Atrioventricular Nodal Reentrant Tachycardia in Patients With Congenital Heart Disease: Outcome After Catheter Ablation.

BACKGROUND The relationship of atrioventricular nodal reentrant tachycardia to congenital heart disease (CHD) and the outcome of catheter ablation in this population have not been studied adequately. METHODS AND RESULTS A multicenter retrospective study was performed on patients with CHD who had atrioventricular nodal reentrant tachycardia and were treated with catheter ablation. There were 109 patients (61 women), aged 22.1±13.4 years. The majority, 86 of 109 (79%), had CHD resulting in right heart pressure or volume overload. Patients were divided into 2 groups: group A (n=51) with complex CHD and group B (n=58) with simple CHD. There were no significant differences between groups in patients' growth parameters, use of 3-dimensional imaging, and type of ablation (radiofrequency versus cryoablation). Procedure times (251±117 versus 174±94 minutes; P=0.0006) and fluoroscopy times (median 20.8 versus 16.6 minutes; P=0.037) were longer in group A versus group B. There were significant differences between groups in the acute success of ablation (82% versus 97%; P=0.04), risk of atrioventricular block (14 versus 0%; P=0.004), and need for chronic pacing (10% versus 0%; P=0.008). There was no permanent atrioventricular block in patients who underwent cryoablation. After 3.2±2.7 years of follow-up, long-term success was 86% in group A and 100% in group B (P=0.004). CONCLUSIONS Atrioventricular nodal reentrant tachycardia can complicate the course of patients with CHD. This study demonstrates that the outcome of catheter ablation is favorable in patients with simple CHD. Patients with complex CHD have increased risk of procedural failure and atrioventricular block.