Related Experiment Video
Updated: Jul 31, 2026

Analyzing Long-Term Electrocardiography Recordings to Detect Arrhythmias in Mice
Published on: May 23, 2021
Computer-assisted ECG interpretation for confirmation of premature atrial complexes
C W Musser1, T W Simmons, W K Haisty
1Department of Medicine, Section of Cardiology, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
Unlabelled:
Current programs for computerized ECG analysis are not interactive. We developed custom software for computer-assisted ECG interpretation that functioned interactively with an observer directing the computerized process. The software was first used for recognition of PACs superimposed on ST-T waveforms. The interactive process included 6 steps. 1) The computer displayed the 12-lead ECG and the user selected the most frequent QRS-T waveforms for averaging. 2) The computer generated and displayed the averaged QRS-T waveform. 3) The user selected waveforms suspected to have PACs superimposed on the ST-T segments. 4) The computer generated and displayed the difference waveform by subtracting the average waveform from the suspect waveforms. 5) The user recognized and p-waves in the difference waveform and marked the onset and offset by positioning the cursor and clicking. 6) The computer then measured p-wave amplitudes, durations, and areas and displayed the recognized p-wave. The program was developed using digital data from 2 ECGs and tested on 39 ECGs with suspected PACs and 26 control ECGs.
Results:
The software and user interaction recognized 79 PACs in the suspect group. Control ECGs were analyzed using 3 complexes with the same leads and onsets as the test group. Of the 79 PACs found in the suspect group, mean values included an area under the curve of 4.0 +/- 3.2 microV-s for the test group versus 0.4 +/- 0.4 microV-s for the control (P < 0.001) and peak-to-trough voltage amplitudes of 104 +/- 66 microV versus 15 +/- 7 microV for the control (P < 0.001). The average time of onset of the premature complexes was 282 +/- 120 msec, and their duration was 100 +/- 28 msec.
Conclusion:
Custom software combined the superior human pattern recognition with the digital signal processing of the computer. This enhanced recognition of ectopic atrial activity.
Related Concept Videos
Electrocardiogram
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...
Correlation between ECG and Cardiac Cycle
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
Electrocardiogram Fundamentals
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin to...
ECG Interpretation of Rhythms
Components of the Electrocardiogram
The primary components of a normal ECG waveform in Normal sinus rhythm(NSR) include the P wave, PR interval, QRS complex, ST segment, T wave, and occasionally a U wave.
ECG waveforms are divided by vertical and horizontal lines at standard intervals.
The horizontal axis measures time and rate, and the vertical axis measures amplitude or voltage. When...
Dysrhythmias V: Evaluating Dysrhythmias
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias

