Abstract :
Fuzzy neural networks (FNNs) have been successfully applied to generate predictive rules for medical or diagnostic data. This brief presents an approach to detect premature ventricular contractions (PVCs) using the neural network with weighted fuzzy membership functions (NEWFMs). The NEWFM classifies normal and PVC beats by the trained bounded sum of weighted fuzzy membership functions (BSWFMs) using wavelet transformed coefficients from the MIT-BIH PVC database. The eight generalized coefficients, locally related to the time signal, are extracted by the nonoverlap area distribution measurement method. The eight generalized coefficients are used for the three PVC data sets with reliable accuracy rates of 99.80%, 99.21%, and 98.78%, respectively, which means that the selected features are less dependent on the data sets. It is shown that the locations of the eight features are not only around the QRS complex that represents ventricular depolarization in the electrocardiogram (ECG) containing a Q wave, an R wave, and an S wave, but also the QR segment from the Q wave to the R wave has more discriminate information than the RS segment from the R wave to the S wave. The BSWFMs of the eight features trained by NEWFM are shown visually, which makes the features explicitly interpretable. Since each BSWFM combines multiple weighted fuzzy membership functions into one using the bounded sum, the eight small-sized BSWFMs can realize real-time PVC detection in a mobile environment.
Keywords :
electrocardiography; feature extraction; fuzzy neural nets; medical signal processing; wavelet transforms; MIT-BIH PVC database; PVC beats; area distribution measurement; electrocardiogram; feature selection; fuzzy neural network system; real-time premature ventricular contraction detection; time signal; ventricular depolarization; wavelet transformed coefficient; weighted fuzzy membership function; Feature selection; fuzzy neural networks (FNNs); premature ventricular contraction (PVC) classification; wavelet transform (WT); weighted fuzzy membership function; Algorithms; Databases, Factual; Electrocardiography; Fuzzy Logic; Heart Ventricles; Humans; Muscle Contraction; Neural Networks (Computer); Pattern Recognition, Automated; Signal Processing, Computer-Assisted; Ventricular Premature Complexes;