MARSHALL bundles elimination, Pulmonary veins isolation and Lines completion for ANatomical ablation of persistent atrial fibrillation: MARSHALL‐PLAN case series

Abstract

Introduction: Beyond pulmonary veins (PV) isolation, the ablation strategy for persistent atrial fibrillation (AF) remains controversial. Substrate ablation may provide a high termination rate but at the cost of impaired atrial physiology and recurrent complex re-entries. To overcome these pitfalls, we investigated a new lesion set based on important anatomical considerations. Methods and Results: The case series included 10 consecutive patients with persistent AF. Three atrial structures were successively targeted: (1) coronary sinus and vein of Marshall (CS-VOM) musculature elimination; (2) PVs isolation; and (3) anatomical isthmuses block. The lesion set completion was the procedural endpoint. Step 1: VOM ethanol infusion was feasible in all cases (mean time of 33.4 ± 9.4 minutes), mean radiofrequency (RF) time for CS-VOMbundles was 14.4 ± 6.9 minutes. Step 2: mean RF time for PV isolation was 27.7 ± 9.3 minutes. Step 3: mean RF time for mitral, roof, and cavotricuspid lines was 5.7 ± 2.3, 8.1 ± 4.3, and 5.9 ± 1.9 minutes, respectively. The lesion set was achieved in all patients. Mean procedure time was 270 ± 29.9 minutes. AF termination and noninducibility were, respectively, obtained in 50% and 90% of the patients. After a 6-month follow-up, all patients were free from arrhythmia recurrence. Conclusion:The present case series reports a new ablation strategy systematically targeting anatomical structures previously identified as possibly involved in the fibrillatory process and the recurrent tachycardias. The resulting lesion set provides good short-term outcomes. Although promising, these preliminary results need to be confirmed in the larger prospective study.

Computed tomography‐derived left atrial volume index, sex, and age to predict the presence and the extent of left atrial low‐voltage zones in patients with atrial fibrillation: The ZAQ score

“…Surgical ablation studies support the hypothesis that empiric linear ablation is able to improve success rates especially in persistent AF 4,5 . Substrate modification using catheter techniques has received renewed interest, and additional targeted ablation of low‐voltage zones (LVZs) has yielded favorable results 6,7 …”

“…4,5 Substrate modification using catheter techniques has received renewed interest, and additional targeted ablation of low-voltage zones (LVZs) has yielded favorable results. 6,7 Late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (MRI) 8,9 and electroanatomic voltage map (EAVM) 10 have been used for substrate characterization. The former is difficult to quantify using standard MRI software.…”

Beyond pulmonary veins… The new horizon remains atrial anatomy

“…Altogether, the PVs bundles, the distal CS bundles, the VOM bundles, the three anatomical isthmuses (mitral, roof, and cavotricuspid) as well as the Bachmann bundle, the fossa ovalis and the proximal CS bundles are key muscular components of the native atrial network which constitute the critical paths for pathological re‐entry or physiological conduction. A sensible anatomical ablation for persistent AF ablation will target the first and respect the others (Figure ) . This approach is not drawn from a blank canvas: surgeons already outlined a very solid strategy with the Cox‐maze .…”

Double trouble within the coronary sinus: What is the mechanism?

“…Despite all these robust publications, during several years the clinical implications of these connections have been relatively neglected by the electrophysiological community. However, besides their importance in the understanding of LATs as highlighted by our observation, a recent publication has pointed out the interest of these CS‐LA connections (in particular the Marshall's bundle) as potential targets for the treatment of persistent AF in humans …”

“…However, besides their importance in the understanding of LATs as highlighted by our observation, a recent publication has pointed out the interest of these CS-LA connections (in particular the Marshall's bundle) as potential targets for the treatment of persistent AF in humans. 5…”