Evaluating multisite pacing strategies in cardiac resynchronization therapy in the preclinical setting

Luuk I B Heckman; Marion Kuiper; Frederic Anselme; Filippo Ziglio; Nicolas Shan; Markus Jung; Stef Zeemering; Kevin Vernooy; Frits W Prinzen

doi:10.1016/j.hroo.2020.03.003

Evaluating multisite pacing strategies in cardiac resynchronization therapy in the preclinical setting

Heart Rhythm O2. 2020 Jun 15;1(2):111-119. doi: 10.1016/j.hroo.2020.03.003. eCollection 2020 Jun.

Authors

Affiliations

¹ Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.
² Department of Cardiology, Rouen Hospital, Rouen, France.
³ MicroPort CRM, Clamart, France.
⁴ Heraeus, Hanau, Germany.
⁵ Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre+ (MUMC+), Maastricht, The Netherlands.
⁶ Department of Cardiology, Radboud University Medical Centre (Radboudumc), Nijmegen, The Netherlands.

Abstract

Background: Multisite pacing strategies that improve response to cardiac resynchronization therapy (CRT) have been proposed. Current available options are pacing 2 electrodes in a multipolar lead in a single vein (multipoint pacing [MPP]) and pacing using 2 leads in separate veins (multizone pacing [MZP]).

Objective: The purpose of this study was to compare in a systematic manner the acute hemodynamic response (AHR) and electrophysiological effects of MPP and MZP and compare them with conventional biventricular pacing (BiVP).

Methods: Hemodynamic and electrophysiological effects were evaluated in a porcine model of acute left bundle branch block (LBBB) (n = 8). AHR was assessed as LVdP/dtmax. Activation times were measured using >100 electrodes around the epicardium, measuring total activation time (TAT) and left ventricular activation time (LVAT).

Results: Compared to LBBB, BiVP, MZP, and MPP reduced TAT by 26% ± 10%, 32% ± 13%, and 32% ± 14%, respectively (P = NS between modes) and LVAT by 4% ± 5%, 11% ± 5%, and 12% ± 5%, respectively (P <.05 BiVP vs MPP and MZP). On average, BiVP increased LVdP/dtmax by 8% ± 4%, and optimal BiVP increased LVdP/dtmax by 13% ± 4%. The additional improvement in LVdP/dtmax by MZP and MPP was significant only when its increase during BiVP and decrease in TAT were poor (lower 25% of all sites in 1 subject). The increase in LVdP/dtmax was larger when large interelectrode distances (>5 cm vs <2.2 cm) were used.

Conclusion: In this animal model of acute LBBB, MPP and MZP create similar degrees of electrical resynchronization and hemodynamic effect, which are larger if interelectrode distance is large. MPP and MZP increase the benefit of CRT only if the left ventricular lead used for BiVP provides poor response.

Keywords: Acute hemodynamics; Cardiac resynchronization therapy; Electrical mapping; Multipoint pacing; Multizone pacing.