Predictors of success in radiofrequency catheter ablation of atrial flutter

Radiofrequency catheter ablation of typical atrial flutter at the isthmus b etween the tricuspid annulus and the inferior vena cava is established. How ever in selected patients, the creation of a continuous linear lesion at th e targeted isthmus requires a lengthened procedure or is not feasible at al l and atrial flutter recurrences are common. In a retrospective analysis, we found that an intraoperatively determined d istance between the tricuspid annulus and the inferior vena cava of >.2.5 c m is an independent predictor of a lengthened or failed ablation procedure. Additional equipment, e.g., long introducer sheaths, adapted ablation cath eter design, or irrigated tip ablation, as well as alternative ablation app roaches, e.g., linear lesions between the tricuspid annulus and Eustachian ridge, have been invented in order to increase the acute success rate or de crease fluoroscopy and procedure time. In a prospective study on the effects of various conduction properties at t he isthmus between tricuspid annulus and inferior vena cava following radio frequency ablation of atrial flutter, we showed previously that others than a complete bidirectional conduction block predicts a high recurrence rate of atrial flutter. For determination of transisthmal conduction properties following ablation, established mapping approaches are documentation of dou ble potentials at the ablation line and right atrial activation sequence fo llowing posteroseptal and low lateral right atrial pacing. Novel threedimen sional mapping systems, i.e., Carto(R) and EnSite(R), may further enhance t he accuracy of conventional mapping techniques.