Electrophysiological Characteristics and Outcomes of Radiofrequency Catheter Ablation of Atrial Flutter in Children with or Without Congenital Heart Disease

Mid-term outcomes after catheter ablation in patients with congenital heart disease

INTRODUCTION

Cardiac arrhythmias are a major concern in patients with CHD. The purpose of this study was to evaluate the long-term outcomes in patients with CHD submitted to catheter ablation.

MATERIALS AND METHODS

Observational retrospective study of patients with CHD referred for catheter ablation from January 2016 to December 2021 in a tertiary referral centre. Acute procedural endpoints and long-term outcomes were assessed.

RESULTS

A total of 44 ablation procedures were performed in 36 CHD patients (55% male, mean age 43 ±3 years). Fifty-four arrhythmias were ablated: 23 cavotricuspid isthmus atrial flutters, 10 atrial re-entrant tachycardias, eight focal atrial tachycardias, eight atrial fibrillations, three atrioventricular re-entrant tachycardias, and two ventricular tachycardias. During a median follow-up time of 37 months (interquartile range 12-51), freedom from arrhythmia recurrence was achieved in 93%, with 1.2 procedures per patient (18% with anti-arrhythmic drugs). There were no adverse events related to catheter ablation. No predictors of recurrence were identified.

CONCLUSION

In patients with CHD, catheter ablation presents a high mid-term efficacy while maintaining a safe profile.

Characteristics and Ablation Outcomes of Atrial Tachycardia in Patients with Prior Cardiac Surgery vs. Spontaneous Scars: Where Are the Differences?

(1) Background: Atrial scars play an important role in atrial tachycardia (AT). They can not only be found in patients with prior cardiac surgery (PCS) but also in patients without PCS or significant structural heart disease, in which case the scar is called a spontaneous scar (SS). This study aims to compare the characteristics, mechanisms and ablation outcomes of AT in patients with PCS and SS. (2) Methods: We retrospectively reviewed electrophysiological and ablative characteristics of ATs in 46 patients with PCS and 18 patients with SS. (3) Results: There were averages of 1.52 and 2.33 ATs per patient in the PCS group and SS group, respectively (p < 0.01). Cavo-tricuspid isthmus dependent atrial flutter (CTI-AFL) was presented in most patients in both groups (93.50% vs. 77.80%, p = 0.17), whereas the SS group had a higher occurrence of scar-mediated reentrant AT (SMAT) and focal AT (FAT) compared with the PCS group (88.90% vs. 39.10%, p < 0.01; 22.2% vs. 2.2%, p < 0.05). There were no significant differences in acute success rate between the two groups, whereas patients with SS had lower long-term success rate (87.0% vs. 61.1%, p < 0.05) and higher occurrence of sinus node dysfunction (SND) (4.3% vs. 22.2%, p < 0.05). (4) Conclusions: CTI-AFL is common in both patients with PCS and SS, and routine CTI ablation is recommended. Compared with patients with PCS, patients with SS have more ATs, especially with higher occurrence of SMAT and FAT, and had a lower long-term success rate and higher incidence of SND.