Does Merged three-dimensional mapping Improve Contact foRce and
long-term procedure Outcome in Atrial Fibrillation ablation? (MICRO-AF
study): A prospective randomized controlled study
Abstract
Introduction: Integration of electroanatomical map (EAM) with
preacquired three-dimensional (3D) cardiac images provides detailed
appreciation of the complex anatomy of the left atrium (LA) and
pulmonary vein (PV). High-density (HD) multi-electrode mapping catheters
have enabled creating more accurate EAM reflecting real-time
volume-rendered LA-PV geometry during atrial fibrillation (AF) ablation.
However, no study has compared the outcomes of AF ablation using HD-EAM
versus 3D-merged map. We aimed to investigate the procedural and
clinical outcomes of AF ablation with HD-EAM (HD-EAM group) versus
3D-merged map (Merge group). Methods: One hundred patients
(59.5±11.5years, 53% with paroxysmal AF [PAF]) were randomly
assigned (1:1) to HD-EAM or Merged group. HD multi-electrode mapping and
contact force (CF)-sensing catheters were used to create virtual LA-PV
chamber and to perform wide antral circumferential ablation (WACA),
respectively. Results: The two groups showed no significant differences
in baseline characteristics and procedural data including ablation time,
fluoroscopy time, LA voltage, and CF. PV isolation with a single WACA
line was achieved in 21 (42%) and 27 (54%) patients in the Merge and
HD-EAM groups, respectively (P=NS). CF was significantly lower in
lesions with gap than lesions without gap after a single WACA (7.3±7.3 g
vs. 16.0±8.3, respectively, P<0.001). During the 12-month
follow-up, no significant difference in AF recurrence was observed
between two groups, irrespective of AF type. In multivariate analysis,
non-PAF was an independent risk factor for AF recurrence. Conclusion:
Integration of 3D cardiac imaging did not improve procedural and
clinical outcomes. HD-EAM provides an accurate real-time LA geometry.