Exercise Stress Test Late after Arrhythmic versus Nonarrhythmic Presentation of Myocarditis

Abstract

Background. Exercise stress test (EST) has been scarcely investigated in patients with arrhythmic myocarditis. Objectives. To report the results of EST late after myocarditis with arrhythmic vs. nonarrhythmic presentation. Methods. We enrolled consecutive adult patients with EST performed at least six months after acute myocarditis was diagnosed using gold-standard techniques. Patients with ventricular arrhythmia (VA) at presentation were compared with the nonarrhythmic group. Adverse events occurring during follow-up after EST included cardiac death, disease-related rehospitalization, malignant VA, and proven active myocarditis. Results. The study cohort was composed of 128 patients (age 41 ± 9 y, 70% males) undergoing EST after myocarditis. Of them, 64 (50%) had arrhythmic presentation. EST was performed after 15 ± 4 months from initial diagnosis, and was conducted on betablockers in 75 cases (59%). During EST, VA were more common in the arrhythmic group (43 vs. 4, p p = 0.115). By 58-month mean follow-up, 52 patients (41%) experienced adverse events, with a greater prevalence among arrhythmic patients (39 vs. 13, p p Conclusions. Late after the arrhythmic presentation of myocarditis, EST was frequently associated with recurrent VA. In both arrhythmic and nonarrhythmic myocarditis, EST abnormalities correlated with subsequent adverse outcomes.

Keywords

• exercise stress test
• physical activity
• myocarditis
• ventricular arrhythmia
• cardiac magnetic resonance
• endomyocardial biopsy