Po-05-092 bipolar electrogram peak frequency value derived from high-density electroanatomic mapping efficiently identifies the critical isthmus in scar-related ventricular tachycardia

It is of challenges to differentiate local activities from far-field potentials, especially the multicomponent electrograms of diastolic potentials in scar-related reentrant ventricular tachycardia (VT). The peak frequency (PF) of each electrogram has the potential to discriminate near-field from far-field potentials. The study aimed to identify the VT isthmus by applying PF criteria on VT activation maps. The study consisted of 10 patients with scar-related VT (ischemic/nonischemic cardiomyopathy 6/4). The characteristics of the VT circuits were assessed using high-density multielectrode catheters. VT isthmuses were identified based on activation maps, entrainment, and ablation results. The accuracy of applying PF value over the activation map in detecting VT isthmus was assessed. 12 VT isthmuses were identified. The mean bipolar voltage and PF of the VT isthmuses were 0.26 ± 0.13 mV and 319.3 ± 58.6 Hz respectively. All isthmuses were within areas of bipolar voltage less than 0.5 mV and PF of more than 250 Hz. With the automated -dv/dtmax annotation during VT, the isthmus could be identified in 5 of 12 (41.7%) VT circuits without manual annotation. By automated PF annotation, the VT isthmus could be identified in 9 of 12 (75.0%) VT circuits without the need for manual adjustment. VT isthmus was always located in the electrogram with bipolar LVZ (<0.5 mV) with a PF value over 250Hz during VT. Moreover, the VT isthmus could be more intuitively identified by the automated peak frequency annotation than -dv/dtmax annotation in the current daily practice using high-density 3D electroanatomic mapping system.