Bezold-Jarisch-like reflex during radiofrequency ablation of the pulmonaryvein tissues in patients with paroxysmal focal atrial fibrillation

Introduction: Information is lacking about the occurrence of ablation-relat ed proarrhythmic events during application of radiofrequency (RF) energy at the pulmonary veins in patients with paroxysmal focal atrial fibrillation. The purpose of this study was to assess the theoretical risk of reflex bra dycardia and hypotension response during RF ablation of these regions rich in endocardial nerve terminals. Methods and Results: Among the 40 consecutive patients (29 men, 11 women; m ean age 65 +/- 12 years) with clinically documented frequent attacks of par oxysmal atrial fibrillation who underwent superior pulmonary vein ablation for left focal atrial fibrillation, 6 patients (15%) developed bradycardia- hypotension syndrome during energy delivery. A single atrial fibrillation t rigger focus in the left or right superior pulmonary vein was found in 3 an d 1 patients, respectively. Two patients had two trigger foci originating f rom the orifice or proximal part of both superior pulmonary veins. After RF current was applied for a period of 14 +/- 10 seconds, 2 patients develope d junctional rhythm and sinus bradycardia, another 2 patients had profound sinus bradycardia, 1 patient had two episodes of sudden onset of complete A V block with resultant 9.5-second asystole, and 1 patient showed profound s inus bradycardia, transient AV block, and an 8-second asystole due to sinus arrest. Blood pressure fell when any substantial bradyarrhythmias occurred . All 6 patients were free of rhythm disturbances during the postablation f ollow-up period (mean 8 +/- 2 months). Conclusion: RF catheter ablation of the pulmonary vein tissues could evoke a variety of profound bradycardia-hypotension responses. The Bezold-Jarisch -like reflex might be the underlying mechanism.