The Fast Zone for Reentry.

Reentry is the most common mechanism for arrhythmia in patients treated in the electrophysiology laboratory. Mapping and defining the exact circuit to then allow targeting an ideal site for ablation is challenging. However, as reentry usually involves a relatively large circuit often coupled with a discrete slow zone of conduction, we are able to use the classical techniques of entrainment mapping to find and ablate the circuit isthmus containing the slow zone ablation for permanent elimination.