DIRECT ANGIOGRAPHY OF THE CORONARY SINUS - IMPACT ON LEFT POSTEROSEPTAL ACCESSORY PATHWAY ABLATION

The purpose of this study was to determine the incidence and types of venous branches and anomalies in posteroseptal accessory pathways (APs ) and whether these findings are indicative for successful ablation si tes. Some posteroseptal APs may be located epicardially, or may be ass ociated with venous anomalies or related to the middle cardiac vein. T hese APs account for many of the failures encountered during endocardi al ablation. Direct coronary sinus (CS) angiography was performed in 4 3 consecutive patients with left posteroseptal APs (n = 23) and in 20 patients with AV nodal reentrant tachycardia prior to catheter ablatio n. In 14 (61%) of 23 APs, a venous branch or an anomaly of the CS was found in the posteroseptal region (6 with middle cardiac vein, 2 with other ventricular venous branches, and 6 had a diverticulum). Eleven ( 48%) of 23 APs were successfully abolished from within that demonstrat ed venous system, with a median of four radiofrequency impulses. In th e remaining 12 (52%) patients, ablation was attempted from the endocar dial site of the mitral annulus. Repeat angiography after energy deliv ery revealed no major complications in any patient. One (5%) patient w ith AV nodal reentrant tachycardia had evidence of a CS anomaly (P < 0 .01). Various types of venous branches and anomalies. are associated w ith the majority of patients with left posteroseptal APs. The APs are directly related to these complex findings, and AP conduction can easi ly be eliminated from within the venous branches. CS angiography is su ggested prior to catheter ablation of left posteroseptal APs to facili tate the ablation procedure.