Outcomes of repeat catheter ablation using magnetic navigation or conventional ablation

After initial catheter ablation, repeat procedures could be necessary. This study evaluates the efficacy of the magnetic navigation system (MNS) in repeat catheter ablation as compared with manual conventional techniques (MANs). The results of 163 repeat ablation procedures were analysed. Ablations were performed either using MNS (n 84) or conventional manual ablation (n 79). Procedures were divided into four groups based on the technique used during the initial and repeat ablation procedure: MANMAN (n 66), MANMNS (n 31), MNSMNS (n 53), and MNSMAN (n 13). Three subgroups were analysed: supraventricular tachycardias (SVTs, n 68), atrial fibrillation (AF, n 67), and ventricular tachycardias (VT, n 28). Recurrences were assessed during 19 11 months follow-up. Overall, repeat procedures using MNS were successful in 89.0 as compared with 96.2 in the MAN group (P ns). The overall recurrence rate was significantly lower using MNS (25.0 vs. 41.4, P 0.045). Acute success and recurrence rates for the MANMAN, MANMNS, MNSMNS, and MNSMAN groups were comparable. For the SVT subgroup a higher acute success rate was achieved using MAN (87.9 vs. 100.0, P 0.049). The use of MNS for SVT is associated with longer procedure times (205 82 vs. 172 69 min, P 0.040). For AF procedure and fluoroscopy times were longer (257 72 vs. 185 64, P 0.001; 59.5 19.3 vs. 41.1 18.3 min, P 0.001). Less fluoroscopy was used for MNS-guided VT procedures (22.8 14.7 vs. 41.2 10.9, P 0.011). Our data suggest that overall MNS is comparable with MAN in acute success after repeat catheter ablation. However, MNS is related to fewer recurrences as compared with MAN