Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Mapping & Imaging D-PO04 - Poster Session IV (ID 15) Poster

D-PO04-175 - The Utility Of Activation Mapping Integrating Vector And Velocity Information In The Assessment Of Complex Scar Dependent Atrial Tachycardias (ID 1221)


Background: Activation mapping of scar related atrial tachycardias (AT) represents a clinical challenge due to inaccurate annotation of electrograms, annotation of passive diastolic potentials, often not accounting for global activation.
Objective: To assess a novel mapping algorithm (Coherent mapping, Biosense Webster) in complex scar-related ATs in patients with prior atrial fibrillation (AF) ablation. This algorithm follows an integrative approach for annotation of multicomponent electrograms and integrates vector mapping into propagation, without preset mapping windows.
Methods: All patients undergoing mapping and ablation for ATs (focal or reentrant) (2015-2018) were screened for the current study. Maps with >300 activation points per chamber (filling threshold ≤15 mm) were included. Both standard and coherent maps were reviewed by blinded electrophysiologists to assess mechanisms and confidence level with diagnoses (scale 1-10).
Results: A total of 90 AT activation maps were analyzed (83.3% left atrium, median cycle length 275 ms, median 1590 points per map [IQR: 997-2617]). Clinical diagnoses (as confirmed restrospectively with mapping at time of procedures, entrainment, and sites of successful ablation) were confirmed for 75 ATs (43 macroreentry, 20 localized reentry, 12 focal). Using activation maps alone allowed to accurately make the clinical diagnosis in 44.5% of cases with standard mapping vs. 59.5% with coherent mapping. Coherent mapping performed better in reclassification across mechanisms subgroups. Of note, 3 of 4 cases with dual loop reentrant ATs were accurately identified by coherent mapping (vs none with standard). In blinded reviews, concordance in proposed mechanisms between standard and coherent maps was seen in 53.3% of cases, whereas discordance was observed in 44.4% (remaining 2.3% uninterpretable). Electrophysiologists level of confidence with diagnosis was higher using coherent vs standard maps (median 8 vs 6, p<0.001).
Conclusion: In patients with complex scar-mediated ATs, coherent mapping allowed more accurate and confident adjudication of arrhythmia mechanisms compared to standard activation mapping. This algorithm has potential to improve clinical outcomes.