LONG-TERM FOLLOW-UP IN PATIENTS WITH THE PERMANENT FORM OF JUNCTIONALRECIPROCATING TACHYCARDIA TREATED WITH RADIOFREQUENCY ABLATION

This study sought to determine the longterm follow-up, safety, and eff icacy of radiofrequency catheter ablation of patients with the permane nt form of junctional reciprocating tachycardia (PJRT). We assessed th e reversibility of tachycardia induced LV dysfunction and we detailed the location and electrophysiological characteristics of these retrogr ade atrioventricular decremental pathways. PJRT is an infrequent form of reciprocating tachycardia, commonly incessant, and usually drug ref ractory. The ECG hallmarks include an RP interval > PR with inverted P waves in leads II, III, aVF, and V-3-V-6. During tachycardia, retrogr ade VA conduction occurs over an accessory pathway with slow and decre mental conduction properties, located predominantly in the posterosept al zone. It is known that long-lasting and incessant tachycardia mail result in tachycardia induced severe ventricular dysfunction. We inclu ded 36 patients (13 men, 23 women, mean +/- SD, aged 44 +/- 22 years) with the diagnosis of PJRT. Seven patients had tachycardia induced lef t ventricular dysfunction. Radiofrequency energy was delivered at the site of earliest retrograde atrial activation during ventricular pacin g or during reciprocating tachycardia. All patients were followed at t he outpatient clin ic and serial echocardiograms were performed in tho se who presented with depressed LV function. Radiofrequency ablation w as performed in 36 decremental accessory pathways. Earliest retrograde atrial activation was right posteroseptal in 32 patients (88%), right mid-septal in 2 (6%), right posterolateral in 1 (3%), and left antero lateral in 1 (3%). Thirty-five accessory pathways were successfully ab lated with a mean of 5 +/- 3 applications. A mid-septal accessory path way could not be ablated. After a mean follow-up of 21 +/- 16 months ( range 1-64) 34 patients are asymptomatic. There were recurrences in 8 patients after the initial successful ablation (mean of 1.2 months), 5 were ablated in a second ablation procedure, 2 patients required a th ird procedure, and 2 patient required four ablation sessions. All pati ents with LV dysfunction experienced a remarkable improvement after ab lation. Mean preablation LV ejection fraction in patients with tachyca rdiomyopathy was 28% +/- 6% and rose to 51% +/- 16% after ablation (P < 0.02). Our study supports the concept that radiofrequency catheter a blation is a safe and effective treatment for patients with PJRT. Radi ofrequency ablation should be the treatment of choice in these patient s because this arrhythmia is usually drug refractory. The majority of accessory pathways are located in the posteroseptal zone. Cessation of the arrhythmia after successful ablation results in recovery of LV dy sfunction.