Novel mapping algorithm during catheter ablation for ventricular parasystole originating from left anterior fascicle

Figures

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  FIGURE 1. A 12‐lead electrocardiogram demonstrating parasystole. A 17‐year‐old woman presented with dyspnea and palpitations. A 12‐lead electrocardiogram was performed and displayed parasystole (red arrow head) with a relatively narrow QRS duration (112ms), right bundle branch block type, and inferior axis morphology. QRS complexes of parasystole showed varying coupling but the same interectopic intervals (1290 ms)

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  FIGURE 2. Activation maps during parasystole and sinus rhythm with intracardiac electrograms. Parasystole in a 17‐year‐old woman experiencing dyspnea and palpitations was mapped using the CARTO 3 system version 7 (Biosense Webster, Diamond Bar, CA), and the filter Carto Confidense Module with Pattern Matching. We acquired the QRS morphology of sinus and parasystole beats and utilized a correlation threshold of ≧0.97. Any other functions for distinguishing the parasystole from sinus beat (ie, Cycle length, Tissue Proximity Indication) were not used. A, The activation map of conduction system of left ventricle (LV) during sinus rhythm in the anterior posterior (AP) view is shown. This map clearly demonstrates the conduction system, including the left side His bundle (Left HB), the left anterior fascicle (LAF), and the left posterior fascicle (LPF). The distance from the left side his and the targeted proximal LAF was 11.5 mm. B, The activation map during the parasystole of LV in the AP view is shown. The earliest site was close to the proximal end of the left anterior fascicle area. C, The intracardiac electrogram of this location demonstrated a pre‐QRS potential preceding the QRS complex…