Editing Myocarditis (section)

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{{Short description|Inflammation of the heart muscle}}
{{Infobox medical condition
| name            = Myocarditis
| image           = Viral myocarditis (1).JPG
| caption         = A [[microscope]] image of myocarditis at [[autopsy]] in a person with acute onset of heart failure. The black dots are primarily [[lymphocyte]]s infiltrating the myocardium.
| field           = [[Infectious disease (medical specialty)|Infectious disease]], [[cardiology]]
| synonyms        = Inflammatory cardiomyopathy (infectious)
| symptoms        = [[Shortness of breath]], [[chest pain]], decreased ability to exercise, [[irregular heartbeat]]<ref name=NEJM2009/>
| complications   = [[Heart failure]] due to [[dilated cardiomyopathy]], [[cardiac arrest]]<ref name=NEJM2009/>
| onset           =
| duration        = Hours to months<ref name=NEJM2009/>
| types           =
| causes          = Usually [[viral infection]], also [[bacterial infections]], certain medications, [[autoimmune disorders]]<ref name=NEJM2009/><ref name=Kin2012/>
| risks           =
| diagnosis       = [[Electrocardiogram]], blood [[troponin]], [[cardiac magnetic resonance imaging|heart MRI]], heart biopsy<ref name=NEJM2009/><ref name=Kin2012/>
| differential    =
| prevention      =
| treatment       = Medications, [[implantable cardiac defibrillator]], [[heart transplant]]<ref name=NEJM2009/><ref name=Kin2012/>
| medication      = [[ACE inhibitors]], [[beta blockers]], [[diuretics]], [[corticosteroids]], [[intravenous immunoglobulin]]<ref name=NEJM2009/><ref name=Kin2012/>
| prognosis       = Variable<ref>{{Cite book |url=https://books.google.com/books?id=eRMTeCwrkhcC&pg=PA181 |title=Netter's Cardiology E-Book |vauthors=Stouffer G, Runge MS, Patterson C |date=2010 |publisher=Elsevier Health Sciences |isbn=978-1-4377-3650-2 |page=181 |name-list-style=vanc}}</ref>
| frequency       = 2.5 million with [[cardiomyopathy]] (2015)<ref name="GBD2015Pre">{{Cite journal |vauthors=Vos T, Allen C, Arora M, Barber RM, Bhutta ZA, Brown A, etal |date=October 2016 |title=Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015 |journal=Lancet |volume=388 |issue=10053 |pages=1545–1602 |doi=10.1016/S0140-6736(16)31678-6 |pmc=5055577 |pmid=27733282 |collaboration=GBD 2015 Disease and Injury Incidence and Prevalence Collaborators}}</ref>
| deaths          = 354,000 with [[cardiomyopathy]] (2015)<ref name="GBD2015De">{{Cite journal |vauthors=Wang H, Naghavi M, Allen C, Barber RM, Bhutta ZA, Carter A, etal |date=October 2016 |title=Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980-2015: a systematic analysis for the Global Burden of Disease Study 2015 |journal=Lancet |volume=388 |issue=10053 |pages=1459–1544 |doi=10.1016/S0140-6736(16)31012-1 |pmc=5388903 |pmid=27733281 |collaboration=GBD 2015 Mortality and Causes of Death Collaborators}}</ref>
}}

'''Myocarditis''' is [[inflammation]] of the [[cardiac muscle]]. Myocarditis can progress to '''inflammatory cardiomyopathy''' when there is associated ventricular remodeling and cardiac dysfunction due to chronic inflammation.<ref>{{Cite journal |last1=Suresh |first1=Abhilash |last2=Martens |first2=Pieter |last3=Tang |first3=W. H. Wilson |date=October 2022 |title=Biomarkers for Myocarditis and Inflammatory Cardiomyopathy |journal=Current Heart Failure Reports |language=en |volume=19 |issue=5 |pages=346–355 |doi=10.1007/s11897-022-00569-8 |pmid=35913661 |issn=1546-9530|pmc=9340754 }}</ref><ref>{{Cite journal |last1=Tschöpe |first1=Carsten |last2=Ammirati |first2=Enrico |last3=Bozkurt |first3=Biykem |last4=Caforio |first4=Alida L. P. |last5=Cooper |first5=Leslie T. |last6=Felix |first6=Stephan B. |last7=Hare |first7=Joshua M. |last8=Heidecker |first8=Bettina |last9=Heymans |first9=Stephane |last10=Hübner |first10=Norbert |last11=Kelle |first11=Sebastian |last12=Klingel |first12=Karin |last13=Maatz |first13=Henrike |last14=Parwani |first14=Abdul S. |last15=Spillmann |first15=Frank |date=March 2021 |title=Myocarditis and inflammatory cardiomyopathy: current evidence and future directions |journal=Nature Reviews Cardiology |language=en |volume=18 |issue=3 |pages=169–193 |doi=10.1038/s41569-020-00435-x |pmid=33046850 |issn=1759-5002|pmc=7548534 }}</ref> Symptoms can include [[shortness of breath]], [[chest pain]], [[Exercise intolerance|decreased ability to exercise]], and an [[irregular heartbeat]].<ref name=NEJM2009/> The duration of problems can vary from hours to months. Complications may include [[heart failure]], due to [[dilated cardiomyopathy]] or [[cardiac arrest]].<ref name="NEJM2009">{{Cite journal |vauthors=Cooper LT |date=April 2009 |title=Myocarditis |journal=The New England Journal of Medicine |volume=360 |issue=15 |pages=1526–1538 |doi=10.1056/nejmra0800028 |pmc=5814110 |pmid=19357408}}</ref>

