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Severe Atrioventricular Decoupling, Uncoupling, and Ventriculoatrial Coupling During Enhanced Atrial Pacing: Incidence, Mechanisms, and Implications for Minimizing Right Ventricular Pacing in ICD Patients
Author(s) -
SWEENEY MICHAEL O.,
ELLENBOGEN KENNETH A.,
TANG ANTHONY S.L.,
JOHNSON JAMES,
BELK PAUL,
SHELDON TODD
Publication year - 2008
Publication title -
journal of cardiovascular electrophysiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.193
H-Index - 138
eISSN - 1540-8167
pISSN - 1045-3873
DOI - 10.1111/j.1540-8167.2008.01226.x
Subject(s) - medicine , cardiology , ventricular pacing , decoupling (probability) , anesthesia , heart failure , control engineering , engineering
Background:Enhanced AAI/R pacing minimizes right ventricular pacing but may permit or induce AV decoupling (AV‐DC) due to unrestricted AV intervals (AVIs). The purpose of this study was to characterize and quantify AVI behavior in a randomized trial of enhanced AAI/R pacing in ICD patients.Methods:One hundred twenty‐one patients in the Marquis ICD MVP™ Study, a randomized 1‐month crossover comparison of cumulative% ventricular pacing (Cum%VP) in enhanced AAIR (MVP) vs DDD/R, were analyzed. AV‐DC was defined as ≥40% AVIs >300 ms; VA coupling (VA‐C) was defined as%V‐atrial pace (AP) intervals <300 ms. Dynamic AVI behavior and increases in Cum%VP due to AV block (AV uncoupling, AV‐UC) were characterized using Holters with real‐time ICD telemetry.Results:AV‐DC occurred in 17 (14%) of patients. Baseline PR, amiodarone, nighttime, lower rate >60 beats/min, rate response, and Cum%AP were associated with longer AVIs. Logistic regression identified baseline PR (odds ratio [OR]= 1.024, 95% confidence interval [CI] 1.007–1.042; P = 0.005), and Cum%AP (OR = 1.089, 95% CI 1.027–1.154; P = 0.004) as predictors of AV‐DC. AV‐DC was associated with ≈10‐fold increases in both Cum%VP (13.6 ± 28.3% vs 1.2 ± 3.9%; P = 0.023) due to transient AV‐UC) and VA‐C (6.0 ± 17.5% vs 0.5 ± 1.2%, P = 0.028). AV coupling (<40% AVIs >300 ms) was preserved in 104 (86%) patients.Conclusions:AV‐DC, VA‐C, and AV‐UC may be worsened or induced by enhanced AAI/R pacing. Conservative programming of lower rate and rate response should reduce the risk of AV‐DC by reducing Cum%AP.