PMC9856327_01
(A and B) Pre-procedural cardiac computed tomography demonstrating right inferior pulmonary vein, left inferior pulmonary vein, and left superior pulmonary vein have one common trunk. (C) Left atrium voltage map before ablation obtained during pacing from the right atrium shows that the common pulmonary veins were low voltage area bounded by the common trunk entrance.
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It revealed a common trunk from which the bilateral inferior PVs and a left superior PV originated (Figure 1A and B). The three PVs stemming from a common trunk showed a low-voltage area bounded by the common trunk entrance (Figure 1C), which was not captured by electrical stimulation.
(A) Atrial fibrillation occurring upon ectopic firing from right superior pulmonary vein. (B and C) Left atrium voltage map post-ablation in the first session. An isolation line was created to connect the right superior pulmonary vein and the common trunk. The common trunk and four pulmonary veins show low voltage areas. AP, anteroposterior; CS, coronary sinus; PA, posteroanterior; RA, right atrium.
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As AF was noted to occur due to firing from the right superior PV (RSPV) (Figure 2A), we created an isolation line to connect the RSPV and the common trunk (Figure 2B and C) with point-by-point RF applications at 40 W using the contact force-sensing irrigated ablation catheter (ThermoCool SmartTouch SF, Biosense Webster).
(A) The left atrium voltage map before ablation in the second session. Residual irregular potential remains at the border between the common trunk and left atrium. (B) The left atrium voltage map post-ablation. Substrate modification was accomplished by creating a bottom line. PA, posteroanterior.
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AF recurred, and a second catheter ablation session was performed. Although no LA-PV re-conduction was detected, the voltage map showed residual irregular potentials at the boundary between the common trunk and the LA (Figure 3A). Posterior wall isolation (Figure 3B) was conducted using a pentaray catheter after high-dose isoproterenol provocation and confirmed through voltage mapping and pacing with an exit block.