{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:55:37Z","timestamp":1787028937040,"version":"build-2736575974"},"reference-count":32,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T00:00:00Z","timestamp":1768262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Monday syndrome refers to a psychosomatic stress response occurring at the beginning of the work week and has been implicated in triggering acute cardiovascular events. This study aimed to evaluate the association between Monday syndrome and the incidence of cardiovascular emergencies. Materials and Methods: Between June 2024 and June 2025, a total of 500 patients aged 18\u201365 years who presented with acute cardiovascular events at two centers were retrospectively analyzed. Diagnoses included STEMI, NSTEMI, unstable angina, ventricular tachycardia\/fibrillation, and hypertensive emergency. The distribution of events by weekday and hour was examined. Poisson regression was used to assess the effect of Mondays on event incidence. Results: Of 500 patients (mean age 49.1 \u00b1 9.7 years, 50.4% male), the most common diagnoses were STEMI (31.8%) and NSTEMI (27.4%). The incidence of cardiovascular events was highest on Mondays (19.6%) and lowest on Sundays (10.6%). The early-morning period (06:00\u201310:00) showed the most significant clustering of events (p &lt; 0.001). Systolic blood pressure (145 \u00b1 18 vs. 139 \u00b1 17 mmHg, p = 0.008) and heart rate (87 \u00b1 12 vs. 82 \u00b1 13 bpm, p = 0.01) were significantly higher on Mondays. Monday presentation was associated with a 23% higher event rate (incidence rate ratio [IRR] 1.23, 95% CI 1.10\u20131.38, p = 0.002). Conclusions: Monday syndrome is associated with a significant increase in the incidence of cardiovascular emergencies, especially in the early-morning hours. Increased sympathetic tone, hormonal activation, and psychosocial stress are possible contributors.<\/jats:p>","DOI":"10.3390\/medicina62010160","type":"journal-article","created":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T15:52:57Z","timestamp":1768319577000},"page":"160","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Monday Effect: Weekly and Circadian Patterns in Acute Cardiovascular Emergencies Monday Effect in Cardiovascular Emergencies"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0114-7448","authenticated-orcid":false,"given":"Gamze Yeter","family":"Arslan","sequence":"first","affiliation":[{"name":"Department of Cardiology, Kepez State Hospital, 07320 Antalya, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6034-9413","authenticated-orcid":false,"given":"Erkan","family":"Baysal","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Gazi Ya\u015fargil Training and Research Hospital, 21080 Diyarbak\u0131r, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1016\/0002-9149(87)91027-7","article-title":"Circadian variation in the incidence of sudden cardiac death in the Framingham Heart Study population","volume":"60","author":"Willich","year":"1987","journal-title":"Am. J. Cardiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1315","DOI":"10.1056\/NEJM198511213132103","article-title":"Circadian variation in the frequency of onset of acute myocardial infarction","volume":"313","author":"Muller","year":"1985","journal-title":"N. Engl. J. Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1198","DOI":"10.1016\/S0002-9149(96)00595-4","article-title":"Chronobiology of acute myocardial infarction: Cardiac Arrhythmia Suppression Trial (CAST) experience","volume":"78","author":"Peters","year":"1996","journal-title":"Am. J. Cardiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1161\/01.CIR.75.2.395","article-title":"Circadian variation of transient myocardial ischemia","volume":"75","author":"Rocco","year":"1987","journal-title":"Circulation"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1161\/CIRCRESAHA.119.313349","article-title":"Chronobiological Influence Over Cardiovascular Function: The Good, the Bad, and the Ugly","volume":"126","author":"Rana","year":"2020","journal-title":"Circ. Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"765","DOI":"10.1161\/HYPERTENSIONAHA.110.157149","article-title":"Morning surge in blood pressure and cardiovascular risk: Evidence and perspectives","volume":"56","author":"Kario","year":"2010","journal-title":"Hypertension"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1136\/bmj.320.7229.218","article-title":"\u201cI don\u2019t like Mondays\u201d\u2014day of the week of coronary heart disease deaths in Scotland: Study of routinely collected data","volume":"320","author":"Evans","year":"2000","journal-title":"BMJ"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"654","DOI":"10.1038\/nrcardio.2017.76","article-title":"Seasonal variations in cardiovascular disease","volume":"14","author":"Stewart","year":"2017","journal-title":"Nat. Rev. Cardiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1161\/01.CIR.80.2.267","article-title":"Differing circadian patterns of symptom onset in subgroups of patients with acute myocardial infarction","volume":"80","author":"Hjalmarson","year":"1989","journal-title":"Circulation"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"980","DOI":"10.1161\/CIRCRESAHA.110.233668","article-title":"Existence of an endogenous circadian blood pressure rhythm in humans","volume":"108","author":"Shea","year":"2011","journal-title":"Circulation Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1177\/0748730415575246","article-title":"Influence of the cardiomyocyte circadian clock on cardiac physiology and pathophysiology","volume":"30","author":"Martino","year":"2015","journal-title":"J. Biol. Rhythm."