Abstract 14098: Incidence and Characteristics of Tachyarrhythmias in Pediatric Patients with Acute Myocarditis
Introduction: Acute myocarditis may be associated with life threatening tachyarrhythmias and a poor outcome. The purpose of this study was to define the incidence and clinical characteristics of tachyarrhythmias in pediatric patients with acute myocarditis.
Methods: We retrospectively reviewed all patients ≤ 21 years of age who received a clinical or biopsy proven diagnosis of acute myocarditis from 1/05-7/11 at a tertiary care institution. Clinically significant tachyarrhythmias (CSTs) were defined as requiring treatment with antiarrhythmic medications. Logistic regression was used for statistical analysis. P<0.05 was considered statistically significant.
Results: 71 patients met the inclusion criteria (63% male, 12.4 ± 6.5 years; 52.1 ± 30 kg). The diagnosis of myocarditis was made clinically with 23% (n=16) confirmed with biopsy. Twenty-seven (38%) patients required intubation and 36 (51%) were treated with inotropes. There were 17 patients with CSTs (3 supraventricular, 3 non-sustained VT, 11 sustained VT/VF). Cardioversion or defibrillation was required in 9/17 (53%). Patients with CSTs were more likely to have been treated with inotropes (16/17, 94%) than those without tachyarrhythmias (19/54, 35%) (p < 0.01). Fifteen patients required mechanical support (21%). Patients with CSTs were more likely to require mechanical support (9/17, 53%) as compared to patients without (6/54, 11%) (p < 0.01). Three patients were transplanted and four died (7/72, 10%). Patients with CSTs were more likely to experience death or transplant (DOT) (5/17, 29%) as compared to patients without CSTs (2/54, 4%) (p < 0.01). When controlling for age and shortening fraction (SF) CSTs remain a predictor of DOT (OR 7.4, CI 1.1-49.8, P = 0.04). Shortening fraction was an independent predictors of CSTs, while gender, CRP, ESR, and troponins were not.
Conclusion: Pediatric patients with acute myocarditis have a considerable incidence of clinically significant tachyarrhythmias. The morbidity and mortality is significantly higher in patients with tachyarrhythmias.
- © 2012 by American Heart Association, Inc.