title: Conduction velocity restitution of the human atrium--an efficient measurement protocol for clinical electrophysiological studies.
abstract: 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.
authors.affiliation: Institute of Biomedical Engineering, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany. frank.m.weber@kit.edu
authors.forename: Frank M
authors.initials: FM
authors.lastname: Weber
authors.forename: Armin
authors.initials: A
authors.lastname: Luik
authors.forename: Christopher
authors.initials: C
authors.lastname: Schilling
authors.forename: Gunnar
authors.initials: G
authors.lastname: Seemann
authors.forename: Martin W
authors.initials: MW
authors.lastname: Krueger
authors.forename: Cristian
authors.initials: C
authors.lastname: Lorenz
authors.forename: Claus
authors.initials: C
authors.lastname: Schmitt
authors.forename: Olaf
authors.initials: O
authors.lastname: Dossel
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D017115:Catheter Ablation; D004562:Electrocardiography / Q000379:methods*; D006321:Heart / Q000503:physiopathology*; D006325:Heart Atria / Q000503:physiopathology; D006329:Heart Conduction System / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D015203:Reproducibility of Results; D013610:Tachycardia / Q000503:physiopathology; D058067:Wavelet Analysis