Radiofrequency ablation of the diseased human left ventricle
Radiofrequency ablation of the diseased human left ventricle
Background: predictors of effective ablation lesion delivery in the human left ventricle are not established, particularly in scar. Impedance drop and electrogram (EGM) attenuation are potential surrogates to assess this.
Objectives: this study sought to establish the relationships between ablation index (AI) and force-time integral (FTI) with impedance drop and EGM attenuation in the human left ventricle.
Methods: patients undergoing ventricular tachycardia ablation were recruited. EGMs were collected preablation and postablation, with impedance, AI, and FTI measured during. Based on preablation bipolar voltage, myocardium was adjudged a low-voltage myocardium (LVM) (1.50 mV). Relationships between these parameters were explored.
Results: a total of 402 ablations were analyzed in 15 patients. The percent impedance drop correlated with AI and FTI (P < 0.0005; repeated-measures correlation coefficient: 0.54 and 0.44, respectively), a relationship that became weaker with increased myocardial fibrosis, (repeated-measures correlation coefficient for NVM, IVM, and LVM, AI: 0.67, 0.60, and 0.52, respectively; FTI: 0.59, 0.51, and 0.42, respectively). The curve between AI/FTI and impedance drop plateaued at 763 AI and 713 gram-seconds, an impedance drop of 7.5%. Shallower curves occurred progressively from NVM to LVM (P < 0.0005). Mixed models demonstrated that AI and FTI had a greater effect on impedance drop than myocardial fibrosis, drift, or orientation, (standardized β: 0.54 and 0.48, respectively). EGMs were attenuated with ablation (29.3%; IQR: 4.4%-53.3%; P < 0.0005), but attenuation did not correlate with AI or FTI.
Conclusions: on biophysical analysis, ablation beyond an AI of 763 and FTI of 713 gs offers minimal additional efficacy on average. Fibrosis blunts ablation efficacy. AI is a stronger correlate with impedance drop than FTI. EGM attenuation does not correlate with ablation parameters. (Late Potentials and Ablation Index in Ventricular Tachycardia Ablation; NCT03437408)
330-340
Bates, Alexander P.
41111d45-1589-4fdd-a5b4-1732a38857ac
Paisey, John
76e6e4ec-eca8-46d4-b079-f4ffb7f953cf
Yue, Arthur
6bab01eb-b37c-4722-8e89-fa347e895e38
Banks, Phil
41d5666b-582d-4bfc-9f0a-78c84ffda976
Roberts, Paul R.
32fe1d97-dc53-49a1-9b4a-f866d0b7d13d
Ullah, Waqas
623bb2d2-b74f-46ca-bf12-e51108684dfc
27 March 2023
Bates, Alexander P.
41111d45-1589-4fdd-a5b4-1732a38857ac
Paisey, John
76e6e4ec-eca8-46d4-b079-f4ffb7f953cf
Yue, Arthur
6bab01eb-b37c-4722-8e89-fa347e895e38
Banks, Phil
41d5666b-582d-4bfc-9f0a-78c84ffda976
Roberts, Paul R.
32fe1d97-dc53-49a1-9b4a-f866d0b7d13d
Ullah, Waqas
623bb2d2-b74f-46ca-bf12-e51108684dfc
Bates, Alexander P., Paisey, John, Yue, Arthur, Banks, Phil, Roberts, Paul R. and Ullah, Waqas
(2023)
Radiofrequency ablation of the diseased human left ventricle.
JACC: Clinical Electrophysiology, 9 (3), .
(doi:10.1016/j.jacep.2022.10.001).
Abstract
Background: predictors of effective ablation lesion delivery in the human left ventricle are not established, particularly in scar. Impedance drop and electrogram (EGM) attenuation are potential surrogates to assess this.
Objectives: this study sought to establish the relationships between ablation index (AI) and force-time integral (FTI) with impedance drop and EGM attenuation in the human left ventricle.
Methods: patients undergoing ventricular tachycardia ablation were recruited. EGMs were collected preablation and postablation, with impedance, AI, and FTI measured during. Based on preablation bipolar voltage, myocardium was adjudged a low-voltage myocardium (LVM) (1.50 mV). Relationships between these parameters were explored.
Results: a total of 402 ablations were analyzed in 15 patients. The percent impedance drop correlated with AI and FTI (P < 0.0005; repeated-measures correlation coefficient: 0.54 and 0.44, respectively), a relationship that became weaker with increased myocardial fibrosis, (repeated-measures correlation coefficient for NVM, IVM, and LVM, AI: 0.67, 0.60, and 0.52, respectively; FTI: 0.59, 0.51, and 0.42, respectively). The curve between AI/FTI and impedance drop plateaued at 763 AI and 713 gram-seconds, an impedance drop of 7.5%. Shallower curves occurred progressively from NVM to LVM (P < 0.0005). Mixed models demonstrated that AI and FTI had a greater effect on impedance drop than myocardial fibrosis, drift, or orientation, (standardized β: 0.54 and 0.48, respectively). EGMs were attenuated with ablation (29.3%; IQR: 4.4%-53.3%; P < 0.0005), but attenuation did not correlate with AI or FTI.
Conclusions: on biophysical analysis, ablation beyond an AI of 763 and FTI of 713 gs offers minimal additional efficacy on average. Fibrosis blunts ablation efficacy. AI is a stronger correlate with impedance drop than FTI. EGM attenuation does not correlate with ablation parameters. (Late Potentials and Ablation Index in Ventricular Tachycardia Ablation; NCT03437408)
Text
VT Parameters JACC EP Proof
- Proof
Restricted to Repository staff only
Request a copy
More information
Accepted/In Press date: 3 October 2022
e-pub ahead of print date: 10 October 2022
Published date: 27 March 2023
Identifiers
Local EPrints ID: 486825
URI: http://eprints.soton.ac.uk/id/eprint/486825
ISSN: 2405-500X
PURE UUID: 650ed383-fc81-4464-935d-1a22c8d8543d
Catalogue record
Date deposited: 06 Feb 2024 17:49
Last modified: 17 Mar 2024 07:21
Export record
Altmetrics
Contributors
Author:
Alexander P. Bates
Author:
John Paisey
Author:
Arthur Yue
Author:
Phil Banks
Author:
Paul R. Roberts
Author:
Waqas Ullah
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics