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Automatic detection of end QRS notching or slurring
Elaine N Clark1, Ibraheem Katibi2, Peter W Macfarlane1
1Institute of Cardiovascular and Medical Sciences, University of Glasgow, UK.
Automated detection of end QRS notching and slurring in electrocardiograms (ECGs) was developed and validated. The method achieved high accuracy, demonstrating its potential for clinical use in ECG analysis.
Area of Science:
- Cardiology
- Biomedical Engineering
- Signal Processing
Background:
- Electrocardiography (ECG) is crucial for diagnosing cardiac conditions.
- Subtle ECG waveform abnormalities, like QRS notching and slurring, can indicate underlying pathology.
- Accurate and automated detection of these findings is desirable for efficient clinical workflow.
Purpose of the Study:
- To establish criteria for the automated detection of end QRS notching and slurring.
- To assess the accuracy of an automated ECG analysis program for identifying these phenomena.
Main Methods:
- Developed automated detection criteria for end QRS notching and slurring.
- Utilized a training and testing dataset of 100 resting 12-lead ECGs from young adult men.
- Validated the automated method on independent Caucasian and Nigerian subject populations.
Main Results:
- The automated detection achieved high sensitivity (90.5-92.1%) and specificity (96.5-96.6%) in both training and test sets.
- Prevalence of notching/slurring (≥ 0.1 mV amplitude) was 23% in Caucasians and 29% in Nigerians.
- The automated method demonstrated consistent performance across different populations.
Conclusions:
- Automated detection of end QRS notching and slurring is feasible with high accuracy.
- This automated approach can aid in the efficient and reliable identification of ECG abnormalities.
- The findings support the integration of such algorithms into clinical ECG interpretation tools.
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