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Figure 5. Mechanisms of Atrial Flutter and Atrial Tachycardia
Atrial arrhythmias can be broadly classified as focal, small circuit or macro-reentry. e
most common forms of atrial macro-reentry are variants of classical cavo-tricuspid isthmus
dependent flutter (Figure 5 A-B). Common re-entrant circuits are peri-mitral or "mitral
isthmus-dependent" or alternately "roof-dependent" circuits (Figure 5 E-F), which occur
around either the le or right sided PVs. Ablation of these circuits can be accomplished by
creation of a linear ablation lesion in the form of a mitral or an anterior line for peri-mitral
flutter or a roof line for roof-dependent flutters. Micro-reentrant atrial flutter can be
ablated with a focal lesion (Figure 5D).
Treatment
