[Atrial insertion of accessory pathways in permanent reciprocating junctional tachycardia]

Permanent reciprocating junctional tachycardia (PRJT) is an uncommon type of Tachycardia, usually associated with a retrogradely conducting accessory pathway situated near to the ostium of the coronary sinus. This study reports the localisation of the site of atrial insertion of the accessory pathway, confirmed by the efficacy of intracardiac catheter ablation. Five patients (4 men), aged 14 to 45, experienced PRTJT at rates of 120 to 150/mn over a period of 2 to 15 years. 4 patients were normal, expected in 2 patients in whom they were 16 and 20%. One of these suffered a thromboembolic complication after pharmacological interruption of the tachycardia. The presence of an accessory pathway with decremential retrograde conduction was confirmed in all cases. Catheter ablation was successful in the medio-septal (2 cases), posteroseptal (1 case), lateral (1 case) and anteroseptal (1 case) regions. Six to 30 applications of 20 to 30 watts of radiofrequency energy were used in the 5 cases. In one case (right lateral accessory pathway), a fulguration procedure was necessary with a cathodic shock of 160 Joules. The AV conduction was preserved and retrograde conduction was normalised in all cases. All patients remained asymptomatic for a period of 10 to 43 months without antiarrhythmic therapy. The ejection fractions of the two patients with left ventricular dysfunction returned to normal. The authors conclude that the accessory pathways of PRJT may be situated in different regions of the right atrium. The efficacy of catheter ablation was 100 % in this form of tachycardia.