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"767","DOI":"10.1016\/j.tem.2019.07.008","article-title":"Impact of Circadian Disruption on Cardiovascular Function and Disease","volume":"30","author":"Chellappa","year":"2019","journal-title":"Trends Endocrinol. Metab."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/j.smrv.2011.04.003","article-title":"Circadian rhythms and cardiovascular health","volume":"16","author":"Portaluppi","year":"2012","journal-title":"Sleep Med. Rev."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2368","DOI":"10.1056\/NEJMra060433","article-title":"Ambulatory blood-pressure monitoring","volume":"354","author":"Pickering","year":"2006","journal-title":"N. Engl. J. Med."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1097\/MBP.0000000000000301","article-title":"Blood pressure monitoring: Theory and practice","volume":"23","author":"Stergiou","year":"2018","journal-title":"Blood Press. Monit."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"976","DOI":"10.1161\/CIRCRESAHA.116.303604","article-title":"The sympathetic nervous system alterations in human hypertension","volume":"116","author":"Grassi","year":"2015","journal-title":"Circ. Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"992","DOI":"10.1161\/01.STR.29.5.992","article-title":"Circadian variation in the timing of stroke onset: A meta-analysis","volume":"29","author":"Elliott","year":"1998","journal-title":"Stroke"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2073","DOI":"10.1161\/CIRCULATIONAHA.111.025858","article-title":"Insomnia and the risk of acute myocardial infarction","volume":"124","author":"Laugsand","year":"2011","journal-title":"Circulation"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1484","DOI":"10.1093\/eurheartj\/ehr007","article-title":"Sleep duration predicts cardiovascular outcomes","volume":"32","author":"Cappuccio","year":"2011","journal-title":"Eur. Heart J."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/j.neubiorev.2016.07.004","article-title":"Sleep, sleep deprivation, autonomic nervous system and cardiovascular diseases","volume":"74","author":"Tobaldini","year":"2017","journal-title":"Neurosci. Biobehav. Rev."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Matteucci, A., Bonanni, M., Centioni, M., Zanin, F., Geuna, F., Massaro, G., and Sangiorgi, G. (2021). Home Management of Heart Failure and Arrhythmias in Patients with Cardiac Devices during Pandemic. J. Clin. Med., 10.","DOI":"10.3390\/jcm10081618"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1804","DOI":"10.1161\/CIRCRESAHA.114.302524","article-title":"The autonomic nervous system and hypertension","volume":"114","author":"Mancia","year":"2014","journal-title":"Circ. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/j.neubiorev.2016.10.011","article-title":"Mental stress and human cardiovascular disease","volume":"74","author":"Esler","year":"2017","journal-title":"Neurosci. Biobehav. Rev."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"360","DOI":"10.1038\/nrcardio.2012.45","article-title":"Stress and cardiovascular disease","volume":"9","author":"Steptoe","year":"2012","journal-title":"Nat. Rev. Cardiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"953","DOI":"10.1016\/S0140-6736(04)17019-0","article-title":"Association of psychosocial risk factors with myocardial infarction","volume":"364","author":"Rosengren","year":"2004","journal-title":"Lancet"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"690","DOI":"10.1016\/S0195-668X(02)00615-2","article-title":"Systematic review of mental stress-induced myocardial ischemia","volume":"24","author":"Strike","year":"2003","journal-title":"Eur. Heart J."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"668","DOI":"10.1016\/j.sleep.2006.11.011","article-title":"Role of sleep-wake cycle on blood pressure circadian rhythms and hypertension","volume":"8","author":"Smolensky","year":"2007","journal-title":"Sleep Med."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.pcad.2023.03.003","article-title":"The polypill strategy in cardiovascular disease prevention: It\u2019s time for its implementation","volume":"79","author":"Aquilani","year":"2023","journal-title":"Prog. Cardiovasc. Dis."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Matteucci, A., Pandozi, C., Bonanni, M., Mariani, M.V., Sgarra, L., Nesti, L., Pierucci, N., La Fazia, V.M., Lavalle, C., and Nardi, F. (2025). Impact of empagliflozin and dapagliflozin on sudden cardiac death: A systematic review and meta-analysis of adjudicated randomized evidence. Heart Rhythm.","DOI":"10.1016\/j.hrthm.2025.09.023"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"570","DOI":"10.1016\/S0140-6736(08)61237-4","article-title":"Acute myocardial infarction","volume":"372","author":"White","year":"2008","journal-title":"Lancet"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1093\/eurheartj\/ehx393","article-title":"2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC)","volume":"39","author":"Ibanez","year":"2018","journal-title":"Eur. Heart J."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1093\/eurheartj\/ehy462","article-title":"Fourth universal definition of myocardial infarction (2018)","volume":"40","author":"Thygesen","year":"2018","journal-title":"Eur. Heart J."}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/1\/160\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T16:16:38Z","timestamp":1768320998000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/1\/160"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,13]]},"references-count":32,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,1]]}},"alternative-id":["medicina62010160"],"URL":"https:\/\/doi.org\/10.3390\/medicina62010160","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,13]]}}}