{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T06:50:12Z","timestamp":1785912612612,"version":"3.56.0"},"reference-count":29,"publisher":"BMJ","issue":"2","license":[{"start":{"date-parts":[[2021,10,21]],"date-time":"2021-10-21T00:00:00Z","timestamp":1634774400000},"content-version":"unspecified","delay-in-days":20,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Open Heart"],"accepted":{"date-parts":[[2021,10,1]]},"published-print":{"date-parts":[[2021,10]]},"abstract":"<jats:sec>\n                  <jats:title>Objective<\/jats:title>\n                  <jats:p>Incidence and severity of acute myocarditis vary significantly in previous reports and there is a lack of epidemiological studies on the short-term risks of mortality, heart failure and ventricular arrhythmias in patients with acute myocarditis. Therefore, study aims were to examine 90-day risks of mortality, heart failure (HF) and ventricular arrhythmias in patients with acute myocarditis in comparison to age-matched and sex-matched background population controls.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>In this nationwide register-based follow-up study of patients hospitalised with myocarditis between 2002 and 2018 in Denmark, 90-day risks of all-cause mortality, HF, ventricular arrhythmias (ventricular tachycardia, ventricular fibrillation (VF)), cardiac arrest and implantable cardioverter-defibrillator (ICD) implantation were compared with age-matched and sex-matched controls from the background population (1:5 matching). Absolute risks standardised to the age, sex and comorbidity distribution of the entire study population were derived from multivariable Cox regression.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>A total of 2523 patients hospitalised with myocarditis were included. Median age was 48 years (Q1\u2013Q3: 30\u201369) and 67.7% were men. Comorbidity burden was more pronounced among patients with myocarditis relative to controls. Standardised 90-day all-cause mortality risk was 4.9% for patients with acute myocarditis versus 0.3% for controls (p&lt;0.001). Ninety-day standardised risks for other endpoints were 7.5% versus 0.1% for HF, 1.9% versus &lt;0.1% for VF\/VF\/arrest risk and 1.6% versus &lt;0.1% for ICD implantation (all p&lt;0.001).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>In this large nationwide register-based follow-up study, patients hospitalised with myocarditis had significantly higher 90-day risks of all-cause mortality, HF, ventricular arrhythmias, cardiac arrest and ICD implantation compared with background population controls.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1136\/openhrt-2021-001806","type":"journal-article","created":{"date-parts":[[2021,10,21]],"date-time":"2021-10-21T12:43:17Z","timestamp":1634820197000},"page":"e001806","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":27,"title":["Mortality and ventricular arrhythmia after acute myocarditis: a nationwide registry-based follow-up study"],"prefix":"10.1136","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9629-8670","authenticated-orcid":false,"given":"Kristian Hay","family":"Kragholm","sequence":"first","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"},{"name":"Unit of Clinical Biostatistics and Epidemiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filip Lyng","family":"Lindgren","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6365-6638","authenticated-orcid":false,"given":"Tomas","family":"Zaremba","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Phillip","family":"Freeman","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Niels Holmark","family":"Andersen","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sam","family":"Riahi","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manan","family":"Pareek","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Nordsj\u00e6llands Hospital, Hillerod, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars","family":"K\u00f8ber","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Rigshospitalet, Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Torp-Pedersen","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Nordsjaellands Hospital, Hillerod, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"S\u00f8gaard","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Hagendorff","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Leipzig University, Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhupendar","family":"Tayal","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2021,10,21]]},"reference":[{"key":"2025081710131767000_8.2.e001806.1","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.117.310221"},{"key":"2025081710131767000_8.2.e001806.2","doi-asserted-by":"crossref","first-page":"2636","DOI":"10.1093\/eurheartj\/eht210","article-title":"Current state of knowledge on aetiology, diagnosis, management, and therapy of acute myocarditis: a position statement of the European Society of Cardiology Working Group on Myocardial and Pericardial Diseases","volume":"34","author":"Caforio","year":"2013","journal-title":"Europ Heart J Oxford University"},{"key":"2025081710131767000_8.2.e001806.3","doi-asserted-by":"publisher","DOI":"10.1016\/0002-8703(47)90147-6"},{"key":"2025081710131767000_8.2.e001806.4","doi-asserted-by":"crossref","first-page":"1493","DOI":"10.1016\/j.mayocp.2016.07.021","article-title":"Incidence and etiology of sudden cardiac arrest and death in high school athletes in the United States","volume":"91","author":"Harmon","year":"2016","journal-title":"Mayo Clin Proc"},{"key":"2025081710131767000_8.2.e001806.5","doi-asserted-by":"publisher","DOI":"10.1016\/S0008-6363(01)00261-9"},{"key":"2025081710131767000_8.2.e001806.6","article-title":"Increased risk of ventricular tachycardia and cardiovascular death in patients with acute myocarditis during the long-term follow-up","volume":"0","author":"Te ALD","year":"2017","journal-title":"Medicine"},{"key":"2025081710131767000_8.2.e001806.7","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2012.01.007"},{"key":"2025081710131767000_8.2.e001806.8","doi-asserted-by":"crossref","first-page":"1241","DOI":"10.7150\/ijms.20618","article-title":"Heart failure and mortality of adult survivors from acute myocarditis requiring intensive care treatment - a nationwide cohort study","volume":"14","author":"Chang","year":"2017","journal-title":"Int J Med Sci"},{"key":"2025081710131767000_8.2.e001806.9","first-page":"513","article-title":"Diagnostic performance of CMR imaging compared with EMB in patients with suspected acute myocarditis","volume":"5","author":"Lurz","year":"2012","journal-title":"JACC: Cardiovascular Imaging Elsevier"},{"key":"2025081710131767000_8.2.e001806.10","first-page":"390","article-title":"Incidence of myocarditis. A 10-year autopsy study from Malmo, Sweden","volume":"115","author":"Gravanis","year":"1991","journal-title":"Arch Pathol Lab Med"},{"key":"2025081710131767000_8.2.e001806.11","doi-asserted-by":"crossref","first-page":"570","DOI":"10.1093\/aje\/kwk076","article-title":"Incidence of fatal myocarditis: a population-based study in Finland","volume":"165","author":"Kyto","year":"2006","journal-title":"Am J Epidemiol"},{"key":"2025081710131767000_8.2.e001806.12","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/j.cardfail.2017.11.001","article-title":"Electrocardiographic predictors of morbidity and mortality in patients with acute myocarditis: the importance of QRS-T angle","volume":"24","author":"Chen","year":"2018","journal-title":"J Card Fail"},{"key":"2025081710131767000_8.2.e001806.13","doi-asserted-by":"publisher","DOI":"10.1177\/1403494810387965"},{"key":"2025081710131767000_8.2.e001806.14","doi-asserted-by":"publisher","DOI":"10.1177\/1403494811401482"},{"key":"2025081710131767000_8.2.e001806.15","doi-asserted-by":"publisher","DOI":"10.1177\/1403494810394717"},{"key":"2025081710131767000_8.2.e001806.16","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.f7450"},{"key":"2025081710131767000_8.2.e001806.17","doi-asserted-by":"publisher","DOI":"10.1093\/eurheartj\/ehw129"},{"key":"2025081710131767000_8.2.e001806.18","doi-asserted-by":"crossref","DOI":"10.1136\/bmjopen-2016-012832","article-title":"Positive predictive value of cardiovascular diagnoses in the Danish national patient registry: a validation study","volume":"6","author":"Sundb\u00f8ll","year":"2016","journal-title":"BMJ Open"},{"key":"2025081710131767000_8.2.e001806.19","unstructured":"R Core Team . R: a language and environment for statistical computing. R foundation for statistical computing, Vienna, Austria, 2017. Available: https:\/\/www.R-project.org\/"},{"key":"2025081710131767000_8.2.e001806.20","doi-asserted-by":"publisher","DOI":"10.1136\/hrt.85.5.499"},{"key":"2025081710131767000_8.2.e001806.21","first-page":"3","article-title":"Myocarditis. A histopathologic definition and classification","volume":"1","author":"Aretz","year":"1987","journal-title":"Am J Cardiovasc Pathol"},{"key":"2025081710131767000_8.2.e001806.22","doi-asserted-by":"publisher","DOI":"10.1093\/eurheartj\/ehm076"},{"key":"2025081710131767000_8.2.e001806.23","doi-asserted-by":"crossref","DOI":"10.1111\/eci.13444","article-title":"Incidence and outcomes of hospital treated acute myocarditis from 2003 to 2015 in Spain","volume":"51","author":"Ruiz-Ortiz","year":"2021","journal-title":"Eur J Clin Invest"},{"key":"2025081710131767000_8.2.e001806.24","doi-asserted-by":"publisher","DOI":"10.1253\/jcj.65.961"},{"key":"2025081710131767000_8.2.e001806.25","doi-asserted-by":"publisher","DOI":"10.1016\/S0025-6196(12)61286-5"},{"key":"2025081710131767000_8.2.e001806.26","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1161\/01.CIR.75.2.401","article-title":"Interobserver variability in the pathologic interpretation of endomyocardial biopsy results","volume":"75","author":"Shanes","year":"1987","journal-title":"Circulation"},{"key":"2025081710131767000_8.2.e001806.27","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2004.11.069"},{"key":"2025081710131767000_8.2.e001806.28","doi-asserted-by":"crossref","first-page":"1475","DOI":"10.1016\/j.jacc.2009.02.007","article-title":"International consensus group on cardiovascular magnetic resonance in myocarditis. cardiovascular magnetic resonance in myocarditis: a JACC white paper","volume":"17","author":"Friedrich","year":"2009","journal-title":"J Am Coll Cardiol"},{"key":"2025081710131767000_8.2.e001806.29","doi-asserted-by":"crossref","DOI":"10.4414\/smw.2019.20098","article-title":"Systematic use of cardiac magnetic resonance imaging in MINOCA led to a five-fold increase in the detection rate of myocarditis: a retrospective study","volume":"149","author":"Heidecker","year":"2019","journal-title":"Swiss Med Wkly"}],"container-title":["Open Heart"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/openhrt-2021-001806","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,17]],"date-time":"2025-08-17T17:13:24Z","timestamp":1755450804000},"score":1,"resource":{"primary":{"URL":"https:\/\/openheart.bmj.com\/lookup\/doi\/10.1136\/openhrt-2021-001806"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10]]},"references-count":29,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2021,10,21]]},"published-print":{"date-parts":[[2021,10]]}},"alternative-id":["10.1136\/openhrt-2021-001806"],"URL":"https:\/\/doi.org\/10.1136\/openhrt-2021-001806","relation":{},"ISSN":["2053-3624"],"issn-type":[{"value":"2053-3624","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,10]]}}}