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Artificial Intelligence in Health                                     ML models for heartbeat classification



            and smart healthcare systems. An EKG is a  graphical   expertise  and recording  quality of  clinicians,  yielding
            representation of the heart’s electrical activity over time,   high diagnostic accuracy but remaining prone to human
            obtained by affixing electrodes on the skin surface. The   errors.  ML models, trained on large annotated datasets
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            human body generates various biomedical signals, and   and enhanced with preprocessing techniques such as
            electrocardiography sensors record the heart’s electrical   Fourier transform (FT) and Gaussian noise injection, can
            activity by generating three-lead EKGs for heart monitoring   achieve similar or even superior accuracy at 90 – 99% in
            and surface electromyography for muscle contractions.    detecting cardiac abnormalities. 13
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            ECGs are crucial for diagnosing cardiovascular conditions   This study integrates the use of the FT and Gaussian
            and aid in the early detection of heart attacks and treatment   noise injection techniques to enhance the capability of ML
            to prevent them.  However, identifying and classifying   models trained and tested on the datasets provided by the
                          2
            arrhythmias are challenging due to the requirement of   University of Chinese Academy of Sciences, which will
            extensive  data  analysis,  potential human  errors,  and   be presented in subsequent sections. The FT technique is
            signal variability. Furthermore, developing an automated   essential for preprocessing heartbeat signals in ML models,
            detection system is difficult due to data complexity and   converting time-domain signals into frequency-domain
            noise; however, ECGs are indispensable for diagnosing   ones to filter noise and improve signal quality, thereby
            heart diseases. Anomalous deviations from a typical   enhancing  model  performance  to a  level  equal to  or
            ECG pattern are observed in various cardiac disorders,   greater than that obtained with the 12-lead ECG analysis.
            including irregular heart rhythms such as atrial fibrillation   Unlike state-of-the-art algorithms such as convolutional
            and ventricular tachycardia;  diminished blood flow   neural networks (CNNs), which filter noise implicitly, the
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            through the coronary arteries, which is observed in cases   FT  technique  explicitly  reduces  computational  demands
            such as myocardial ischemia and myocardial infarction;   and improves training efficiency. Traditional ML models
            and disruptions in the electrolyte balance such as in   benefit greatly from noise reduction, leading to improved
            hypokalemia and hyperkalemia. 4                    classification accuracy. In addition, Gaussian noise
              Since the 20  century, ECG analysis has been vital for   injection adds controlled noise during training, enhancing
                        th
            diagnosing cardiovascular diseases by monitoring the   model robustness and generalization capability, which
            heart’s electrical activity. The conventional 12-lead ECG,   is particularly useful for heartbeat classification, thereby
            recorded  by  affixing  electrodes to  the  chest  and limbs,   improving performance on unseen data and reducing the
            is  crucial  for  detecting  arrhythmias.  Early  diagnosis  is   risk of overfitting. In practical applications, these methods
            essential for effective treatment, sometimes requiring   enhance accuracy and reliability, making them suitable for
            over 24  h of continuous monitoring.  Advances in the   applications in clinical settings and resource-constrained
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            digital industry have improved devices, data acquisition   environments such as wearable devices and mobile health
            techniques, and computer-assisted diagnostics. Although   applications.
            ECGs are widely used by cardiologists to monitor heart   This study aims to classify heartbeats  using data
            health, a manual analysis of the associated signals is   from heartbeat sequences recorded by patient heartbeat
            time-consuming and error-prone. Therefore, an accurate   signal sensors. The key contributions of this study are
            diagnosis of cardiovascular conditions is crucial as these   summarized as follows:
            conditions contribute to approximately one-third of global   •   Introduce the innovative application of the FT technique
            mortality. The  prevalence  of irregular  heart rhythms   to preprocess ECG signals by converting time-domain
            highlights the need for precise and cost-effective methods   data into frequency-domain representations, allowing
            to diagnose arrhythmic heartbeats. 6                  for the effective noise reduction and enhancement of

              The classification of ECG signals is challenging due   signal quality.
            to individual variability and the lack of standardization   •   Employ Gaussian noise injection as a novel approach
            in feature extraction, often leading to low diagnostic   to simulate real-world noise conditions by training
            accuracy.  To address the limitations of manual       datasets to be more robust against various types
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            ECG signal analysis, numerous studies have applied    of noise and artifacts commonly observed in ECG
            machine learning (ML) techniques for accurate anomaly   signals.
            detection. 10-12  Traditional methods for this analysis involve   •   Conduct a comparative analysis of various ML models
            signal preprocessing, handcrafted feature extraction, and   by assessing their performance on the preprocessed
            the use of ML and deep learning algorithms. However,   ECG  data.  Emphasize  the  influence  of  the  FT  and
            deep learning requires extensive datasets due to the large   Gaussian noise integration techniques on key metrics
            number  of  the associated parameters.  The traditional   such as accuracy, precision, recall, and F1 score for
            12-lead ECG analysis in clinical settings depends on the   each algorithm.


            Volume 1 Issue 4 (2024)                         62                               doi: 10.36922/aih.3543
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