FAST PATHWAY ABLATION IN PATIENTS WITH COMMON ATRIOVENTRICULAR NODAL REENTRANT TACHYCARDIA AND PROLONGED PR INTERVAL DURING SINUS RHYTHM

Aims This study aimed to clarify the safety and efficacy of selective fast pathway ablation in patients with atrioventricular nodal reentran t tachycardia and a prolonged PR interval during sinus rhythm. Such pa tients have been reported to have an increased incidence of complete a trioventricular block. Methods and Results In this study, the earliest retrograde atrial activation during atrioventricular nodal reentrant tachycardia and right ventricular stimulation was localized. Fast path way ablation was then performed in five patients with the common form of atrioventricular nodal reentrant tachycardia and a prolonged PR int erval. Three of the five patients had almost incessant atrioventricula r nodal reentrant tachycardia. Radiofrequency catheter ablation induce d a complete ventriculo-atrial block during right ventricular stimulat ion in four patients and a marked prolongation of ventriculo-atrial co nduction during right ventricular stimulation in one. Non-inducibility of common atrioventricular nodal reentrant tachycardia with and witho ut isoproterenol was achieved in all five patients. The PR atrio-His i nterval from 172+/-46ms to 192+/-45 ms. Second-or third-degree atriove ntricular block did not occur during the ablation procedure. During th e followup of 19+/-20 months none of the patients developed symptoms s uggestive of atrioventricular nodal reentrant tachycardia or evidence of second-or third-degree atrioventricular block. Conclusion These dat a suggest that atrioventricular node (retrograde) fast pathway ablatio n can apparently be safely performed in patients with common atriovent ricular nodal reentrant tachycardia and a prolonged PR interval during sinus rhythm.