Effects of High-Energy Electrical Shocks Delivered to the Atrium of the Coronary Sinus

Catheter mediated electrical ablation of posterior septal accessory pathways is appealing not only because of the opportunity to avoid a sternotomy but also because posterior septal accessory pathways are recognized as the most difficult type of accessory pathway to ablate surgically [1]. Previous work has documented that catheter mediated electrical ablation of posterior septal accessory pathways is, indeed, clinically feasible although with variable success [2–8]. The purpose of this chapter is to review our work investigating the histologic effects of single, damped sine wave defibrillator pulses on the canine proximal coronary sinus (CS) in order to gain insight into the factors leading to success or failure of the technique for posterior septal accessory pathway ablation in man [9–12].