Long-term clinical efficacy of Marshall vein ethanol infusion combined with catheter ablation for persistent AF

Figure 1. Flow diagram of patient enrollment and procedure.

Figure 2. Steps of alcohol ablation of the vein of Marshall (VOM) under x-ray and venography (A) venography visualizing the VOM (white arrow). (B) Intrusion of a guidewire within the VOM (white arrow). (C) Inflation of the OTW balloon in the VOM to 6–8 atm, followed by guidewire removal. (D) Injection of contrast agent through the OTW balloon to visualize the distal VOM (white arrow). (E) Injection of contrast agent through the OTW balloon to visualize the proximal VOM (white arrow). (F) Contrast retention in the VOM region after ethanol injection (white arrow).

Figure 3. Procedure of the updated 2C3L ablation approach. (a) LA voltage mapping before EI-VOM during AF; (b) The upper panel shows the position and course of the Marshall vein (top panel, white arrow), and the lower panel shows contrast staining upon reinjection of the contrast agent through the OTW balloon after ethanol infusion (surrounded by a white dashed line); (c) After EI-VOM, voltage mapping revealed low-voltage areas in the mid-to-distal MI and the anterior and inferior margins of the left pulmonary veins, indicative of tissue injury from chemical ablation; (d) Subsequent bilateral pulmonary vein isolation and linear ablation were performed; within the chemically induced low-voltage zones, ablation power was reduced or omitted in regions with diminished local potentials; (e) After EI-VOM, repeat voltage mapping during sinus rhythm confirmed complete isolation of both pulmonary veins. Additionally, contiguous low-voltage areas (<0.1 mV) were observed at the left atrial roof and MI.

Figure 4. Procedure details of the ablation approach using RFCA alone. (A) LA voltage mapping before ablation during AF; (B) Schematic diagram of the x-ray combined with ICE-guided atrial septal puncture process; (C) Lesion sets of ablation LA voltage; (D) LA voltage under sinus rhythm after bilateral pulmonary vein isolation and linear ablation.

Figure 5. Sinus rhythm maintenance rate survival curve between the EI-VOM + RFCA and RFCA groups after catheter ablation.