Entrainment mapping: Theoretical considerations and practical implementation.

Entrainment mapping enables the diagnosis and characterization of reentrant arrhythmias from analysis of the specific interaction between pacing maneuvers and tachycardia. Described 40 years ago, the implementation and interpretation of pacing maneuvers to entrain tachycardias has evolved into an indispensible tool for diagnosis and mapping reentrant cardiac arrhythmias. For complex re-entry pathways entrainment mapping allows determination of the relation of pacing sites to the re-entry circuit and discrimination of relevant re-entry parts from bystander areas. Careful interpretation is needed to recognize misleading findings. The general physiology of re-entry, and the application, interpretation, limitations, and pitfalls of entrainment maneuvers used for cardiac mapping is reviewed.