Classification of atrial flutter

Classification of atrial flutter

Atrial flutter can be classified into isthmus dependent and non-isthmus dependent. Non isthmus dependent flutters are the scar related flutters and caval mediated flutters. Isthmus dependent flutter can be typical and reverse typical depending on whether the reentry is counterclockwise or clockwise. The direction of the less sharper component of the flutter wave is taken as the direction of the wave. If the waves are are positive in inferior leads, it is clockwise loop and if negative, the re-entry loop is counter-clockwise.

Reference

1. Nabar A. A re-analysis of our current understanding of isthmus-dependent atrial flutter: some gaps, some hypotheses. Indian Pacing Electrophysiol J. 2001 Oct 1;1(1):23-31. PMID: 17006568; PMCID: PMC1569894.