{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T22:08:42Z","timestamp":1785017322037,"version":"3.55.0"},"reference-count":12,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,6,1]],"date-time":"2021-06-01T00:00:00Z","timestamp":1622505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinics and Practice"],"abstract":"<jats:p>This is a retrospective case series of two patients with laboratory-confirmed coronavirus 2 (SARS-CoV-2) infection, presented to the University of Arkansas for Medical Sciences in January 2021. Medical records of these patients were reviewed using the EPIC electronic health record system. Clinical, laboratory, and treatment data were reviewed against periods of bradycardia in each patient. Both of the patients presented with dizziness and presyncope related to sinus bradycardia in which they received treatment with 1 mg of IV atropine and theophylline 200 mg orally. We share these two cases of theophylline treatment in COVID-19 induced sinus bradycardia. The first patient was a 39-year-old female, with a past medical history of polycystic ovarian syndrome, who presented to the emergency department with lightheadedness and dizziness. Two weeks prior to her presentation, she was tested positive for COVID-19 infection that was treated with azithromycin, dexamethasone and aspirin. Upon presentation, her ECG showed sinus bradycardia at a rate of 48 bpm. The second patient, a 21-year-old female with no significant past medical history, presented with presyncope. Three weeks prior to her presentation, she tested positive for COVID-19 infection that was treated symptomatically at her home. Upon presentation, her ECG showed junctional rhythm at a heart rate of 51 bpm.<\/jats:p>","DOI":"10.3390\/clinpract11020047","type":"journal-article","created":{"date-parts":[[2021,6,1]],"date-time":"2021-06-01T15:58:44Z","timestamp":1622563124000},"page":"332-336","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Theophylline in Treatment of COVID-19 Induced Sinus Bradycardia"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1234-9133","authenticated-orcid":false,"given":"Khalid","family":"Sawalha","sequence":"first","affiliation":[{"name":"Internal Medicine Division, White River Health System, Batesville, AR 72501, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3387-7194","authenticated-orcid":false,"given":"Fuad J.","family":"Habash","sequence":"additional","affiliation":[{"name":"Cardiology Division, University of Arkansas for Medical Sciences, Little Rock, AR 72501, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Srikanth","family":"Vallurupalli","sequence":"additional","affiliation":[{"name":"Cardiology Division, University of Arkansas for Medical Sciences, Little Rock, AR 72501, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hakan","family":"Paydak","sequence":"additional","affiliation":[{"name":"Electrophysiology Division, University of Arkansas for Medical Sciences, Little Rock, AR 72501, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1119","DOI":"10.1016\/0002-8703(92)91012-P","article-title":"Normal sinus heart rate: Sinus tachycardia and sinus bradycardia redefined","volume":"124","author":"Spodick","year":"1992","journal-title":"Am. 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