{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T15:52:03Z","timestamp":1777737123241,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,18]],"date-time":"2021-01-18T00:00:00Z","timestamp":1610928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Science and Technology Service Network Initiative of the Chinese Academy of Sciences","award":["KFJ-STS-ZDTP-079"],"award-info":[{"award-number":["KFJ-STS-ZDTP-079"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Early detection of arrhythmia and effective treatment can prevent deaths caused by cardiovascular disease (CVD). In clinical practice, the diagnosis is made by checking the electrocardiogram (ECG) beat-by-beat, but this is usually time-consuming and laborious. In the paper, we propose an automatic ECG classification method based on Continuous Wavelet Transform (CWT) and Convolutional Neural Network (CNN). CWT is used to decompose ECG signals to obtain different time-frequency components, and CNN is used to extract features from the 2D-scalogram composed of the above time-frequency components. Considering the surrounding R peak interval (also called RR interval) is also useful for the diagnosis of arrhythmia, four RR interval features are extracted and combined with the CNN features to input into a fully connected layer for ECG classification. By testing in the MIT-BIH arrhythmia database, our method achieves an overall performance of 70.75%, 67.47%, 68.76%, and 98.74% for positive predictive value, sensitivity, F1-score, and accuracy, respectively. Compared with existing methods, the overall F1-score of our method is increased by 4.75~16.85%. Because our method is simple and highly accurate, it can potentially be used as a clinical auxiliary diagnostic tool.<\/jats:p>","DOI":"10.3390\/e23010119","type":"journal-article","created":{"date-parts":[[2021,1,19]],"date-time":"2021-01-19T04:55:31Z","timestamp":1611032131000},"page":"119","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":254,"title":["Automatic ECG Classification Using Continuous Wavelet Transform and Convolutional Neural Network"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2926-3977","authenticated-orcid":false,"given":"Tao","family":"Wang","sequence":"first","affiliation":[{"name":"School of Computer and Information, Hefei University of Technology, Hefei 230009, China"}]},{"given":"Changhua","family":"Lu","sequence":"additional","affiliation":[{"name":"School of Computer and Information, Hefei University of Technology, Hefei 230009, China"}]},{"given":"Yining","family":"Sun","sequence":"additional","affiliation":[{"name":"Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031, China"}]},{"given":"Mei","family":"Yang","sequence":"additional","affiliation":[{"name":"Beijing Huaru Technology Co., Ltd., Hefei Branch, Hefei 230088, China"}]},{"given":"Chun","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Automation, Hefei University of Technology, Hefei 230009, China"}]},{"given":"Chunsheng","family":"Ou","sequence":"additional","affiliation":[{"name":"School of Computer and Information, Hefei University of Technology, Hefei 230009, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"446","DOI":"10.1016\/j.future.2018.03.057","article-title":"A deep learning approach for ECG-based heartbeat classification for arrhythmia detection","volume":"86","author":"Sannino","year":"2018","journal-title":"Future Gener. 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