Catheter Ablation -> Ventricular Arrhythmias -> Mapping & Imaging D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-102 - Activation Pattern And Conduction Velocity Of Voltage Map Channels During Baseline Rhythm In Patients With Structural Heart Disease During Ventricular Tachycardia Ablation (ID 664)

 T. Kitamura: Nothing relevant to disclose.


Background: Voltage map channels can be substrate ablation targets. Activation pattern during baseline rhythm on the voltage map channels of ventricular tachycardia (VT) remains unknown. Moreover, conduction velocity (CV) during baseline rhythm has been reported to be crucial to identify VT substrate.
Objective: To demonstrate activation pattern and CV of VT channel during baseline rhythm in patients with structural heart disease (SHD) who underwent the VT ablation.
Methods: This retrospective observational study included patients with SHD who underwent VT ablation who had voltage and activation maps acquired by using multipolar mapping catheter. We assessed the maps during sinus rhythm or ventricular pacing rhythm. We defined VT channels by (1) relative higher voltage within the scar by using voltage limit adjustment and (2) pace-mapping/activation mapping of clinical/induced VT. Relationship between latest activation area during baseline rhythm and VT channels was also assessed. Moreover, CV during baseline rhythm on the channels were evaluated except for collision area.
Results: We identified 37 VT channels in 30 patients (age: 66, EF: 35%, ischemic: 20). The average voltage threshold to identify the VT channels was 0.73 mV. 78% (29/37) of activation pattern on VT channels showed collision in the channels. 76% (28/37) of VT channels did not include latest activation during baseline rhythm. The median CV of edge of the channels with collision pattern was 0.45 m/s while that with non-collision pattern was 1.1 m/s (P = 0.001).
Conclusion: VT channels without latest activation site and with collision activation during baseline rhythm in VT channel can be substrate ablation targets.