Enhanced Arrhythmia Classification through Feature Engineering and Hierarchical Modeling

Cardiac arrhythmias, characterized by irregular heart rhythms, pose a considerable challenge in medical diagnostics due to their diverse and subtle manifestations. Traditional machine learning models, while effective in detecting arrhythmias from electrocardiograms (ECGs), often struggle with these nuances. This study proposes a method that combines sophisticated feature engineering and hierarchical classification to enhance arrhythmia classification. Utilizing a comprehensive ECG database from Chapman University and Shaoxing People’s Hospital, we analyzed the data from 10,646 patients, encompassing 11 types of arrhythmic rhythms along with additional cardiovascular conditions. Data preprocessing involved outlier removal, feature encoding, and the introduction of novel features such as the disparity between atrial and ventricular rates and the Q wave ratio. These new features were crucial in discerning heart rhythm discrepancies. To achieve robust classification, the study employed Random Forest and XGBoost algorithms. A two-tier hierarchical classification model was introduced, initially classifying cardiac rhythms into classes and another model delving into finer distinctions among specific classes. This approach was further enhanced by several oversampling techniques to address varied data distributions across different classes. The results revealed notable improvements in model performance with the integration of new features, yielding increased accuracy and f1-scores. The research, while achieving significant advancements in arrhythmia classification, highlighted the need for further studies with more diverse datasets for broader applicability. The study demonstrates the potential of integrating machine learning with domain-specific features, suggesting a promising direction for advanced diagnostic tools in cardiology, with the potential to improve patient outcomes in arrhythmia treatment.