Potential arrhythmic substrate of atrial fibrillation at the left atrial diverticulum.

Figures

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  Fig. 1. High density left atrial voltage maps Fig. 1A: Preoperative 3D-CT that detects a diverticulum on the posteroseptal wall of the LA. High density left atrial voltage maps created during AF ablation are shown using CARTO (Biosense Webster, Inc, Diamond Bar, CA, USA) recorded by a PentaRay catheter (Biosense Webster, Inc, Diamond Bar, CA, USA). Purple color represents areas greater than the threshold of 0.5 mV. Fig. 1B, 1C:Anterior-posterior (AP) view (B) and posterior-anterior (PA) view (C). They show the voltage map after the first session ablation procedure with isolation of PVI and post wall isolation. PV reconnection was also identified in the left anterior PV and the roof with atrial fibrillation recurrence after undergoing the pulmonary vein isolation (PVI) procedure. Figure 1B illustrates representative electrograms and cycle lengths (CL) for left atrial diverticulum (LAD) and the surrounding area. AFCL: atrial fibrillation cycle length

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  Fig. 2. CARTOFINDER (Biosense Webster, Inc, Diamond Bar, CA, USA) module maps and electrograms Fig. 2A, 2B: Anterior-posterior (AP) view (A) and posterior-anterior (PA) view (B). They show the CARTOFINDER module map around the diverticulum after pulmonary vein isolation and box isolation. Drivers with a focal repetitive activation pattern (labeled in green) were identified at the posteroinferior and posterolateral sites (B). Fig. 2C: Posterior-anterior (PA) view after ablation. Red tags represent ablation lesions. Fig. 2D: The unipolar electrogram on the PentaRay catheter (Biosense Webster, Inc, Diamond Bar, CA, USA). This figure illustrates the unipolar electrogram on the PentaRay catheter (Biosense Webster, Inc, Diamond Bar, CA, USA) recorded posteroinferior and posterolateral sites showing a QS pattern (20A1, 2, 13, 14, and17) (cycle length 146 ms).

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  Fig. 3. The distribution of CFAE potential (CFAE map), the degree of fragmented potentials (CFAE potential) by module of CARTO system, and electrogram under ablation of AF Fig. 3A: Complex fractionated atrial electrograms (CFAE) map by interval confidence level (ICL) mode of the CARTO system during AF before CFAE ablation (anterior-posterior [AP] view) and representative electrograms for LAD and the surrounding area. The areas with the highest number of ICLs are shown in red, while those with a low number of ICLs are displayed in purple. The color bar is configured to display 60% of the maximum ICL value. Fig. 3B: CFAE map after atrial fibrillation (AF) termination. Red tags represent the ablation lesions for CFAE. Fig. 3C: Intracardiac electrograms. These electrograms are shown to be wider and have more fragmented deflections in the left atrial diverticulum (LAD) than in the right atrium (RA) and coronary sinus (CS). Atrial fibrillation terminated into sinus rhythm during ablation encircling a diverticulum source at the posteroseptal left atrium. SVC dis: distal superior vena cava SVC pro: proximal superior vena cava RA dis: distal right atrium RA pro: proximal right atrium CS dis:…