Myocarditis: Difference between revisions

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== Background  ==
== Background  ==
*Inflammatory cardiomyopathy (dilated cardiomyopathy) caused by necrosis of myocytes from infectious agents, their toxins, and cytotoxic effects of activated host immunity  
*Inflammatory cardiomyopathy (dilated cardiomyopathy) caused by necrosis of myocytes from infectious agents, their toxins, and cytotoxic effects of activated host immunity  
*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  
*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  
*Drugs: Doxorubicin, Cocaine
*Drugs: Doxorubicin, Cocaine


*Three phases:
===Phases===
**Acute: Viral cytotoxicity and focal necrosis  
*Acute: Viral cytotoxicity and focal necrosis  
**Subacute: Host's humoral/immune response leading to further cell injury  
*Subacute: Host's humoral/immune response leading to further cell injury  
**Chronic: Diffuse myocardial fibrosis and cardiac dysfunction
*Chronic: Diffuse myocardial fibrosis and cardiac dysfunction


== Clinical Features  ==
== Clinical Features  ==
*Typically young/few risk factors for CAD  
*Typically young/few risk factors for CAD  
*Chest Pain
*[[Chest pain]]
*No sensitive symptom or sign but can have flu like syndrome: fever, fatigue, myalgia, N/V; tachycardia (out of proportion to fever), tachypnea, new onset CHF  
*No sensitive symptom or sign but can have flu like syndrome: fever, fatigue, myalgia, N/V; tachycardia (out of proportion to fever), tachypnea, new onset CHF  
*In Peds: grunting, retractions, ronchi. Infants may have fulminant syndrome: Fever, cyanosis, respiratory distress, tachycardia, cardiac failure, ventricular dysrhythmias  
*In Peds: grunting, retractions, ronchi. Infants may have fulminant syndrome: Fever, cyanosis, respiratory distress, tachycardia, cardiac failure, ventricular dysrhythmias  
*May have pericardial friction rub
*May have pericardial friction rub
*Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids.
*Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids.
== Differential Diagnosis ==
*Acute [[MI]]
*[[Pericarditis ]]
*[[CHF]]


== Diagnosis  ==
== Diagnosis  ==
 
*[[ECG]]: Sinus tach, low voltages, prolonged QTc, AV block, Acute MI pattern (Usually >1 vessel distribution)  
*ECG: Sinus tach, low voltages, prolonged QTc, AV block, Acute MI pattern (Usually >1 vessel distribution)  
*TropI: Elevated  
*TropI: Elevated  
*Echo: Decreased LVEF, global hypokinesis, regional wall motion abnormalities  
*Echo: Decreased LVEF, global hypokinesis, regional wall motion abnormalities  
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*Viral titers  
*Viral titers  
*Endocardial biopsy: Gold standard
*Endocardial biopsy: Gold standard
== DDx  ==
*Acute MI
*Pericarditis
*CHF


== Treatment  ==
== Treatment  ==
*Acute Phase: Antiviral agents may be effective with replicating virus: Pleconaril/Ribavirin  
*Acute Phase: Antiviral agents may be effective with replicating virus: Pleconaril/Ribavirin  
*Subacute: Studies have not shown efficacy of immunosupressants. Peds: High dose IVIG  
*Subacute: Studies have not shown efficacy of immunosupressants. Peds: High dose IVIG  
*Chronic: Treat CHF symptoms, Ventricular Assist Devices (VAD), cardiac transplant
*Chronic: Treat CHF symptoms, Ventricular Assist Devices (VAD), cardiac transplant


== Dispo ==
== Disposition ==
 
*If [[CHF]]: Admit to monitored bed; ICU for hemodynamic instability  
*If CHF: Admit to monitored bed; ICU for hemodynamic instability  
*Fulminant myocarditis has best prognosis  
*Fulminant myocarditis has best prognosis  
*Mortality: 20% 1 yr/ 50% 5 yr  
*Mortality: 20% 1 yr/ 50% 5 yr  
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== See Also  ==
== See Also  ==
*[[Cardiomyopathy]]
*[[Pericarditis]]


[[Cardiomyopathy]]
== References ==
 
[[Pericarditis]]
 
== Source  ==
Rosen's, Tintinalli


[[Category:Cards]]
[[Category:Cards]]

Revision as of 11:55, 29 June 2015

Background

  • Inflammatory cardiomyopathy (dilated cardiomyopathy) caused by necrosis of myocytes from infectious agents, their toxins, and cytotoxic effects of activated host immunity
  • 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
  • Drugs: Doxorubicin, Cocaine

Phases

  • Acute: Viral cytotoxicity and focal necrosis
  • Subacute: Host's humoral/immune response leading to further cell injury
  • Chronic: Diffuse myocardial fibrosis and cardiac dysfunction

Clinical Features

  • Typically young/few risk factors for CAD
  • Chest pain
  • No sensitive symptom or sign but can have flu like syndrome: fever, fatigue, myalgia, N/V; tachycardia (out of proportion to fever), tachypnea, new onset CHF
  • In Peds: grunting, retractions, ronchi. Infants may have fulminant syndrome: Fever, cyanosis, respiratory distress, tachycardia, cardiac failure, ventricular dysrhythmias
  • May have pericardial friction rub
  • Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids.

Differential Diagnosis

Diagnosis

  • ECG: Sinus tach, low voltages, prolonged QTc, AV block, Acute MI pattern (Usually >1 vessel distribution)
  • TropI: Elevated
  • Echo: Decreased LVEF, global hypokinesis, regional wall motion abnormalities
  • Contrast MR
  • Nuclear Study: Widespread uptake indicating myocyte necrosis
  • Viral titers
  • Endocardial biopsy: Gold standard

Treatment

  • Acute Phase: Antiviral agents may be effective with replicating virus: Pleconaril/Ribavirin
  • Subacute: Studies have not shown efficacy of immunosupressants. Peds: High dose IVIG
  • Chronic: Treat CHF symptoms, Ventricular Assist Devices (VAD), cardiac transplant

Disposition

  • If CHF: Admit to monitored bed; ICU for hemodynamic instability
  • Fulminant myocarditis has best prognosis
  • Mortality: 20% 1 yr/ 50% 5 yr
  • Children with 70% survival rateat 5 yrs
  • Complications
    • Vent. Dysrhythmias
    • LV anneurysm
    • CHF

See Also

References