Carto System Reduced Chronic Recurrence Rate of Typical AFL Ablations

Abstract

The recurrence rate after ablation of typical atrial flutter (AFL) is still higher than that of other supraventricular tachyarrhythmias. The purpose of the present study was to determine whether performing ablation using electro-anatomical mapping (CARTO) as guide is able to reduce the incidence of AFL recurrences during the follow-up. Our study population comprises two groups of patients with AFL who underwent linear ablation of cavo-tricuspidal isthmus: 1) from 1996 to 2002, the bidirectional block at level of isthmus was confirmed by conventional method such as changes of propagation sequence on the Halo catheter and/or occurrence of double potential on ablation line (Conv group); 2) from 2002 to 2005, the bidirectional block was confirmed by CARTO system (CARTO group). We enrolled 150 consecutive patients (age 63.0±11.9 yrs). The follow-up period averaged 921 days. The recurrence rate of AFL of Conv group was 12.4% (n=14/113) during 1189 days, while the recurrence rate of CARTO group was 8.1% (n=3/37) during 140 days. In patients who experienced recurrences, the isthmus length was longer than in patients who did not (30 vs 24 mm). The recurrence rate of AFL during the follow-up seems to be lower in patients in whom ablation was performed by means of CARTO system. An isthmus length greater than 30 mm is predictor of AFL recurrence.