{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T03:57:50Z","timestamp":1777348670571,"version":"3.51.4"},"reference-count":30,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T00:00:00Z","timestamp":1710288000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000274","name":"British Heart Foundation","doi-asserted-by":"publisher","award":["CS\/18\/3\/34063"],"award-info":[{"award-number":["CS\/18\/3\/34063"]}],"id":[{"id":"10.13039\/501100000274","id-type":"DOI","asserted-by":"publisher"}]},{"name":"UK National Institute for Health Research\u2019s Comprehensive Biomedical Research Centre at University College London Hospitals"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>Atrial Fibrillation After Cardiac Surgery (AFACS) occurs in about one in three patients following Coronary Artery Bypass Grafting (CABG). It is associated with increased short- and long-term morbidity, mortality and costs. To reduce AFACS incidence, efforts are often made to maintain serum potassium in the high-normal range (\u2265 4.5mEq\/L). However, there is no evidence that this strategy is efficacious. Furthermore, the approach is costly, often unpleasant for patients, and risks causing harm. We describe the protocol of a planned randomized non-inferiority trial to investigate the impact of intervening to maintain serum potassium \u2265 3.6 mEq\/L vs \u2265 4.5 mEq\/L on incidence of new-onset AFACS after isolated elective CABG.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>Patients undergoing isolated CABG at sites in the UK and Germany will be recruited, randomized 1:1 and stratified by site to protocols maintaining serum potassium at either \u2265 3.6 mEq\/L or \u2265 4.5 mEq\/L. Participants will not be blind to treatment allocation. The primary endpoint is AFACS, defined as an episode of atrial fibrillation, flutter or tachycardia lasting \u2265 30 seconds until hour 120 after surgery, which is both clinically detected and electrocardiographically confirmed.<\/jats:p>\n<jats:p>Assuming a 35% incidence of AFACS in the \u2018tight control group\u2019, and allowing for a 10% loss to follow-up, 1684 participants are required to provide 90% certainty that the upper limit of a one-sided 97.5% confidence interval (CI) will exclude a &gt; 10% difference in favour of tight potassium control. Secondary endpoints include mortality, use of hospital resources and incidence of dysrhythmias not meeting the primary endpoint (detected using continuous heart rhythm monitoring).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Discussion<\/jats:title>\n<jats:p>The Tight K Trial will assess whether a protocol to maintain serum potassium \u2265 3.6 mEq\/L is non inferior to maintaining serum potassium \u2265 4.5 mEq\/L in preventing new-onset AFACS after isolated CABG.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Trial registration<\/jats:title>\n<jats:p>ClinicalTrials.gov Identifier: <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/clinicaltrials.gov\/study\/NCT04053816\" xlink:type=\"simple\">NCT04053816<\/jats:ext-link>. Registered on 13 August 2019. Last update 7 January 2021.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0296525","type":"journal-article","created":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T17:26:33Z","timestamp":1710350793000},"page":"e0296525","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":3,"title":["Impact of maintaining serum potassium concentration \u2265 3.6mEq\/L versus \u2265 4.5mEq\/L for 120 hours after isolated coronary artery bypass graft surgery on incidence of new onset atrial fibrillation: Protocol for a randomized non-inferiority trial"],"prefix":"10.1371","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4269-3848","authenticated-orcid":true,"given":"Niall 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E.","family":"Montgomery","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diana","family":"Elbourne","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7024-2337","authenticated-orcid":true,"given":"Benjamin","family":"O\u2019Brien","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2024,3,13]]},"reference":[{"key":"pone.0296525.ref001","doi-asserted-by":"crossref","first-page":"1720","DOI":"10.1001\/jama.291.14.1720","article-title":"A multicenter risk index for atrial fibrillation after cardiac surgery","volume":"291","author":"JP Mathew","year":"2004","journal-title":"JAMA"},{"key":"pone.0296525.ref002","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1186\/1749-8090-7-87","article-title":"Atrial fibrillation following cardiac surgery: risk 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Developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology (ESC) and the European Cardiac Arrhythmia Society (ECAS); and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). 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