Ablation of Postsurgical Atrial Flutter Guided by Concealed Fragmented Potentials

Postsurgical atrial flutter constitutes a significant portion of atypical atrial flutter. Its activation sequence is complex and exhibits significant individual variation.

A 76-year-old woman with a history of atrial septal defect repair was admitted for atrial flutter. Although initial mapping suggested a focal atrial tachycardia originating from the left anterior wall, complex signal identification revealed previously overlooked prolonged low-amplitude fragmented potentials within the map. This unveiled a macro-re-entrant circuit around the right superior pulmonary vein. After radiofrequency ablation at the critical fragmented potential site, sinus rhythm was restored.

In this case, the final mapping diagnosis markedly differed from the initial interpretation, highlighting the critical importance of precisely identifying the key slow conduction zone.

Tachycardias after cardiac surgery are predominantly atypical atrial flutter. Detailed mapping and meticulous analysis are paramount for successful ablation of complex tachycardias.