Association between severity of cardiac dysfunction caused by ventricular pre-excitation-led dyssynchrony and cardiac function recovery after ablation in children.

OBJECTIVE: To investigate the association between the severity of cardiac dysfunction caused by ventricular pre-excitation-led dyssynchrony and cardiac function recovery time after catheter ablation and identify predictors of cardiac function recovery after ablation. METHODS AND RESULTS: A total of 49 children underwent successful ablation (median 2.92 years).This study included 23 patients with mild cardiac dysfunction (left ventricular ejection fraction [LVEF], 45 12 months, respectively. The mean LVEF of children with severe cardiac dysfunction aged 6 years did not normalize at 12 months of follow-up (38.67+/-10.97%). LVEF recovery time was significantly different between these two age groups (median 11 months vs > 12 months; chi2=4.55; P=0.04). Cox regression analysis showed that pre-ablation smaller left ventricular diastolic diameter (LVDd) Z score and higher LVEF were predictors of cardiac dysfunction recovery time (hazard ration [HR]=0.91, 95% confidence interval [CI]=0.82-0.99, P=0.04; HR=1.09, 95% CI=1.03-1.15,P=0.01). CONCLUSION: Patients with higher LVDd Z scores and lower LVEF tend to have slower improvement in cardiac function after ablation. Patients with LVEF 6 years need >12 months to fully recover, and some might not even completely recover. Early catheter ablation is suggested once ventricular pre-excitation-led cardiac dysfunction is suspected. This article is protected by copyright. All rights reserved.