Scalogram-Based Binary Fetal Arrhythmia Classification Using ML and DL

Öz

Objectives: Fetal electrocardiography (FECG) is a valuable tool for assessing fetal health and identifying cardiac rhythm abnormalities. This study aimed to determine the convolutional neural network (CNN)-based deep learning (DL) model that provides the highest performance for binary classification of fetal arrhythmia and normal rhythm (ARR vs NR) in FECG signals. Methods: FECG signals were converted to time-frequency images using the Continuous Wave Transform (CWT), and these images were used as input to DL-based CNN architectures such as AlexNet, GoogleNet, and ResNet50. The effect of data length was investigated to achieve high accuracy with transfer learning. In addition, these DL models were compared with traditional machine learning methods. Results: Among the evaluated DL models, AlexNet achieved the highest performance on the 10-second segments. It outperformed the traditional machine learning approaches across all evaluated metrics. Among the conventional methods, the Trilayered Neural Network showed the best performance, with an accuracy of 87.50%. Conclusions: The findings suggest that scalogram-based CNN models have strong potential for classifying binary fetal arrhythmias from FECG signals. In particular, the AlexNet model showed promising performance under the experimental conditions of this study. However, the results should be interpreted with caution due to the limited dataset size, and further validation on larger, independent datasets is needed.

Anahtar Kelimeler

• Arrhythmia detection
• automated fetal monitoring
• convolutional neural networks
• continuous wavelet transform
• deep learning
• fetal electrocardiogram
• machine learning.

Skalogram Tabanlı Makine Öğrenmesi ve Derin Öğrenme Teknikleri Kullanılarak Fetal Aritmi Tespiti ve Sınıflandırılması

Öz

Özet—Amaçlar: Fetal elektrokardiyografi (FECG), fetal sağlığın değerlendirilmesi ve kardiyak anomalilerin tespit edilmesi için değerli bir araçtır. Bu çalışmanın amacı, FECG sinyallerinde aritmi tespiti ve sınıflandırması için en yüksek performansı sağlayacak Evrişimsel Sinir Ağı (CNN) tabanlı derin öğrenme (DL) algoritmasını belirlemektir. Yöntemler: FECG sinyalleri Sürekli Dalgacık Dönüşümü (Continuous Wavelet Transform, CWT) yöntemi ile zaman-frekans görüntülerine dönüştürülmüş ve bu görüntüler AlexNet, GoogLeNet ve ResNet50 gibi DL tabanlı CNN mimarilerinde giriş verisi olarak kullanılmıştır. Veri uzunluğunun etkisi incelenmiş ve transfer öğrenme ile yüksek doğruluk elde edilmesi amaçlanmıştır. Buna ek olarak, bu DL modelleri geleneksel makine öğrenmesi yöntemleri ile karşılaştırılmıştır. Bulgular: AlexNet mimarisi, doğruluk, duyarlılık, özgüllük ve kesinlik değerlerinde en yüksek performansı sağlayarak %100 başarı oranına ulaşmış ve tüm performans metriklerinde geleneksel makine öğrenmesi yaklaşımlarından daha iyi sonuçlar elde etmiştir. Geleneksel yöntemler arasında üç katmanlı Yapay Sinir Ağı, %87,50 doğruluk oranı ile en iyi performansı göstermiştir. Sonuçlar: AlexNet’in performansı, CNN’lerin FECG sinyallerinden fetal kalp anomalilerini doğru bir şekilde tespit etme konusunda büyük bir potansiyele sahip olduğunu göstermektedir. Transfer öğrenme ile elde edilen başarılı sonuçlar, derin öğrenme yöntemlerinin fetal sağlık değerlendirmelerindeki etkinliğini ortaya koymaktadır.

Anahtar Kelimeler

• Aritmi tespiti
• otomatik fetal izleme
• evrişimsel sinir ağları
• sürekli dalgacık dönüşümü
• derin öğrenme
• fetal elektrokardiyogram

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