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Artificial Intelligence in Health                                   A fuzzy system for heartbeat classification



            condition detection, a variable threshold is applied to the   time-frequency plane to display the locations of different
            adaptive neuro-fuzzy inference system (ANFIS) output,   peaks, the TERMA algorithm designates specific areas of
            and the parameters are adjusted accurately. The proposed   interest to locate the desired peak.  In the study, a DL-based
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            system has three parts. First, the input ECGs undergoes   system is presented; using convolutional neural networks
            preprocessing to eliminate noise. In the second step, feature   (CNNs) for ECG classification with the PhysioNet MIT-
            extraction prepares the inputs for the ANFIS, while heart   BIH Arrhythmia database.  The suggested system  uses a
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            conditions are labeled using the subtractive clustering   1-D convolutional deep residual neural network (ResNet)
            method to train the ANFIS.                         model, which uses the input heartbeats directly to extract
              ANFIS is a binary classifier, so to classify six classes; six   features. To handle the class imbalance in the training
            separate ANFIS systems are required. This mechanism, as   dataset and effectively classify five heartbeat types in the
            the third stage, can be known as a multi-binary classifier.   test dataset, the synthetic minority oversampling technique
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            Across this process, classification is achieved; however, to   was employed.  In addition, raw ECG recordings are
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            enhance accuracy, six thresholds are applied to the output   classified using deep CNNs.  However, these CNNs require
            of each ANFIS. By tuning the threshold values, a variable-  extensive annotated samples for effective training, which
            threshold system is created that yields optimal results. The   can be costly to obtain. To mitigate this issue, transfer
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            categorization of ECG arrhythmias is crucial for quick   learning is utilized.  Using the largest available collection
            identification and diagnosis of cardiovascular disorders.   of continuous raw ECG signals, the first CNNs were pre-
            A more accurate diagnosis allows for timely and suitable   trained. Next, the networks were refined for the most
            interventions when needed. These diagnostic techniques   common cardiac arrhythmia and atrial fibrillation using a
            can be integrated into electronic devices used by individuals   small data set. An artificial NN approach was presented for
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            with cardiac problems, and in the event of an emergency,   the automatic identification and categorization of ECG.
            appropriate alerts can be delivered to medical facilities,   To thoroughly mine the hierarchical and time-sensitive
            such as hospitals or physicians. In addition, hospitals   features of ECG data, a dense heart rhythm network has
            can regularly employ these methods to diagnose cardiac   been developed that combines a 24-layer deep CNN and
            problems early, reducing the need for human intervention.   bidirectional long short-term memory. The original ECG
            With the use of ECG classification approaches, individuals   is filtered using a combination of wavelet transform and
            with established cardiac diseases can be monitored   median filtering to remove the influence of noise on the
            continuously. As the disease progresses or as a patient   signal. In addition, three different sizes of convolution
            responds to treatment, changes in the ECG pattern over   kernels (32, 64, and 128) are used to mine the detailed
            time can help doctors make well-informed judgments   features from the ECG signal.
            about modifying treatment plans. With significant    The symlet wavelet transform was presented to detect
            accuracy and precision, the suggested method can make   the QRS complex and reduce the error.  Using values of RR
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            a significant contribution to this field by classifying six   intervals, amplitude, and Hjorth parameters, some features
            classes of heart diseases. Since biomedical signals are very   of the ECG were extracted for heartbeat classification.
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            sensitive, even a small improvement in speed, accuracy,   Techniques, including variation mode decomposition,
            and precision can greatly impact individuals’ health and   phase space reconstruction, euclidean distance, and
            well-being. Related works are explored in Section 2, while   Shannon energy envelope were employed to detect
            Section 3 discusses the data and methods employed in this   myocardial dysfunction.  The Hilbert-Huang transform was
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            research. The results are discussed in Section 4, and the   used for feature selection, which includes a set of essential
            conclusion is provided in Section 5.               features.  The ANFIS employed Lyapunov exponents for
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                                                               the ECG classification.  A reliable beat classification was
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            2. Related works                                   performed using the wavelet transform and principal
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            Researchers aim to achieve accurate and high-speed   component analysis-independent  component  analysis.
            classification while keeping computational costs low. Robust   An extreme learning machine was applied to the MIT/
            automated  diagnostic  approaches require preprocessing   BIH database, and feature selection was performed using
            of  the  ECG,  enhancing  the  signal,  extracting  features,   the variances  of the wavelet transform and parameters
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            and classifying the data. Different techniques have been   of the autoregressive model.  Furthermore, the ECG
            explored in the literature for detecting diseases through   classification was done by an automatic, reliable, two-stage
            ECG analysis. To enhance ECG analysis, an algorithm is   hybrid hierarchical approach.  The ANFIS, along with
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            put forth that makes use of the fractional Fourier transform   a fuzzy rule-based model classifier, was used to identify
            (FrFT) and two-event-related moving averages (TERMA)   premature ventricular contraction (PVC) beats with a high
            algorithms. While the FrFT rotates ECG signals in the   readability-accuracy trade-off. 13


            Volume 1 Issue 4 (2024)                         45                               doi: 10.36922/aih.3367
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