3-D propagation map of atrial flutter in the human right atrium, obtained with NAVAX.  Cardiac activation sequence is color coded, white color represents earliest activation or location of arrhythmia , if arrhythmia is focal ( localized to very small area ). Since atrial flutter is large ( macro re-entrant ) electrical circuit-white color shows depolarized ( activated ) cardiac tissue,  Tricuspid valve and very thick muscular ridge in the right atrium ( crista terminalis ) acts like a barriers to electrical conduction,  predetermining direction of the circuit.

Ablation of atrial flutter. 3-D mapping with NAVAX demonstrates conduction block between inferior vena cava and tricuspid valve after ablation. Ablation lesions marked with white circles.  Propagation of electrical depolarization stops at the ablation line. Flutter ablation is effective in about 90-95% of patients, who have typical flutter circuit.  In about 5% of patients some tissue in ablation line  may recover and result in small gaps and recurrence of flutter. This may require to place additional lesions to " seal " gaps in the line.