Dual-Modality Focal Ablation for Refractory Ventricular Summit Ectopy

Figures

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  Figure 1. Baseline Electrocardiogram Demonstrate the Clinical Premature Ventricular Contraction Morphology (A) Sinus rhythm with the clinical premature ventricular contraction in bigeminy fashion. (B) Maximum deflection index calculation which was suggestive of intramyocardial/epicardial exit. (A) Maximum peak deflection measurement. (B) QRS width. A/B = maximum deflection index.

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  Figure 2. Site of Earliest Activation for the Premature Ventricular Contraction (A and B) Location of the earliest signal on right anterior oblique (RAO) and left anterior oblique (LAO) fluoroscopy. (C) Local electrogram at the site of the earliest activation. Note that the unipolar signal has an rS configuration, which was suggestive of deeper foci. Please see Figure 3 for signal with Map-iT catheter and sites of ablation.

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  Figure 3. Sites of Ablation (A) Left anterior oblique cranial. (B) Left lateral. The CS, GCV, AIV, RVOT, LVOT, and AV/aorta are shown. Blue, orange, and white dots: lesions from pulsed field ablation, with colors varying based on contact force algorithms. Red dots: radiofrequency ablation lesions. The green electrode and circle highlight the earliest signal on the Map-iT catheter. (C) Local electrogram from the Map-iT catheter. AIV = anterior interventricular vein; AV = aortic valve; CS = coronary sinus; GCV = great cardiac vein; LVOT = left ventricular outflow tract; RVOT = right ventricular outflow tract.

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  Figure 4. Signal From the Endocardial Left Ventricular Outflow Tract Site Where Durable Suppression Was Achieved As illustrated, the bipolar signal was marginally ahead of the QRS, with an rS on the unipolar electrogram (ABL uni d), suggesting a deeper focus.

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  Figure 5. 2-Chamber Myocardial Delayed Enhancement Sequence Demonstrated New Changes Corresponding to the Targeted Areas Consistent With Ablation (Encircled Area)