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This highly invasive intervention is still linked to a long-term recurrence rate of approximately 35% in permanent AF patients. The aim of this study is to preoperatively predict long-term AF recurrence post-surgery through the analysis of atrial activity (AA) organization from non-invasive electrocardiographic (ECG) recordings. A dataset comprising ECGs from 53 patients with permanent AF who had undergone Cox\u2013Maze concomitant surgery was analyzed. The AA was extracted from the lead V1 of these recordings and then characterized using novel predictors, such as the mean and standard deviation of the relative wavelet energy (RWEm and RWEs) across different scales, and an entropy-based metric that computes the stationary wavelet entropy variability (SWEnV). The individual predictors exhibited limited predictive capabilities to anticipate the outcome of the procedure, with the SWEnV yielding a classification accuracy (Acc) of 68.07%. However, the assessment of the RWEs for the seventh scale (RWEs7), which encompassed frequencies associated with the AA, stood out as the most promising individual predictor, with sensitivity (Se) and specificity (Sp) values of 80.83% and 67.09%, respectively, and an Acc of almost 75%. Diverse multivariate decision tree-based models were constructed for prediction, giving priority to simplicity in the interpretation of the forecasting methodology. In fact, the combination of the SWEnV and RWEs7 consistently outperformed the individual predictors and excelled in predicting post-surgery outcomes one year after the Cox\u2013Maze procedure, with Se, Sp, and Acc values of approximately 80%, thus surpassing the results of previous studies based on anatomical predictors associated with atrial function or clinical data. These findings emphasize the crucial role of preoperative patient-specific ECG signal analysis in tailoring post-surgical care, enhancing clinical decision making, and improving long-term clinical outcomes.<\/jats:p>","DOI":"10.3390\/e26010028","type":"journal-article","created":{"date-parts":[[2023,12,27]],"date-time":"2023-12-27T05:43:15Z","timestamp":1703655795000},"page":"28","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Novel Entropy-Based Metrics for Long-Term Atrial Fibrillation Recurrence Prediction Following Surgical Ablation: Insights from Preoperative Electrocardiographic Analysis"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4492-2045","authenticated-orcid":false,"given":"Pilar","family":"Escribano","sequence":"first","affiliation":[{"name":"Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, 02071 Albacete, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9497-4935","authenticated-orcid":false,"given":"Juan","family":"R\u00f3denas","sequence":"additional","affiliation":[{"name":"Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, 02071 Albacete, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5454-456X","authenticated-orcid":false,"given":"Manuel","family":"Garc\u00eda","sequence":"additional","affiliation":[{"name":"Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, 02071 Albacete, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7560-2781","authenticated-orcid":false,"given":"Fernando","family":"Hornero","sequence":"additional","affiliation":[{"name":"Cardiovascular Surgery Department, Hospital Cl\u00ednico Universitario de Valencia, 46010 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5277-3847","authenticated-orcid":false,"given":"Juan M.","family":"Gracia-Baena","sequence":"additional","affiliation":[{"name":"Cardiovascular Surgery Department, Hospital Cl\u00ednico Universitario de Valencia, 46010 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0942-3638","authenticated-orcid":false,"given":"Ra\u00fal","family":"Alcaraz","sequence":"additional","affiliation":[{"name":"Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, 02071 Albacete, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3364-6380","authenticated-orcid":false,"given":"Jos\u00e9 J.","family":"Rieta","sequence":"additional","affiliation":[{"name":"BioMIT.org, Electronic Engineering Department, Universitat Politecnica de Valencia, 46022 Valencia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1177\/1747493019897870","article-title":"Global epidemiology of atrial fibrillation: An increasing epidemic and public health challenge","volume":"16","author":"Lippi","year":"2021","journal-title":"Int. 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