<!-- Cause and diagnosis-->
Myocarditis is most often due to a [[viral infection]].<ref name=NEJM2009/> Other causes include [[bacterial infections]], certain medications, toxins and [[autoimmune disorders]].<ref name=NEJM2009/><ref name=Kin2012/> A diagnosis may be supported by an [[electrocardiogram]] (ECG), increased [[troponin]], [[cardiac magnetic resonance imaging|heart MRI]], and occasionally a heart [[biopsy]].<ref name=NEJM2009/><ref name="Kin2012">{{Cite journal |display-authors=6 |vauthors=Kindermann I, Barth C, Mahfoud F, Ukena C, Lenski M, Yilmaz A, Klingel K, Kandolf R, Sechtem U, Cooper LT, Böhm M |date=February 2012 |title=Update on myocarditis |journal=Journal of the American College of Cardiology |volume=59 |issue=9 |pages=779–792 |doi=10.1016/j.jacc.2011.09.074 |pmid=22361396 |doi-access=free}}</ref> An [[echocardiogram|ultrasound of the heart]] is important to rule out other potential causes, such as [[valvular heart disease|heart valve problems]].<ref name=Kin2012/>

Treatment depends on both the severity and the cause.<ref name=NEJM2009/><ref name=Kin2012/> Medications such as [[ACE inhibitors]], [[beta blockers]], and [[diuretics]] are often used.<ref name=NEJM2009/><ref name=Kin2012/> A period of no exercise is typically recommended during recovery.<ref name=NEJM2009/><ref name=Kin2012/> [[Corticosteroids]] or [[intravenous immunoglobulin]] (IVIG) may be useful in certain cases.<ref name=NEJM2009/><ref name=Kin2012/> In severe cases, an [[implantable cardiac defibrillator]] or [[heart transplant]] may be recommended.<ref name=NEJM2009/><ref name=Kin2012/>

In 2013, about 1.5 million cases of acute myocarditis occurred.<ref>{{Cite journal |vauthors=Vos T, Barber RM, Bell B, Bertozzi-Villa A, Biryukov S, Bolliger I, etal |date=August 2015 |title=Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013 |journal=Lancet |volume=386 |issue=9995 |pages=743–800 |doi=10.1016/s0140-6736(15)60692-4 |pmc=4561509 |pmid=26063472 |collaboration=Global Burden of Disease Study 2013 Collaborators}}</ref> While people of all ages are affected, the young are most often affected.<ref>{{Cite book |url=https://books.google.com/books?id=-nIpAgAAQBAJ&pg=PA135 |title=Cellular and Molecular Pathobiology of Cardiovascular Disease |vauthors=Willis M, Homeister JW, Stone JR |date=2013 |publisher=Academic Press |isbn=978-0-12-405525-4 |page=135 |archive-url=https://web.archive.org/web/20171105195029/https://books.google.com/books?id=-nIpAgAAQBAJ&pg=PA135 |archive-date=2017-11-05 |url-status=live}}</ref> It is slightly more common in males than females.<ref name=NEJM2009/> Most cases are mild.<ref name=Kin2012/> In 2015, [[cardiomyopathy]], including myocarditis, resulted in 354,000 deaths, up from 294,000 in 1990.<ref name="GDB2013">{{Cite journal |vauthors=Naghavi M, Wang H, Lozano R, Davis A, Liang X, Zhou M, etal |date=January 2015 |title=Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013 |journal=Lancet |volume=385 |issue=9963 |pages=117–171 |doi=10.1016/S0140-6736(14)61682-2 |pmc=4340604 |pmid=25530442 |collaboration=GBD 2013 Mortality and Causes of Death Collaborators}}</ref><ref name="GBD2015De" /> The initial descriptions of the condition are from the mid-1800s.<ref>{{Cite book |url=https://books.google.com/books?id=xlQ1hqp9ngwC&pg=PA263 |title=Infectious Diseases in Critical Care Medicine |vauthors=Cunha BA |date=2009 |publisher=CRC Press |isbn=978-1-4200-1960-5 |page=263 |archive-url=https://web.archive.org/web/20171105195029/https://books.google.com/books?id=xlQ1hqp9ngwC&pg=PA263 |archive-date=2017-11-05 |url-status=live}}</ref>