Radiofrequency catheter ablation of common-type atrial flutter guided by conventional versus electroanatomical mapping.

Radiofrequency catheter (RF) ablation aiming the complete conduction block of the cavotricuspid isthmus has become treatment of choice for common type atrial flutter. Different approaches to guide the ablation procedure are used. For the conventional approach multipolar catheters in the right atrium and in the coronary sinus are required to detect the induction of conduction block via the isthmus. RF current is applied starting at the ventricular site of the cavotricuspid isthmus under fluoroscopic control to recognise dislocation of the ablation catheter and to avoid potential complications. Three-dimensional electroanatomic (CARTO) activation mapping can be helpful to guide atrial flutter ablation. By the help of a magnetic sensor, embedded in the tip of the mapping catheter, a virtual frame of the cavotricuspid isthmus will be reconstructed. The middle region between the virtual septal and posterolateral border of the cavotricuspid isthmus will be targeted for the ablation lesion line. Both approaches have been shown to be associated with a high acute success rate and a low recurrence rate. The major difference is that the CARTO system leads to a substantial reduction of fluoroscopic time required for atrial flutter ablation. Thus, CARTO-guided ablation directed at the cavotricuspid isthmus represent a modern method for rapid and successful treatment of common-type atrial flutter with low radiation exposure. (Fig. 4, Ref. 16.)