An innovative three-step ablation approach including ethanol infusion of the vein of Marshall improves freedom from arrhythmias in patients with persistent atrial fibrillation (AF) compared to pulmonary vein isolation (PVI) alone, according to late breaking science presented at the annual congress of the European Heart Rhythm Association (EHRA 2023, 16–18 April 2023, Barcelona, Spain)– a branch of the European Society of Cardiology (ESC). Preliminary results at 10 months are presented, with follow-up ongoing until 12 months.
The cornerstone of catheter ablation of AF is complete isolation of the pulmonary veins. However, only 50–60% of patients remain in sinus rhythm at two years. Numerous trials of different ablation strategies have failed to demonstrate superiority over PVI.
The Marshall-Plan ablation strategy consists of PVI, ethanol infusion of the vein of Marshall and a linear ablation set to block the three main anatomical isthmuses to the pulmonary veins (dome, mitral and cavotricuspid isthmus lines). The technique focuses on anatomical targets that have been individually recognised as important for the initiation or maintenance of AF but have not been collectively targeted in a systematic manner. The current investigators previously reported encouraging results using this strategy in non-randomised studies.
The present study compared 12-month arrhythmia-free survival with the Marshall-Plan ablation strategy versus PVI only. This was a prospective, randomised, parallel group trial of superiority. The trial included 120 patients with symptomatic persistent AF for more than one month. The average age of participants was 67 years and 21 (18%) were women.
Participants were randomised to receive the Marshall-Plan or PVI alone. Follow-up occurred at three, six, nine and 12 months during which patients underwent a number of tests including an electrocardiogram (ECG), echocardiography, stress test and 24-hour Holter monitoring. Recurrence of arrhythmias was identified using ECG teletransmission, with findings sent to the hospital once a week plus any time the patient had symptoms. The primary endpoint was recurrence of AF or atrial tachycardia lasting more than 30 seconds at 12 months (including a three-month blanking period) after a single ablation procedure.
The total radiofrequency time was significantly longer in the PVI group (29 minutes) compared with the Marshall-Plan group (23 minutes; p<0.001). The full lesion set was successfully completed in 53 patients (88%) receiving the Marshall-Plan strategy and 59 patients (98%) receiving PVI only. In an intention-to-treat analysis, the recurrence of arrhythmias after an average follow-up of 10 months was significantly higher in the PVI group compared with the Marshall-Plan group (18 versus 8 patients; p=0.026). Follow-up will continue until 12 months.
Principal investigator Nicolas Derval (University Hospital of Bordeaux, Bordeaux, France) said: “After 10 months of follow up, the success rate in the Marshall-Plan group was significantly better (87%) compared to the PVI only group (70%). However, the results are still preliminary as follow-up is not completed for all patients. While the findings indicate that the Marshall-Plan strategy holds promise for patients with persistent AF, they need to be confirmed in a multicentre trial.”
