Characterization of ventricular activation pattern and acute hemodynamics during multipoint left ventricular pacing

Area of Science:

• Cardiology
• Medical Devices
• Electrophysiology

Background:

• Multipoint Pacing (MPP) is a novel cardiac resynchronization therapy (CRT) using a single coronary sinus branch.
• MPP is hypothesized to enhance left ventricular (LV) function by increasing LV tissue capture and promoting uniform ventricular wavefront propagation compared to biventricular pacing (BIV).

Purpose of the Study:

• To evaluate the mechanisms and effects of MPP in CRT using contact mapping and hemodynamic measurements.
• To compare the efficacy of MPP against conventional BIV pacing.

Main Methods:

• Ten patients with non-ischemic cardiomyopathy received a CRT-defibrillator capable of MPP.
• An acute pacing protocol involved 2 BIV and up to 9 MPP interventions.
• LV electrical activation patterns and hemodynamics (dP/dtmax) were assessed and compared between MPP and BIV.

Main Results:

• MPP significantly increased LV dP/dtmax (30% ± 13% vs. 25% ± 11%) and reduced QRS duration (22% ± 11% vs. 11% ± 11%) compared to BIV.
• MPP demonstrated a decrease in total endocardial activation time (25% ± 15% vs. 10% ± 20%).
• MPP achieved larger LV mass capture earlier (35% ± 22% at 25ms; 78% ± 27% at 50ms), indicating quicker LV wavefront propagation.

Conclusions:

• In this acute study, MPP significantly improved endocardial and surface electrical parameters in CRT patients compared to BIV.
• MPP demonstrated superior hemodynamic improvements over BIV pacing.