Posteroseptal accessory pathway in association with coronary sinus diverticulum: electrocardiographic description and result of catheter ablation Babak Payami & Akbar Shafiee & Maryam Shahrzad & Ali Kazemisaeed & Gholamreza Davoodi & Ahmad Yaminisharif Received: 23 September 2012 / Accepted: 26 December 2012 / Published online: 8 February 2013 # Springer Science+Business Media New York 2013 Abstract Aims A precise knowledge of the coronary sinus (CS) anat- omy 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 cathe- ter ablation results. Methods We retrospectively recruited 12 patients with post- eroseptal accessory pathways associated with CS diverticula from patients referred to Tehran Heart Center for electro- physiological study and ablation between January 2004 and December 2011. Results The study population consisted of eight males and four females at a mean age of 48.2±17.5 years with poster- oseptal accessory pathways. The most frequent initial pre- sentation 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. Conclusion Our total initial failure rate and subsequent recur- rence was around 41 %. Better results might have been achieved had we applied irrigated tip catheters or NavX TM -guided cryoa- blation or subxiphoid epicardial mapping and ablation. Keywords Coronary sinus . Diverticulum . Radiofrequency catheter ablation . Accessory pathway 1 Introduction Radiofrequency (RF) catheter ablation is deemed a treat- ment of choice in patients with Wolff–Parkinson–White syndrome [1–3] and is shown to have a success rate of 95 % in some series [4]. Posteroseptal accessory pathways are, however, sometimes difficult to interrupt due to the complexity of their anatomical arrangements [1, 4, 5]. Posteroseptal accessory pathways are correlated with the coronary sinus (CS) diverticula in 10 % of patients, who are liable to have a higher risk of sudden cardiac death (4) because of probable accessory pathway conduction during atrial fibrillation and significant ablation failure [1]. These venous anomalies mostly arise 1.5 cm away from the CS and before the middle cardiac vein, but they can originate from the middle or posterior cardiac veins as well [6]. An extension of the CS myocardial coat through the pos- terior coronary vein, the middle cardiac vein, or a diverticulum neck and its connection with the left ventricular epicardium can form an epicardial posteroseptal accessory pathway, which is not amenable to ablation [1, 7]. As a result, a successful ablation site in patients with overt posteroseptal accessory pathways and the CS diverticula seems to be epi- cardial and, specifically, in the diverticulum neck [4, 8]. For an exploration of the CS anatomy, surface electrocardiography (ECG) can be drawn upon to determine the epicardial location B. Payami : A. Kazemisaeed : G. Davoodi : A. Yaminisharif (*) Department of Cardiac Electrophysiology, Tehran Heart Center, Tehran University of Medical Sciences, North Kargar Ave., 1411713138, Tehran, Iran e-mail: ahmadyaminisharif@yahoo.com A. Shafiee : M. Shahrzad Department of Cardiovascular Research, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran J Interv Card Electrophysiol (2013) 38:43–49 DOI 10.1007/s10840-012-9775-1