Emergence of Multielectrode Mapping

The technological imperative is changing the field of electrophysiology, and we are currently at a crossroads in complex ablation. The rapid emergence of electroanatomic mapping with multielectrode catheters was spawned out of both intellectual necessity (desire for mechanistic insights into arrhythmias) and clinical necessity (to expedite mapping time). During the 1980s, mapping with single-point catheters and multielectrode catheters was proven to be useful for arrhythmia substrate characterization in the intraoperative setting. In 1999, single-point catheter-based mapping was first validated using the CARTO system by Callans et al in a porcine model of myocardial infarction. This validation was performed with 75 endocardial points, and the electroanatomic map obviated the reliance on fluoroscopic substrate-based ablation within regions of low voltage and quickly became the central platform for scar-based ventricular tachycardia (VT) procedures. Seventeen years later, the validation of an automated mapping system (Rhythmia; Boston Scientific, Natick, MA) with microelectrodes on a miniature basket catheter was demonstrated in a porcine model, with an average of >8000 mapping points. It is a foregone conclusion that as a field, we are already on the road to higher resolution with multielectrode catheters becoming the new mainstay for mapping of complex arrhythmias. Several questions require further examination as the optimal role of multielectrode mapping remains to be fully defined (1) How did we get here? (2) What are the obstacles that lie ahead? (3) Where is our ultimate destination?