The Accuracy of Cardiac Surface Conduction Velocity Measurements

Abstract

AbstractBackground:Conduction velocity (CV) is a measure of the health of myocardial tissue. It can be measured by taking differences in activation times from intracardiac electrodes. Several factors introduce error into the measurement, amongst which, ignoring the three dimensional aspect is a major detriment. The purpose of this paper was to determine if, nonetheless, there was a specific region where CV could be accurately measured.Methods:Computer simulations of three dimensional ventricles with a realistic His-Purkinje system were performed. Ventricles also included a dense scar or diffuse fibrosis.Results:A finer spatial sampling produced better agreement with true CV. Using a error limit of 10 cm/s as a threshold, measurements taken within a region less than 2 cm from the pacing site proved to be accurate. Error increased abruptly beyond this distance. The Purkinje system and tissue fibre orientation played equally major roles in leading to a surface CV which was not reflective of the CV propagation through the tissue.Conclusions:Surface CV measurements close to the pacing site taken with an electrode spacing of at most 1 mm, give reasonable estimates of tissue CV.