Septal Substrate Ablation Guided by Delayed Transmural Conduction Times: A Novel Ablation Approach to Target Intramural Substrates.
Publication/Presentation Date
9-1-2023
Abstract
BACKGROUND: Intraprocedural identification of intramural septal substrate for ventricular tachycardia (ISS-VT) in nonischemic cardiomyopathy (NICM) is challenging. Delayed (>40 ms) transmural conduction time (DCT) with right ventricular basal septal pacing has been previously shown to identify ISS-VT.
OBJECTIVES: This study sought to determine whether substrate catheter ablation incorporating areas of DCT may improve acute and long-term outcomes.
METHODS: We included patients with NICM and ISS-VT referred for catheter ablation between 2016 and 2020. ISS-VT was defined by the following: 1) confluent septal areas of low unipolar voltage (< 8.3 mV) in the presence of normal or minimal bipolar abnormalities; and 2) presence of abnormal electrograms in the septum. Substrate ablation was guided by the following: 1) activation and/or entrainment mapping for tolerated VT and pace mapping with ablation of abnormal septal electrograms for unmappable VTs (n = 57, Group 1); and 2) empirically extended to target areas of DCT during right ventricular basal septal pacing regardless of their participation in inducible VT(s) but sparing the conduction system when possible (n = 24, Group 2).
RESULTS: There were no significant baseline differences between Groups 1 and 2. Noninducibility of any VT programmed stimulation at the end of ablation was higher in Group 2 compared with Group 1 (80% vs 53%; P = 0.03). At 12-month follow-up, single-procedure VT-free survival was significantly higher (79% vs 46%; P = 0.006) and the time to VT recurrence was longer (mean 10 ± 3 months vs 7 ± 4 months; P = 0.02) in Group 2 compared with Group 1.
CONCLUSIONS: In patients with NICM and ISS-VT, a substrate ablation strategy that incorporates areas of DCT appears to improve freedom from recurrent VT.
Volume
9
Issue
9
First Page
1903
Last Page
1913
ISSN
2405-5018
Published In/Presented At
Arceluz, M. R., Thind, M., Hambach, B., Garcia, F. C., Callans, D. J., Guandalini, G. S., Frankel, D. S., Supple, G. E., Hyman, M., Schaller, R. D., Nazarian, S., Dixit, S., Lin, D., Marchlinski, F. E., & Santangeli, P. (2023). Septal Substrate Ablation Guided by Delayed Transmural Conduction Times: A Novel Ablation Approach to Target Intramural Substrates. JACC. Clinical electrophysiology, 9(9), 1903–1913. https://doi.org/10.1016/j.jacep.2023.05.028
Disciplines
Education | Medical Education
PubMedID
37480866
Department(s)
Department of Education
Document Type
Article