Myocarditis: Difference between revisions
No edit summary
 
(21 intermediate revisions by 6 users not shown)
Line 1: Line 1:
{{Adult top}} [[myocarditis (peds)]]
==Background==
==Background==
*Inflammatory cardiomyopathy (dilated cardiomyopathy) caused by necrosis of myocytes from infectious agents, their toxins, and cytotoxic effects of activated host immunity
[[File:KVIR A 2180951 F0001 OC.jpg|thumb|Triggers of myocarditis. Myocarditis can be induced by both infectious and non-infectious pathogens, with viral infection being the most common cause (red background).]]
*Majority caused by enterovirus (Cocksackie B) and adenovirus. Also influenza A/B, Hep B, B Hemolytic Streptococcus, Mycoplasma, Mumps, CMV and Toxoplasma (cardiac transplant), Chagas (leading cause worldwide) Trichinosis, Diphtheria, Lyme
*Inflammatory cardiomyopathy caused by damage and necrosis of myocytes
*Drugs: Doxorubicin, Cocaine
**Viral-induced is the most common etiology<ref>Cooper LT Jr. Myocarditis. N Engl J Med. 2009 Apr 9;360(15):1526-38. doi: 10.1056/NEJMra0800028. PMID: 19357408; PMCID: PMC5814110.</ref>
*Clinical presentation ranges from smoldering heart failure to fulminant cardiogenic shock or sudden death
*Maintain a high index of suspicion in younger patients without traditional CAD risk factors
 
===Causes===
*Infectious agents
**[[Enterovirus]] (Coxsackie B) and [[adenovirus]] most common
**[[Influenza]] A and B
**[[Hepatitis B]]
**[[Beta-hemolytic streptococcus]]
**[[Mycoplasma]]
**[[Mumps]]
**[[CMV]]
**[[Toxoplasma]]
**[[Chagas]] (most common cause worldwide)
**[[Trichinosis]]
**[[Sarcoidosis]]
**[[Systemic lupus erythematosus]]
**[[Diphtheria]]
**[[Lyme disease]]
**[[COVID-19]]<ref>[https://link.springer.com/article/10.1007/s11739-021-02635-w Mele D, Flamigni F, Rapezzi C, Ferrari R. Myocarditis in COVID-19 patients: current problems. Internal and Emergency Medicine. 2021. doi:10.1007/s11739-021-02635-w]</ref>
*Drugs
**[[Doxorubicin]]
**[[Cocaine]]


===Phases===
===Phases===
*Acute: Viral cytotoxicity and focal necrosis  
*Acute
*Subacute: Host's humoral/immune response leading to further cell injury  
**Direct cytotoxicity and focal necrosis from viral, autoimmune, or toxins
*Chronic: Diffuse myocardial fibrosis and cardiac dysfunction
*Subacute
**Host's humoral/immune response (viral molecular mimicry and anti-myocyte antibody production) leading to further cell injury  
*Chronic
**Diffuse myocardial fibrosis and cardiac dysfunction


==Clinical Features==
==Clinical Features==
*Typically young/few risk factors for CAD  
*Typically young patients (20 - 50 years) with few risk factors for CAD  
**Age at onset typically between 20-50 years
*[[Chest pain]] or chest pressure/tightness
*[[Chest pain]]  
*[[Flu-like symptoms]]
*No sensitive symptom or sign but can have flu like syndrome: fever, fatigue, myalgia, nausea and vomiting; tachycardia (out of proportion to fever), tachypnea, new onset CHF
**[[Fever]], [[fatigue]], [[myalgia]], [[nausea and vomiting]]
*In Peds: grunting, retractions, ronchi. Infants may have fulminant syndrome: Fever, cyanosis, respiratory distress, tachycardia, cardiac failure, ventricular dysrhythmias
**[[Tachycardia]] (out of proportion to fever)
*May have pericardial friction rub
**[[Tachypnea]]
*Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids.
*New onset [[congestive heart failure]], which may include fatigue, orthopnea, or dyspnea on exertion
*Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids
*Pediatric patients: See [[myocarditis (peds)]]
 


==Differential Diagnosis==
==Differential Diagnosis==
*Acute [[MI]]  
''Consider other causes of [[CHF]]''
*[[Pericarditis ]]
{{Chest Pain DDX}}
*[[CHF]]
 


