Three-Dimensional Cardiac Mapping Characterizes Ventricular Contractile Patterns during Cardiac Resynchronization...

Area of Science:

• Cardiology
• Medical Devices
• Electrophysiology

Background:

• Electroanatomic mapping systems are used to track electrode positions within the heart.
• Assessing left ventricular (LV) performance during cardiac resynchronization therapy (CRT) implantation is crucial.
• This study explored using CRT lead motion for ventricular contractility surrogates.

Purpose of the Study:

• To evaluate the feasibility of characterizing LV performance during CRT implant.
• To utilize electroanatomic mapping to track CRT lead motion.
• To derive ventricular contractility surrogates from lead movement.

Main Methods:

• Electrodes for atrial, right ventricular (RV), and LV pacing were connected to the EnSite NavX™ mapping system.
• Relative electrode displacement was averaged over 10 cycles during RV, LV, and biventricular (BiV) pacing.
• Three contractility surrogates (systolic slope, time to peak systolic contraction, fractional shortening) were derived from RV-LV distance waveforms.

Main Results:

• Detectable differences in contractility surrogates were observed across different pacing configurations in 20 patients.
• Median variations for systolic slope, time to peak systolic contraction, and fractional shortening were 42%, 35%, and 19%, respectively.
• RV-LV distance waveforms demonstrated stability and sensitivity to pacing timing cycles.

Conclusions:

• Tracking CRT pacing electrode motion with a mapping system is a feasible method.
• This technique allows for the derivation of contractility surrogates during implant.
• This approach offers a novel way to assess ventricular performance during CRT procedures.