occurrence of sudden cardiac death (SCD). Results 183 patients with biopsy-proven viral myocarditis were followed for a median of 11.5 years. At baseline, patients were 52 years old, 31% were females, and the median ejection fraction was moderately reduced (44%). Initial CMR assessment revealed LGE in 101 (55%) patients, while 82 (45%) patients had LGE-negative CMR. During the follow-up period, the following endpoints occurred in the overall cohort: all-cause death (n=71, 39%), cardiac death (n=50, 27%) and SCD (n=20, 11%). Most importantly, only a single LGE-negative patient experienced a SCD during this 12-year follow-up, while all other SCDs occurred in patients with LGE-positive CMR (1% vs. 19%, p<0.001). Consequently, the negative predictive value (NPV) of normal CMR-LGE regarding SCD was 98%. In addition, cardiac mortality (12% vs. 40%, p<0.001, NPV=88%) and all-cause mortality (20% vs. 54%, p<0.001, NPV=79%) were significantly lower in patients without LGE. Conclusion This cohort of biopsy-proven viral myocarditis demonstrates substantial mortality (39% in 11.5 years). However, absence of LGE on CMR was associated with favorable prognosis. This was applicable regarding all-cause and cardiac mortality, but most importantly with regard to SCD with a NPV of 98% over almost 12 years median follow-up. Acknowledgement/Funding This work was funded by the Robert-Bosch-Stiftung, Stuttgart, Germany and the Berthold-Leibinger-Stiftung, Ditzingen, Germany.