==Evaluation==
==Evaluation==
*[[ECG]]: Sinus tachycardia, low voltages, [[prolonged QTc]], AV block, Acute MI pattern (Usually >1 vessel distribution)
[[File:PericarditisMyocarditis.jpg|thumb|Diffuse ST elevation in a patient with combined myocarditis and [[pericarditis]].]]
*TropI: Elevated  
*[[ECG]] needs to be obtained to rule out ischemia. Myocarditis may exhibit the following findings:
*Echo: Decreased LVEF, global hypokinesis, regional wall motion abnormalities  
**Sinus [[tachycardia]]
*Contrast MR
**Nonspecific ST-T changes
*Nuclear Study: Widespread uptake indicating myocyte necrosis  
**[[low voltage ECG|Low voltages]]
*Viral titers
**[[Prolonged QTc]]
*Endocardial biopsy: Gold standard
**[[AV block]] may be present in [[Lyme disease]] or [[Sarcoidosis]] as the infiltrative process involves the AV node
**Wide QRS, including [[Left bundle branch block]], may be seen
**Note that a normal EKG does not rule out myocarditis
*Elevated [[troponin]] or [[Brain natriuretic peptide]]
*CXR
**May demonstrate indirect signs such as cardiomegaly, pulmonary edema, or pleural effusion
*[[Echocardiography]]
**Decreased LVEF
**Global hypokinesis or regional wall motion abnormalities  
**Changes to LV geometry
**Detection of concomitant pericarditis (if present, would then be named myopericarditis)
*Cardiac MRI with contrast
**Noninvasive gold standard for structural-functional changes
*Nuclear Study
**Widespread uptake indicating myocyte necrosis  
*Viral titres
*Endomyocardial biopsy (EMB): Invasive gold standard, but rarely used
*Coronary angiography is indicated in selected patients where [[acute coronary syndrome]] is suspected
 


==Management==
==Management==
*Acute Phase: Antiviral agents may be effective with replicating virus: Pleconaril/[[Ribavirin]]  
*Acute phase
*Subacute: Studies have not shown efficacy of immunosupressants. Peds: High dose [[IVIG]]
**Discontinue offending agent, if possible/known
*Chronic: Treat CHF symptoms, Ventricular Assist Devices (VAD), cardiac transplant
**Antiviral agents (Pleconaril/[[Ribavirin]]) may be effective for specific viruses
**COVID-related: limited/conflicting evidence regarding efficacy of high-dose [[steroids]] and/or [[IVIG]] <ref>[https://link.springer.com/article/10.1007/s11739-021-02635-w Mele D, Flamigni F, Rapezzi C, Ferrari R. Myocarditis in COVID-19 patients: current problems. Internal and Emergency Medicine. 2021. doi:10.1007/s11739-021-02635-w]</ref>
*Subacute phase
**Studies have not shown efficacy of immunosuppressants for acute myocarditis, unless in specific EMB-proven cases
**Pediatric patients may receive high-dose [[IVIG]]
*Chronic phase
**Treatment for CHF symptoms, which may include GDMT meds or diuresis
**Ventricular Assist Devices ([[LVAD|VAD]])
**Cardiac transplant


==Disposition==
==Disposition==
*If [[CHF]]: Admit to monitored bed; ICU for hemodynamic instability
*If [[CHF]] is present, admit to a monitored bed
*If hemodynamically unstable, admit to ICU
 
==Prognosis==
*Fulminant myocarditis has best prognosis  
*Fulminant myocarditis has best prognosis  
*Mortality: 20% 1 yr/ 50% 5 yr  
*Mortality: 20% 1 yr/ 50% 5 yr  
Line 44: Line 103:


==Complications==
==Complications==
*Ventricular dysrhythmias  
*[[Ventricular dysrhythmias]]
*LV anneurysm
*[[LV aneurysm]]
*[[CHF]]
*[[CHF]]


==See Also==
==See Also==
*[[Cardiomyopathy]]  
*[[Cardiomyopathy]]  
*[[Pericarditis]]  
*[[Pericarditis]]
 
==External Links==
2024 ACC Expert Consensus on Myocarditis<ref>Writing Committee; Drazner MH, Bozkurt B, Cooper LT, Aggarwal NR, Basso C, Bhave NM, Caforio ALP, Ferreira VM, Heidecker B, Kontorovich AR, Martín P, Roth GA, Van Eyk JE. 2024 ACC Expert Consensus Decision Pathway on Strategies and Criteria for the Diagnosis and Management of Myocarditis: A Report of the American College of Cardiology Solution Set Oversight Committee. J Am Coll Cardiol. 2025 Feb 4;85(4):391-431. doi: 10.1016/j.jacc.2024.10.080. Epub 2024 Dec 10. PMID: 39665703.</ref>


