Deep Learning-Based ECG Signal Classification for Automated Cardiac Arrhythmia Detection
Author(s):Rajesh Kumar Anil Kumar Tiwari
Affiliation: Department of Biomedical Engineering, Maulana Azad National Institute of Technology, Bhopal, Madhya Pradesh, India Department of Electronics and Communication Engineering, National Institute of Technology, Rourkela, Odisha, India
Page No: 49-59
Volume issue & Publishing Year: Volume 3, Issue 6, June 2026
published on: 2026/06/14
Journal: International Journal of Advanced Multidisciplinary Application.(IJAMA)
ISSN NO: 3048-9350
DOI:
Abstract:
Cardiac arrhythmias represent a leading cause of sudden cardiac death worldwide, affecting approximately 300,000 individuals annually in India alone. Conventional manual interpretation of 12-lead electrocardiogram (ECG) signals demands considerable clinical expertise and is susceptible to inter-observer variability, motivating the development of automated classification systems capable of consistent, rapid analysis across diverse patient populations and healthcare settings. This study presents a novel hybrid deep learning architecture combining one-dimensional convolutional neural networks (1D-CNN) and bidirectional long short-term memory (BiLSTM) networks for automated multi-class arrhythmia classification from 12-lead ECG recordings. The proposed framework incorporates a multi-scale feature extraction module, an attention mechanism for lead-specific saliency weighting, and a cascaded classification head optimised for class imbalance. The model was trained and validated on a composite dataset of 27,367 annotated 12-lead ECG recordings drawn from the PhysioNet Computing in Cardiology Challenge 2020 database, covering seven clinically significant rhythm classes: normal sinus rhythm, atrial fibrillation, ventricular tachycardia, left bundle branch block, right bundle branch block, premature atrial contraction, and ST-elevation myocardial infarction. The proposed CNN-BiLSTM model achieves an overall accuracy of 98.1%, sensitivity of 97.6%, specificity of 98.5%, F1-score of 0.979, and AUC-ROC of 0.995 on the held-out test set — substantially outperforming conventional support vector machine (87.3%), random forest (89.6%), standalone 1D-CNN (93.2%), and BiLSTM (94.7%) baselines. Ablation studies confirm the independent contributions of the attention mechanism (+1.8% accuracy) and multi-lead fusion (+1.4% accuracy). The framework demonstrates robust generalisation across age groups, gender, and signal quality categories, with mean inference time of 1.2 seconds per recording on standard hardware — clinically suitable for point-of-care screening applications.
Keywords: ECG classification, cardiac arrhythmia, deep learning, convolutional neural network, bidirectional LSTM, attention mechanism, 12-lead ECG, automated diagnosis, PhysioNet, signal processing
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