Effect of radiofrequency and ethanol ablation on epicardial conduction through the vein of Marshall: How to detect and manage epicardial connection across the mitral isthmus.
Ablation
Ethanol
Marshall bundle
Mitral isthmus
Vein of Marshall
Journal
Heart rhythm
ISSN: 1556-3871
Titre abrégé: Heart Rhythm
Pays: United States
ID NLM: 101200317
Informations de publication
Date de publication:
08 2022
08 2022
Historique:
received:
03
02
2022
revised:
16
03
2022
accepted:
26
03
2022
pubmed:
4
4
2022
medline:
27
7
2022
entrez:
3
4
2022
Statut:
ppublish
Résumé
The vein of Marshall (VOM), which is surrounded by the Marshall bundle (MB), behaves as an epicardial connection bypassing the mitral isthmus. The influence of radiofrequency ablation and VOM ethanol infusion (VOM-EI) on epicardial MB conduction remains unclear. The purpose of this study was to evaluate MB conduction status during mitral isthmus ablation. Of 57 consecutive patients undergoing mitral isthmus ablation, 50 with electrode catheter cannulation into the VOM were analyzed. MB conduction was investigated by evaluating electrograms inside the VOM. Endocardial ablation was initially performed, followed by ablation inside the coronary sinus (CS), if required. Selective VOM-EI was performed if the MB potentials still exhibited early activation after radiofrequency ablation, suggesting the presence of MB connection bridging the mitral isthmus. VOM electrograms composed of near-field MB and far-field left atrial potentials were recorded in all patients. Solely with endocardial ablation, 33 patients (66%) achieved entire mitral isthmus block, and 43 patients (86%) achieved an epicardial MB conduction block. MB potentials exhibited early activation in the remaining 7 (14%), even after requiring CS ablation. VOM-EI then was performed. Elimination of MB potentials was verified by electrode catheter reinsertion after VOM-EI. Mitral isthmus conduction was successfully blocked during VOM-EI in 4 patients and during additional radiofrequency ablation in the remaining 3. All patients finally achieved entire mitral isthmus block. MB is effectively ablated by radiofrequency ablation. Continuous evaluation of MB conduction can reveal epicardial conduction and ablation effect. A residual MB epicardial connection is relatively rare but can be ablated by VOM-EI.
Sections du résumé
BACKGROUND
The vein of Marshall (VOM), which is surrounded by the Marshall bundle (MB), behaves as an epicardial connection bypassing the mitral isthmus. The influence of radiofrequency ablation and VOM ethanol infusion (VOM-EI) on epicardial MB conduction remains unclear.
OBJECTIVE
The purpose of this study was to evaluate MB conduction status during mitral isthmus ablation.
METHODS
Of 57 consecutive patients undergoing mitral isthmus ablation, 50 with electrode catheter cannulation into the VOM were analyzed. MB conduction was investigated by evaluating electrograms inside the VOM. Endocardial ablation was initially performed, followed by ablation inside the coronary sinus (CS), if required. Selective VOM-EI was performed if the MB potentials still exhibited early activation after radiofrequency ablation, suggesting the presence of MB connection bridging the mitral isthmus.
RESULTS
VOM electrograms composed of near-field MB and far-field left atrial potentials were recorded in all patients. Solely with endocardial ablation, 33 patients (66%) achieved entire mitral isthmus block, and 43 patients (86%) achieved an epicardial MB conduction block. MB potentials exhibited early activation in the remaining 7 (14%), even after requiring CS ablation. VOM-EI then was performed. Elimination of MB potentials was verified by electrode catheter reinsertion after VOM-EI. Mitral isthmus conduction was successfully blocked during VOM-EI in 4 patients and during additional radiofrequency ablation in the remaining 3. All patients finally achieved entire mitral isthmus block.
CONCLUSION
MB is effectively ablated by radiofrequency ablation. Continuous evaluation of MB conduction can reveal epicardial conduction and ablation effect. A residual MB epicardial connection is relatively rare but can be ablated by VOM-EI.
Identifiants
pubmed: 35367659
pii: S1547-5271(22)01872-0
doi: 10.1016/j.hrthm.2022.03.1228
pii:
doi:
Substances chimiques
Ethanol
3K9958V90M
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
1255-1262Informations de copyright
Copyright © 2022 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.