Estimation of conduction velocity vector fields from epicardial mapping data

Abstract

An automated method to estimate vector fields of propagation velocity from observed epicardial extracellular potentials is introduced. The method relies on fitting polynomial surfaces T(x, y) to the space-time (x, y, t) coordinates of activity. Both speed and direction of propagation are computed from the gradient of the local polynomial surface. The components of velocity, which are total derivatives, are expressed in terms of the partial derivatives which comprise the gradient of T. The method was validated on two-dimensional (2-D) simulations of propagation and then applied to cardiac mapping data. Conduction velocity was estimated at multiple epicardial locations during sinus rhythm, pacing, and ventricular fibrillation (VF) in pigs. Data were obtained via a 528-channel mapping system from 23 x 22 and 24 x 21 arrays of unipolar electrodes sutured to the right ventricular epicardium. Velocity estimates are displayed as vector fields and are used to characterize propagation qualitatively and quantitatively during both simple and complex rhythms.

Prediction model of sinoatrial node field potential using high order partial least squares

“…Both of the first two wave peaks KDG WLPH LQWHUYDOV ǻW DQG ǻW ZKLFK meant that these two kinds of wave peaks were conductive. Figure 1(b) showed the conducting directions and velocities [14] of the first positive wave peak. In the center, there were no time intervals.…”

Regional Conduction Velocity Calculation based on Local Activation Times: A Simulation Study on Clinical Geometries

“…The analysis of regional CV gives insight into the behavior of the tissues beneath that region. There exist methods to calculate the CV in clinical as well as simulated environments [1][2][3]. In this work the regional CV has been calculated for simulated LAT on clinical geometries.…”

“…The incidence of AF increases with age and can lead to stroke as well as reduced quality of life [4]. CV is a parameter that represents the magnitude and direction of the propagation of depolarization wavefronts on the atrium and the calculation of CV is a measure for the atrial substrate [1,2]. The analysis of regional CV gives insight into the behavior of the tissues beneath that region.…”

“…The most common cardiac arrhythmia is atrial fibrillation (AF) [1]. The incidence of AF increases with age and can lead to stroke as well as reduced quality of life [4].…”

Software design for analysis of multichannel intracardial and body surface electrocardiograms

“…Recordings with over 500 leads have been reported [1]. Our group records mapping data with 64 up to 247 leads which are sampled with frequencies ranging from 0.5 to 4 kHz and 8, 14, and 16-bit resolution at bit steps of 0.73 up to 40 mV [2].…”