A Matlab program to quantify low-SNR pacemaker signals

In an attempt to study the influence of varying distances between bipolar atrial pacemaker electrodes on ventricular far-field oversensing, we have chosen to analyse signals recorded directly from the patients cardiac pacemaker, via its programmer unit, to a digital acquisition board under several test conditions. This data is analysed by a GUI-driven Matlab program for their near- and far-field parameters spike amplitude and width, frequency of occurrence, and average potential shape. Far-field events are displayed together with their preceding near-field over the whole recording period by a raster-plot display. Our Matlab routines were tested on several patients with a DDDR type pacemaker, but an extensive study under controlled conditions is pending.