Posteroseptal accessory pathway in association with coronary sinus diverticulum: electrocardiographic description and result of catheter ablation

A precise knowledge of the coronary sinus (CS) anatomy and its potential anomalies seems essential to increase the rate of success in patients with a prior history of multiple ablation failures of the posteroseptal accessory pathway or in whom this procedure cannot be performed easily. We aimed to describe the anatomic and electrocardiographic characteristics of the CS diverticulum in association with the posteroseptal accessory pathway and subsequent catheter ablation results. We retrospectively recruited 12 patients with posteroseptal accessory pathways associated with CS diverticula from patients referred to Tehran Heart Center for electrophysiological study and ablation between January 2004 and December 2011. The study population consisted of eight males and four females at a mean age of 48.2 +/- 17.5 years with posteroseptal accessory pathways. The most frequent initial presentation was orthodromic atrioventricular re-entrant tachycardia and atrial fibrillation. The rate of acute success for radiofrequency ablation and the recurrence rate were 75 and 16.6 %, respectively. Larger diverticula tended to have more failure and recurrence rate, albeit not significant. None of the patient's characteristics could significantly predict the success of the ablation. Our total initial failure rate and subsequent recurrence was around 41 %. Better results might have been achieved had we applied irrigated tip catheters or NavX(TM)-guided cryoablation or subxiphoid epicardial mapping and ablation.