A computer based system for the study of QT intervals

Abstract

Recent research suggests that the dispersion of QT intervals across 12 leads of the standard electrocardiogram (ECG) is a clinically important indicator of the susceptibility of patients to serious ventricular arrhythmias. This hypothesis can be further tested by measuring E C G from large clinical trials in which outcome is known for each patient. These ECGs are stored on paper. We have developed a system which scans ECG waveforms stored on paper, ana' converts them to digital data stored on computer. The system which incorporates a user-interface, enables quick and reliable measurements of QT intervals, thereby replacing the tedious and potentially insensitive method of hand measurements. Preliminary results of comparison between hand and user-interactive measurements are presented to show the accuracy and characteristics of the system.

Shape-based Matching of ECG Recordings

“…A number of research and commercial systems exist for digitizing ECG waveforms on hardcopy printouts [18], [5], [13], [12], [14], [15], [16], [4]. They typically start by detecting the ECG waveform and separating it from the background grid, usually via color segmentation or a morphological operator [12].…”

“…They typically start by detecting the ECG waveform and separating it from the background grid, usually via color segmentation or a morphological operator [12]. Once detected, the waveform pixels are thinned [5], if necessary, and traced using line tracking [14] or more advanced model fitting such as snakes [4]. The greatest limitation of existing approaches is the need for manual intervention, especially to locate bounding boxes around the lead waveforms.…”