Long-term efficacy of catheter ablation for reentrant atrial tachycardia in dextro-transposition of the great arteries patients after atrial switch
T Gonzalez Ferrero, C Alvarez Ortega, S Gonzalez Estriegana, J Ruiz Cantador, P Meras Colunga, C Merino Argos, N Gutierrez Ruiz, J Diz Diaz, R Moreno Gomez, R Peinado PeinadoAbstract
Background
Reentrant atrial tachycardias (ATs) are frequent after atrial switch for dextro-transposition of the great arteries (D-TGA) and are associated with adverse prognosis. Catheter ablation (CA) is first-line therapy, yet long-term outcomes and predictors of recurrence remain poorly defined.
Objectives
To characterize induced AT circuits, describe acute and long-term CA outcomes, and identify recurrence predictors in D-TGA.
Methods
Single-center ambispective cohort of consecutive D-TGA adults undergoing a first AT ablation (2003–2025). Arrhythmias were mechanically induced with decremental pacing or extra stimuli. Acute success was defined as elimination of all clinical and reproducibly inducible tachycardias (cycle length >200 ms), with bidirectional CTI block when applicable. Recurrence was any documented atrial tachycardia >30 seconds.
Results
Thirty-three patients underwent 46 procedures. During the index procedure, 66 RATs were induced, 51 (83%) characterized: 32 (63%) were cavotricuspid isthmus (CTI)-dependent and 11 (22%) incisional. CTI block was achieved in 84%; acute non-inducibility in 73%. Median follow-up was 7.0 years [IQR 2.5–10.4]. Overall, 15 patients (45.5%) recurred; 1-year freedom was 75%. Recurrence was strongly associated with failed or uncertain acute efficacy, severely impaired systemic RV fractional shortening ≤22%, prolonged or unmeasurable PR interval, and greater number of inducible ATs (all p<0.05). In multivariable modelling, these four variables yielded an optimism-corrected C-index of 0.838. Eleven (33%) underwent redo ablation; 8 achieved acute non-inducibility and only 3 recurred thereafter.
Conclusions
In D-TGA post-atrial switch, CTI-dependent flutter is most common, but scar-related circuits are frequent. CA is safe and acutely effective, but long-term recurrence remains substantial. Failed acute efficacy, severely impaired systemic RV contractility, prolonged PR interval, and multiple inducible RATs identify patients at highest risk and may guide follow-up and referral for early repeat ablation.Central IllustrationKM AT recurrence-free survival