Abstract:

Objective To illustrate the clinical features, efficiency of anti-arrhythmic medications and prognosis in pediatric tachycardia-induced cardiomyopathy (TIC) . Methods Retrospective review of medical records was carried out in children with TIC, and defined as LVFS <30% associated with various tachyarrhythmia in Children′s Hospital of Fudan University. Data with respect to the clinical findings, anti-arrhythmic therapy, electrocardiographic and echocardiographic evaluation and biomarkers were collected. Clinical follow-up was continued until both LVFS≥30% and Z-LVEDD>2.0 were achieved. Multivariate linear and logistic regression analysis was performed to evaluate possible predictors of time to myocardial recovery. Results A total of 56 pediatric cases with TIC were included in our study from May 2003 to January 2016. Forty patients （71.4%）were infants and 37 were boys (66.1%). Atrial tachycardia and paroxysmal supraventricular tachycardia were the most common types of responsible tachyarrhythmia, with the percentage of 53.6% and 37.5%, respectively. Anti-arrhythmic medications as part of management were used in all 56 cases and complete, partial and none effective response to medications occurred in 29 (51.8%), 23 (41.1%) and 4 (7.1%) cases, respectively. Amiodarone was the most commonly used medication, and its effectiveness was achieved in 92.3% (36/39) children, including both used alone and in combination with other medications. Except for 2 cases of death, left ventricular fractional shortening (LVFS) was significantly increased from (23.7±3.7)% to (32.8±4.6)% (P<0.001), and Z-LVEDD was decreased from (2.79±3.04) to (0.37±2.0) ( P<0.001) in the remaining 54 cases. Median time for recovery of LVFS and Z-LVEDD was 10 days and 42 days, respectively. Plasma (N-terminal) pro B-type natriuretic peptide was reduced significantly from (15 711±11 453) pg·mL-1 to (1 287±1 510) pg·mL-1 (P<0.001). Predictor of earlier left ventricular size normalization was smaller baseline Z-LVEDD (β=0.528，95%CI：0.127-0.506，P=0.002). Conclusion Myocardial dysfunction is wholly or partially reversible after control of the responsible tachyarrhythmia in pediatric TIC. Early recognition and treatment by clinicians are crucial for favorable recovery of left ventricular function.