Atrial fibrillation (AF) may occurs in patients (pts) undergoing slow pathway ablation (SPA) for recurrent symptomatic AV node re-entry tachycardia (AVNRT). In some patients (pts), AF may develop later on. Pts undergoing SPA may continue to feel palpitations mostly due to atrial extra beats which can provoke AF.
Methods: We perform a retrospective analysis of 211 consecutive pts who underwent SPA in our department since 2008 to investigate the predictors for spontaneous AF occurrence after SP ablation.
Baseline characteristics: 61% women, mean age 54.2±14.5 years, mean left ventricular ejection fraction (LVEF) 65.1±7.9%, 32.7% with left atrial enlargement (LAE), 48% with hypertension (HTN), 8.5% after AF episodes and 6.6% with a history of valvular problems (VP).
Results: The success rate of SPA was 98.6%. There were no complications. During SPA AF occurs in 25 (11.8%) pts. During a follow up (FU) period of 34.7±21.9 month, 1.9% of the pts had a recurrences of AVNRT. Six patients underwent re-do procedures with 83% of success. 35.1% of the pts continued to experience palpitations. 13 pts (6.2%) developed AF 28±15 months after SPA. Pts who suffer from AF in FU period were significantly older(66.8±13.8 vs. 53.4±19.1 years old, p<0.001), with lower LVEF (57.3±11.9% vs. 65.7±7.4%, p<0.001), higher incidence of LAE (69% vs. 30%, p<0.002) and VP (23% vs. 5.6%, p<0.01). AF induction during SPA (38% vs. 10%, p<0.001) and postablation palpitations (69% vs. 34%, p<0.015) were strongly associated with late AF appearance. AH interval and slow pathway ERP were significantly longer among pts developed late AF, as well. History of previous AF had no predictive value for postablation AF.
Conclusions: In addition to traditional predictors for development of AF, we`ve found that AF during SPA and postablation palpitations predict late appearance of AF.
