Simple, efficient, and generalized ECG signal quality assessment method for telemedicine applications

Abstract

Electrocardiogram (ECG) signals recorded by paramedics in an unsupervised environment are prone to errors and noise due to factors such as electrode misplacements and daily activities during prolonged monitoring. Signal Quality Assessment (SQA) systems can prevent false diagnoses by automated arrhythmia detection systems and reduce the workload of cardiologists. However, current SQA methods are quite complex and/or exhibit poor performances in presence of certain arrhythmias. This study proposed a novel SQA method consisting of three main steps: (1) feasibility conditions check, (2) average beat correlation algorithm, and (3) beat clustering algorithm. The system uses empirical probability functions to automatically adapt the quality score according to the presence of pathological beats and/or noises. We evaluated the proposed method on three datasets and considered both three-quality classes ('Bad', 'HR' and 'Diagnostic') and two-quality classes ('Acceptable' and 'Unacceptable'). For the three-class classification, we obtained an average accuracy of 81.42 % while for the two-class, our algorithm achieved an average sensitivity of 94.59 %, a specificity of 98.38 %, and an accuracy of 97.10 %. The results show that our method achieves high accuracy, specificity and generalizability, outperforming the simple heuristic rule, machine learning, and deep learning methods. Additionally, the algorithm requires less computational time, making it suitable for telemedicine applications.