In-vivo measurement using standard circular catheters showed that reducing pacing cycle length from 500 to 300 ms decreased local conduction velocity by 20 ± 15% and global CV by 17 ± 13%.
Observational (n=5)
Does a cosine-fit method using standard circular catheters allow for efficient in-vivo measurement of conduction velocity restitution in patients undergoing catheter ablation?
A simple cosine-fit method using standard circular catheters allows for feasible in-vivo measurement of absolute conduction velocity and restitution during clinical electrophysiological procedures.
Conduction velocity (CV) and CV restitution are important substrate parameters for understanding atrial arrhythmias. The aim of this work is to (i) present a simple but feasible method to measure CV restitution in-vivo using standard circular catheters, and (ii) validate its feasibility with data measured during incremental pacing. From five patients undergoing catheter ablation, we analyzed eight datasets from sinus rhythm and incremental pacing sequences. Every wavefront was measured with a circular catheter and the electrograms were analyzed with a cosine-fit method that calculated the local CV. For each pacing cycle length, the mean local CV was determined. Furthermore, changes in global CV were estimated from the time delay between pacing stimulus and wavefront arrival. Comparing local and global CV between pacing at 500 and 300 ms, we found significant changes in seven of eight pacing sequences. On average, local CV decreased by 20 ± 15% and global CV by 17 ± 13%. The method allows for in-vivo measurements of absolute CV and CV restitution during standard clinical procedures. Such data may provide valuable insights into mechanisms of atrial arrhythmias. This is important both for improving cardiac models and also for clinical applications, such as characterizing arrhythmogenic substrates during sinus rhythm.
Weber et al. (Tue,) conducted a observational in Atrial arrhythmias (n=5). In-vivo measurement of conduction velocity restitution using standard circular catheters vs. Pacing at 500 ms vs 300 ms was evaluated on Changes in local and global conduction velocity between pacing at 500 and 300 ms. In-vivo measurement using standard circular catheters showed that reducing pacing cycle length from 500 to 300 ms decreased local conduction velocity by 20 ± 15% and global CV by 17 ± 13%.