Outcome of ACHD patients with non-inducible versus inducible IART undergoing cavo-tricuspid isthmus ablation: the role of empiric ablation

Abstract

Background: Catheter ablation for supraventricular tachycardia (SVT) in adults with congenital heart disease (ACHD) is an important therapeutic option. Cavotricuspid isthmus (CTI) dependent intra-atrial re-entrant tachycardia (IART) is common. However, induction of sustained tachycardia at the time of ablation is not always possible. We hypothesised that performing an empiric CTI line in case of noninducibility leads to good outcomes.Objectives: Long-term outcomes of empiric versus entrained CTI ablation in CHD patients were examined.Methods: Retrospective, single-centre, case-control study over seven years.Arrhythmia free survival post empiric versus entrained CTI ablation were compared.Results: 87 CTI ablations were performed in 85 ACHD patients between 2010 and 2017. The mean age of the cohort was 43 years and 48% were men. Underlying etiology included ASD (31%), VSD (11.4%), AVSD (9.1%), AVR (4.8%), Fallot's tetralogy (18.4%), Ebstein's anomaly (2.3%), Fontan surgery (9.2%) and Mustard/Senning repair (13.8%). CTI dependent IART was entrained in 59 patients whereas it was non-inducible in 28. The latter had an empiric CTI-line ablation. 57% of procedures were performed without a general anaesthetic. There were no procedural complications. There was no significant difference in the mean procedure and fluoroscopy times between the groups (Empiric vs Entrained CTI; 169.1 vs 183.3 and 28.1 vs 19.9 min). After a mean follow-up of 21 months, arrhythmia-free survival was 64.3% versus 72.8% (p-value 0.44) in the empiric and entrained CTI groups. Conclusion:Long-term outcomes after empiric and entrained CTI line ablation for IART ACHD patients are comparable. This is a safe and effective therapeutic option.In the case of non-inducibility of IART, an empiric CTI line ablation should be performed in this cohort.

Different electrophysiological characteristics of cavo‐tricuspid isthmus dependent atrial flutter guided by robotic magnetic navigation in patients with and without prior cardiac surgery

“…In routine practice, empirical CTI ablation was adopted if the tachycardia was judged as typical CTI‐AFL by ECG analysis before procedure. Sawhney et al 18 has shown that long‐term outcomes (over 7 years) after empiric and entrained CTI ablation for CTI‐AFL are comparable. Hence, an empiric CTI line should be considered in the case of noninducibility of CTI‐AFL.…”

Right atrial collision time (RACT): A novel marker of propensity for typical atrial flutter

“…Whereas ablation of the flutter circuit is indicated in patients with documented AFL, it is often considered in those without a documented AFL history, but high risk of unrecognized AFL or development of AFL in the future 5 . The practice of empiric flutter ablation is employed to prevent symptomatic recurrence and attenuate stroke risk in a group that may eventually present with thromboembolic complications as the first indication of AFL 6,7 . A simple diagnostic maneuver to determine the existence of a potential AFL circuit, and therefore a risk of occult or future AFL, would be very useful.…”

“…5 The practice of empiric flutter ablation is employed to prevent symptomatic recurrence and attenuate stroke risk in a group that may eventually present with thromboembolic complications as the first indication of AFL. 6,7 A simple diagnostic maneuver to determine the existence of a potential AFL circuit, and therefore a risk of occult or future AFL, would be very useful. This could support the decision on whether to empirically ablate a flutter circuit at time of ablation for other rhythms, such as atrial fibrillation.…”