==References==
==References==
<references/>
<references/>
[[Category:Cardiology]]
[[Category:Cardiology]]

Latest revision as of 20:11, 25 June 2025

This page is for adult patients. For pediatric patients, see: myocarditis (peds)

Background

Triggers of myocarditis. Myocarditis can be induced by both infectious and non-infectious pathogens, with viral infection being the most common cause (red background).
  • Inflammatory cardiomyopathy caused by damage and necrosis of myocytes
    • Viral-induced is the most common etiology[1]
  • Clinical presentation ranges from smoldering heart failure to fulminant cardiogenic shock or sudden death
  • Maintain a high index of suspicion in younger patients without traditional CAD risk factors

Causes

Phases

  • Acute
    • Direct cytotoxicity and focal necrosis from viral, autoimmune, or toxins
  • Subacute
    • Host's humoral/immune response (viral molecular mimicry and anti-myocyte antibody production) leading to further cell injury
  • Chronic
    • Diffuse myocardial fibrosis and cardiac dysfunction

Clinical Features


Differential Diagnosis

Consider other causes of CHF

Chest pain

Critical

Emergent

Nonemergent


Evaluation

Diffuse ST elevation in a patient with combined myocarditis and pericarditis.
  • ECG needs to be obtained to rule out ischemia. Myocarditis may exhibit the following findings:
  • Elevated troponin or Brain natriuretic peptide
  • CXR
    • May demonstrate indirect signs such as cardiomegaly, pulmonary edema, or pleural effusion
  • Echocardiography
    • Decreased LVEF
    • Global hypokinesis or regional wall motion abnormalities
    • Changes to LV geometry
    • Detection of concomitant pericarditis (if present, would then be named myopericarditis)
  • Cardiac MRI with contrast
    • Noninvasive gold standard for structural-functional changes
  • Nuclear Study
    • Widespread uptake indicating myocyte necrosis
  • Viral titres
  • Endomyocardial biopsy (EMB): Invasive gold standard, but rarely used
  • Coronary angiography is indicated in selected patients where acute coronary syndrome is suspected


Management

  • Acute phase
    • Discontinue offending agent, if possible/known
    • Antiviral agents (Pleconaril/Ribavirin) may be effective for specific viruses
    • COVID-related: limited/conflicting evidence regarding efficacy of high-dose steroids and/or IVIG [3]
  • Subacute phase
    • Studies have not shown efficacy of immunosuppressants for acute myocarditis, unless in specific EMB-proven cases
    • Pediatric patients may receive high-dose IVIG
  • Chronic phase
    • Treatment for CHF symptoms, which may include GDMT meds or diuresis
    • Ventricular Assist Devices (VAD)
    • Cardiac transplant

Disposition

  • If CHF is present, admit to a monitored bed
  • If hemodynamically unstable, admit to ICU

Prognosis

  • Fulminant myocarditis has best prognosis
  • Mortality: 20% 1 yr/ 50% 5 yr
  • Children with 70% survival rate at 5 yrs

Complications

See Also

External Links

2024 ACC Expert Consensus on Myocarditis[4]

References

  1. ↑ Cooper LT Jr. Myocarditis. N Engl J Med. 2009 Apr 9;360(15):1526-38. doi: 10.1056/NEJMra0800028. PMID: 19357408; PMCID: PMC5814110.
  2. ↑ Mele D, Flamigni F, Rapezzi C, Ferrari R. Myocarditis in COVID-19 patients: current problems. Internal and Emergency Medicine. 2021. doi:10.1007/s11739-021-02635-w
  3. ↑ Mele D, Flamigni F, Rapezzi C, Ferrari R. Myocarditis in COVID-19 patients: current problems. Internal and Emergency Medicine. 2021. doi:10.1007/s11739-021-02635-w
  4. ↑ Writing Committee; Drazner MH, Bozkurt B, Cooper LT, Aggarwal NR, Basso C, Bhave NM, Caforio ALP, Ferreira VM, Heidecker B, Kontorovich AR, Martín P, Roth GA, Van Eyk JE. 2024 ACC Expert Consensus Decision Pathway on Strategies and Criteria for the Diagnosis and Management of Myocarditis: A Report of the American College of Cardiology Solution Set Oversight Committee. J Am Coll Cardiol. 2025 Feb 4;85(4):391-431. doi: 10.1016/j.jacc.2024.10.080. Epub 2024 Dec 10. PMID: 39665703.
Retrieved from "https://www.wikem.org/w/index.php?title=Myocarditis&oldid=376786"