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Left Ventricular Paced Activation in Cardiac Resynchronization Therapy Patients with Left Bundle Branch Block and Relationship to Its Electrical Substrate

Overview
Journal Heart Rhythm O2
Date 2021 Jun 11
PMID 34113862
Citations 8
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Abstract

Background: Cardiac resynchronization therapy (CRT) uses left ventricular (LV) pacing to restore rapid synchronized LV activation when it is delayed in patients with myocardial disease.

Objective: Although intrinsic LV activation delays are understood, little is known about reactions to LV stimulation and whether they are affected by QRS duration (QRSd), morphology, LV substrate, or choice of electrode pair. The purpose of this study was to test these interactions.

Methods: In 120 heart failure patients with left bundle branch block (LBBB) and QRS >120 ms receiving CRT with quadripolar LV leads, device-based measurements of intrinsic activation delay (qLV) and paced inter- (and intra-) LV conduction times were evaluated at the proximal and distal LV bipoles.

Results: During intrinsic conduction, qLV varied little between the proximal and distal pairs in patients with LBBB (n = 120; age 68 ± 11 years; 63% male; ejection fraction 25% ± 7%; 33% ischemic cardiomyopathy; QRSd 162 ± 19 ms). A minority (30%) had conduction barriers (ie, gradients) (ΔqLV 29 ± 8 ms vs 9 ± 5 ms in patients without gradients; <.01), which occurred equally in ischemic and nonischemic patients. A majority were functional (and not scar-mediated), as they resolved with pacing in most patients (75%). Importantly, LV-paced conduction times were unrelated to baseline QRS morphology (LBBB 166 ± 30 ms vs RBBB control 172 ± 30 ms; = NS), longer than intrinsic conduction (166 ± 30 ms vs 129 ± 28 ms; <.01), and varied significantly by electrode pair (ie, small distances) and etiology. Correlation between intrinsic activation delay (qLV) and LV-paced conduction time was poor (R = 0.278; <.05).

Conclusion: LV-paced effect, which is core to CRT, is unpredictable based on conventionally used measures and should be considered during CRT optimization.

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References
1.
Strik M, van Deursen C, van Middendorp L, van Hunnik A, Kuiper M, Auricchio A . Transseptal conduction as an important determinant for cardiac resynchronization therapy, as revealed by extensive electrical mapping in the dyssynchronous canine heart. Circ Arrhythm Electrophysiol. 2013; 6(4):682-9. DOI: 10.1161/CIRCEP.111.000028. View

2.
Hsing J, Selzman K, Leclercq C, Pires L, McLaughlin M, McRae S . Paced left ventricular QRS width and ECG parameters predict outcomes after cardiac resynchronization therapy: PROSPECT-ECG substudy. Circ Arrhythm Electrophysiol. 2011; 4(6):851-7. DOI: 10.1161/CIRCEP.111.962605. View

3.
Vernooy K, Verbeek X, Cornelussen R, Dijkman B, Crijns H, Arts T . Calculation of effective VV interval facilitates optimization of AV delay and VV interval in cardiac resynchronization therapy. Heart Rhythm. 2007; 4(1):75-82. DOI: 10.1016/j.hrthm.2006.09.007. View

4.
Ginks M, Shetty A, Lambiase P, Duckett S, Bostock J, Peacock J . Benefits of endocardial and multisite pacing are dependent on the type of left ventricular electric activation pattern and presence of ischemic heart disease: insights from electroanatomic mapping. Circ Arrhythm Electrophysiol. 2012; 5(5):889-97. DOI: 10.1161/CIRCEP.111.967505. View

5.
Feeny A, Rickard J, Patel D, Toro S, Trulock K, Park C . Machine Learning Prediction of Response to Cardiac Resynchronization Therapy: Improvement Versus Current Guidelines. Circ Arrhythm Electrophysiol. 2019; 12(7):e007316. PMC: 6588175. DOI: 10.1161/CIRCEP.119.007316. View