Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Mapping & Imaging D-PO01 - Featured Poster Session (ID 11) Poster

D-PO01-140 - Rapid Confirmation Of Conduction Block Across Linear Ablation Lesions Using Real-time Propagation Vector Mapping In A Novel Expandable Lattice Radiofrequency Electrode Mapping/ablation System (ID 110)

  H. Nakagawa: Honoraria/Speaking/Consulting Fee - Japan Lifeline; Fukuda-Denshi; Boston Scientific. Research (Contracted Grants for PIs and Named Investigators only) - Affera; Biosense Webster, Inc..


Background: An expandable lattice irrigated ablation electrode rapidly creates wide RF lesions (5 sec RF: 12-14mm wide, 4-5 mm deep) with low risk of thrombus and steam pop. This system uses close unipolar electrodes (CUE) for real-time propagation vector (Vct) and activation mapping.
Objective: Test effectiveness of Vct mapping for rapid recognition of conduction block across linear lesions and localization of a gap across the cavo-tricuspid (CTI), mitral isthmus (MI) or roof line (RL).
Methods: 30 pts were enrolled. An 8F mapping/ablation catheter (Sphere 9, Affera, Inc) with an expandable 9 mm lattice tip, magnetic location sensor, 9 mini-surface electrodes and a central reference electrode was used. An anatomical shell of the RA or LA was formed by the outer boundary of the lattice at each position. 9 CUE (between each of the 9 mini-surface electrodes and central non-contact reference electrode) were acquired at each site. Vct was created in real-time using activation times detected on the 3 neighboring CUE with the highest dV/dt (Fig A). Linear ablation (9mm lattice tip electrode for RF: 3-5 sec, current density <10 mA/mm2, electrode temperature <75°C) was performed across the CTI (25 pts), MI (16 pts) or RL (20 pts) followed by repeat Vct.
Results: Complete conduction block was obtained in 25/25 CTI with 2-22 (median 5) RFs, 16/16 MI with 3-16 (median 7) RFs and 19/20 RL with 3-8 (median 5.5) RFs. Vct accurately showed conduction block by reversal of activation (Figs B-D), confirmed by activation mapping (same catheter).
Conclusion: Vct effectively provided local activation direction during mapping and ablation, with rapid recognition of block and localization of any gap in the ablation line.