Factors affecting electrogram sensing in insertable cardiac monitor: Insights from surface electrocardiogram mapping analysis
Date
2023
Authors
Pitman, B.M.
Zanker, A.
Lim, M.
McLoughney, J.
Spinelli, J.
Tarone, R.
McInnes, K.
Heath, K.M.
Gieve, M.
Evans, S.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Heart Rhythm, 2023; 20(9):1297-1306
Statement of Responsibility
Bradley M. Pitman, Amy Zanker, Matthew Lim, Joshua McLoughney, Jade Spinelli, Rachel Tarone, Kristie McInnes, Kyle M. Heath, Mahsa Gieve, Shaun Evans, Glenn D. Young, Kurt C. Roberts-Thomson, Christopher X. Wong, Prashanthan Sanders, Dennis H. Lau
Conference Name
Abstract
Background: Fidelity of electrogram sensing may reduce false alerts from insertable cardiac monitor (ICM). Objective: To assess impact of vector length, implant angle and patient factors on electrogram sensing using surface electrocardiogram (EKG) mapping. Methods: Twelve separate precordial single-lead surface EKGs were acquired from 150 participants at two inter-electrode distance (75mm & 45mm), three vector angles (vertical, oblique, horizontal) and in two postures (upright & supine). A subset of fifty patients also received a clinically indicated ICM implant in 1:1 ratio (Medtronic Reveal LINQ:Biotronik Biomonitor III). All EKG and ICM electrogram were analyzed by blinded investigators using DigitizeIt software. P-wave visibility threshold was set at >0.015mV. Logistic regression was used to identify factors impacting P-wave amplitude. Results: A total of 1,800 tracings from 150 participants [44.5% female, median 59 years old] were assessed. Median P- and R-wave were 45% and 53% larger with vector length of 75 vs. 45mm respectively (both p<0.001). The oblique orientation yielded the best P- and R-wave sensing while posture change did not impact on P-wave amplitude. Mixed effects modeling found that visible P-waves occur more frequently with vector length of 75mm than 45mm (86% vs. 75% respectively, p<.0001). A longer vector length improved both P-wave amplitude and visibility in all BMI categories. There was moderate correlation of P- and R-waves from the ICM electrogram to surface EKG recordings (ICC 0.74 and 0.80, respectively). Conclusion: Longer vector length and oblique implant angle yielded the best electrogram sensing and are relevant considerations for ICM implantations.
School/Discipline
Dissertation Note
Provenance
Description
Published September 2023
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© 2023 Heart Rhythm Society. All rights reserved.