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Automated differentiation of wide QRS complex tachycardia using QRS complex polarity
Adam M May1, Bhavesh B Katbamna2, Preet A Shaikh3
1Department of Medicine, Division of Cardiovascular Diseases, Washington University School of Medicine in St. Louis, St. Louis, MO, USA. may.adam@wustl.edu.
Automated algorithms using QRS polarity direction and shifts improve the differentiation of wide QRS complex tachycardia (WCT). These novel approaches enhance computerized ECG interpretation for better ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) diagnosis.
Area of Science:
- Cardiology
- Medical Informatics
- Artificial Intelligence in Medicine
Background:
- Differentiating wide QRS complex tachycardia (WCT) into ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) is clinically challenging.
- Existing 12-lead electrocardiogram (ECG) criteria and algorithms have limitations in accuracy.
- Computerized ECG interpretation (CEI) with engineered features offers a path to improve diagnostic accuracy.
Purpose of the Study:
- To develop and validate automated algorithms for WCT differentiation.
- To utilize novel engineered features: WCT QRS polarity Code (WCT-PC) and QRS Polarity Shift (QRS-PS).
- To compare the performance of machine learning models using these engineered features.
Main Methods:
- A three-part study employing machine learning (ML) models including logistic regression, artificial neural network, Random Forests, support vector machine, and ensemble learning.
- Engineered features (WCT-PC, QRS-PS) and established WCT differentiation features were used.
- Models were trained and validated using WCT ECG measurements alone, paired WCT and baseline ECG features, and combined features.
Main Results:
- Models using WCT ECG features alone achieved Area Under the Curve (AUC) of 0.86-0.88.
- Pairing WCT and baseline ECG features improved accuracy, with AUCs ranging from 0.90-0.93.
- Random Forests and Support Vector Machine models demonstrated the best performance in Part 3, with AUCs up to 0.93.
Conclusions:
- Engineered parameters focusing on QRS polarity direction and shifts are effective for WCT differentiation.
- These novel features show promise for enhancing automated CEI algorithms.
- The proposed automated algorithms represent a practical advancement in WCT diagnosis.
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