Catheter Ablation of Right Ventricular Endocavitary Arrhythmias

Figures

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  Central Illustration. Catheter Ablation of Right Ventricular Endocavitary Arrhythmias AAD = antiarrhythmic drug; LVEF = left ventricular ejection fraction; NICM = nonischemic cardiomyopathy; RF = radiofrequency; RV = right ventricular; other abbreviations as in Figures 1 and 2.

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  Figure 1. Example Tracings of Moderator Band Arrhythmias in our Study Population (A) Representative 12-lead ECGs of PVCs ablated from the lateral, body, and medial moderator band, (B) a PVC with a short coupling interval degenerating into polymorphic VT which was ablated at the lateral junction of the moderator band complex and (C) sustained symptomatic VT ablated from the body of the moderator band. ECG = electrocardiogram; PVC = premature ventricular contraction; VT = ventricular tachycardia.

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  Figure 2. Site of Ablation on the Moderator Band Complex Data presented as raw counts (n = 47 total observations) and group comparisons were made using Fisher exact test (P = 0.03). VF = ventricular fibrillation; other abbreviations as in Figure 1.

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  Figure 3. Changes in Premature Ventricular Contraction Burden and Left Ventricular Ejection Fraction (A) Premature ventricular contraction (PVC) burden in the 25 patients referred for PVC ablation decreased from 15% (IQR: 9%-22%) prior to the index ablation to 2% (IQR: 1%-3%) at the last clinical follow-up (P < 0.01); data displayed as median (IQR). (B) Left ventricular ejection fraction (LVEF) improved from 38% ± 6% to 55% ± 6% in the 7 patients with PVC-mediated cardiomyopathy after catheter ablation (P < 0.01); data displayed as mean ± SD.

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  Figure 4. Antiarrhythmic Therapy The distribution of antiarrhythmic therapy prior to index ablation and at the last clinical follow-up in patients referred for ablation of PVC-triggered VF (A) and VT (B). Abbreviations as in Figures 1 and 2.

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  Figure 5. Freedom From Right Ventricular Endocavitary Complex Arrhythmias Postablation (A) Cumulative freedom from right ventricular endocavitary complex arrhythmias following index ablation and (B) freedom from arrhythmias stratified by clinical presentation (P = 0.49). Abbreviations as in Figures 1 and 2.

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  Figure 6. Coupling Interval and QRS Duration of Premature Ventricular Contractions (A) Coupling interval and (B) QRS duration of premature ventricular contractions (PVCs) originating from the moderator band stratified by site of ablation. Data presented as median (IQR). Group comparisons were made using the Kruskal-Wallis test. MB = moderator band.

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  Figure 7. Example Case Example case of a 45-year-old gentleman with a history of an out-of-hospital cardiac arrest with documented VF who had recurrent appropriate ICD shocks (A). He had nonobstructive coronary artery disease with a structurally normal heart with focal nonspecific delayed gadolinium enhancement noted at the right ventricular insertion site and a variant of uncertain significance in alpha-protein kinase 3. He underwent ablation for PVC-triggered VF with earliest pre-QRS local ventricular electrogram (69 ms) (B) in the lateral aspect of the moderator band (C). Radiofrequency ablation followed by cryoablation was used with intracardiac echocardiography depicting the site of ablation (D). He was continued on flecainide 100 mg orally twice daily for 3 months postablation without clinical recurrence. ICD = implantable cardioverter-defibrillator; VF = ventricular fibrillation; other abbreviations as in Figures 1 and 6.