Physiology-Guided Selective Posteromedial Left Ganglionated Plexus Cardioneuroablation for Functional Paroxysmal Atrioventricular Block

Figures

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  Visual Summary. Physiology-Guided Cardioneuroablation for Functional Atrioventricular Block Preprocedural ECG strip showing marked bradycardia with multiple nonconducted P waves, consistent with high-grade AV block. Surface ECG and intracardiac recordings during bilateral ECVS before ablation showing reproducible high-grade AV block during right-sided (left panel) and left-sided (right panel) stimulation. Three-dimensional electroanatomical map of the left atrium showing regions with fractionated atrial electrograms, predominantly localized to the ganglionated plexus regions. Electroanatomical map illustrating the final PMLGP ablation lesion set (green tags). Repeat ECVS after ablation demonstrates abolition of previously inducible AV block, with only mild heart rate slowing. AV = atrioventricular; ECG = electrocardiogram; ECVS = extracardiac vagal stimulation; PMLGP = posteromedial left ganglionated plexus.

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  Figure 1. Preprocedural Holter Rhythm Strip The tracing shows marked bradycardia with a heart rate of approximately 12 beats/min, an R-R interval of about 5 seconds, and 4 nonconducted P waves, consistent with high-grade atrioventricular block.

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  Figure 2. Fluoroscopic Anteroposterior Views of Catheter Positioning for ECVS Fluoroscopic anteroposterior views demonstrating quadripolar catheter positioning during (A) right-sided and (B) left-sided extracardiac vagal stimulation (ECVS).

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  Figure 3. Bilateral ECVS-Induced Atrioventricular Block Before Ablation Surface electrocardiographic and intracardiac tracings during baseline (A) right-sided and (B) left-sided extracardiac vagal stimulation (ECVS) before ablation. Red brackets indicate the onset, duration, and termination of high-grade atrioventricular block induced during approximately 5-second stimulation on both sides.

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  Figure 4. Biatrial Voltage Maps Using High-Density Mapping Right and left atrial voltage electroanatomical maps acquired using the HD Advisor mapping catheter on the EnSite X system, displayed on the left anterior oblique caudal view. CS = coronary sinus; IVC = inferior vena cava; LAA = left atrial appendage; LIPV = left inferior pulmonary vein; LSPV = left superior pulmonary vein; MA = mitral annulus; RSPV = right superior pulmonary vein; SVC = superior vena cava; TA = tricuspid annulus.

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  Figure 5. Automated Fractionation Map Demonstrating Fractionated Atrial Electrograms in the RSGP, LSGP, and PMLGP Regions Regions demonstrating fractionated atrial electrograms with ≥2 detected deflections are identified on automated fractionation mapping, with visible fractionated areas in the RSGP, LSGP, and PMLGP regions. The 1 to 15 color scale on the left represents the automated fractionation score generated by the mapping system; higher values indicate progressively greater electrogram complexity and a larger number of detected deflections. In the right column, a representative fractionated electrogram recorded from the PMLGP region is shown, with an inset panel (Top) displaying a magnified segment of the electrogram for clearer visualization of the individual deflections. LSGP = left superior ganglionated plexus; PMLGP = posteromedial left ganglionated plexus; RSGP = right superior ganglionated plexus.

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  Figure 6. ECVS Showing Partial Vagal Modification After Initial PMLGP Ablation Surface electrocardiographic and intracardiac tracings during repeat prolonged ECVS after ablation demonstrate (A) mild heart rate slowing without atrioventricular block on right-sided stimulation, while (B) left-sided stimulation induces a less pronounced yet still persistent atrioventricular block (red bracket) compared with baseline (see Figure 3B), consistent with partial and selective vagal modification. ECVS = extracardiac vagal stimulation; PMLGP = posteromedial left ganglionated plexus.

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  Figure 7. Final PMLGP Lesion Set With Resolution of ECVS-Induced Atrioventricular Block (A) Three-dimensional electroanatomical mapping image illustrating the final lesion set in the PMLGP region, with green tags indicating ablation points, each achieving a lesion size index of ≥6. (B) After completion of the final lesion set, repeat left-sided ECVS demonstrates abolition of the previously observed atrioventricular block after the initial ablations, with only mild heart rate slowing. ECVS = extracardiac vagal stimulation; PMLGP = posteromedial left ganglionated plexus.