Value of high-density mapping in the electrophysiology laboratory

Purpose of review This article uses three commonly encountered clinical scenarios to highlight the value of high-density mapping in the electrophysiology laboratory for the identification of the circuits and substrates during catheter ablation of complex arrhythmias. Recent findings High-density mapping gathered with a multielectrode catheter, with its smaller individual electrode size and closer interelectrode spacing, helps during ablation procedures in a number of ways. When high-density mapping is performed during tachycardia, the characterization of macro-reentrant circuits is better. When there is suspicion of a change in tachycardia during mapping or ablation, the threshold of remapping is significantly lower because of the speed of remapping. When mapping is done during sinus rhythm (substrate mapping), the identification of true scar is more accurate. Lastly, when extensive ablation of a critical isthmus fails to terminate a tachycardia, high-density mapping may reveal the gap(s) along the ablation line and may provide an alternative approach for ablation. Summary High-density mapping shows promises of improving procedural outcomes with shorter procedural times.