Identifying a Gap in a Cavotricuspid Isthmus Flutter Line Using the Advisor™ HD Grid High-Density Mapping Catheter

This report discusses the mapping of an incomplete cavotricuspid isthmus flutter line with a high-density mapping catheter to visualize the arrhythmogenic substrate responsible for incomplete block. The relevant signals were unapparent when using a traditional ablation catheter but were evident with application of a high-density mapping catheter. High-density mapping holds promise for recording electrograms in gaps in other ablation lesion sets that may not be able to be easily identified using more traditional equipment alone.