Electroanatomic mapping of the right coronary artery: a novel approach to ablation of right free-wall accessory pathways.

BACKGROUND: Catheter ablation of right free-wall (RFW) accessory pathways continues to be associated with lower success and higher recurrence rates compared with other pathway locations. Reliably identifying the precise location of RFW accessory pathways often contributes to the difficulty in ablating these pathways. Improved localization of RFW accessory pathways has been described utilizing multielectrode right coronary artery (RCA) catheterization. This approach has not been widely adopted, in part due to concerns of prolonged catheter placement within the RCA. We describe the technique of creating a 3-D electroanatomic map of the right atrioventricular groove, limiting the duration of a microcatheter within the RCA, to facilitate ablation of RFW accessory pathways. METHODS AND
RESULTS: Following intracardiac identification of a RFW accessory pathway, an octapolar microcatheter was placed in the RCA. A 3-D electroanatomic map of the RCA was created during retrograde accessory pathway conduction using ventricular pacing. Immediately following creation of the map, the RCA catheter was removed. Endocardial mapping and ablation of the RFW accessory pathway was performed using the RCA electroanatomic map as a guide. This technique was used in four pediatric patients. The microcatheter was within the RCA for less than 1 min in all patients. Radiofrequency catheter ablation of the RFW accessory pathways were successfully performed with two lesions. There were no complications or recurrences at follow-up.
CONCLUSIONS: The creation of a 3-D electroanantomic map of the RCA effectively localizes RFW accessory pathways and facilitates successful ablation. This technique minimizes the duration of RCA instrumentation.