Preventive Linear Ablation Strategy for Intra‐Atrial Reentrant Tachycardia Following Cardiac Surgery

Figures

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  FIGURE 1. Simplified schematic of the potential reentrant site and preventive ablation strategy. The left panel illustrates potential sites of intra‐atrial reentrant tachycardia following cardia surgery. The right panel depicts the corresponding preventive ablation lines based on these arrhythmogenic substrates. Gray indicates low‐voltage region. Red point indicates ablation mark.

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  FIGURE 2. Example of preventive ablation guided by voltage mapping. Preventive linear ablation in right atrium. This patient, who underwent mitral valve (MV) replacement alone, presented double potential line and low‐voltage area in the free wall and a low‐voltage zone in the septum (A, B). Following successful termination of typical atrial flutter with CTI ablation, preventive ablation lesions were delivered between the septal incision and the superior vena cava (C, D). Linear ablation between incision of the free wall and the inferior vena cava was not performed due to the presence of complete conduction block, as evidenced by the double potentials shown in the small dark panel (A). Preventive linear ablation in left atrium (lower panels). The patient, who had previously undergone MV replacement and Maze procedure, exhibited low‐voltage zones on both the anterior and posterior left atrial walls (E, F). Box isolation was performed on the posterior wall, and an anterior line ablation was created connecting the MV to the left superior pulmonary vein (G, H). Pulmonary vein isolation was performed again due to pulmonary vein conduction reconnection of pulmonary veins.

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  FIGURE 3. Kaplan–Meier Curves of Freedom from ATA recurrence. Comparison of freedom from atrial arrhythmia recurrence between Control Group and Study Group. Follow‐up times are expressed in months following the end of the procedure. A statistically significant difference was observed in atrial arrhythmia recurrence rates between the groups.

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  FIGURE 4. Example of SVC‐related flutter recurrence after CTI‐dependent flutter ablation. (A) The activation mapping demonstrated that a macro‐reentry involving the SVC in a patient with atrial septal repair (solid yellow circle; wavy line indicates the slow conduction area) (Video S2 in the Data Supplement). The small box highlights a long‐duration low‐voltage area at critical isthmus located at the junction between the SVC and right atrium. (B–D) Voltage maps revealed a large low‐voltage area along the right free wall, septal surface and CTI region. (E, F) Ablation at the critical isthmus terminated flutter (red points indicates ablation sites). CTI, cavotricuspid isthmus; SVC, superior vena cava.