Myocarditis: Difference between revisions

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==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]]  
*[[Chest pain]]  
*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
*Pericardial friction rub
*In Peds: grunting, retractions, ronchi. Infants may have fulminant syndrome: Fever, cyanosis, respiratory distress, tachycardia, cardiac failure, ventricular dysrhythmias  
*Flu like syndrome
*May have pericardial friction rub
**Fever, fatigue, myalgia, nausea and vomiting
*Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids.
**Tachycardia (out of proportion to fever)
**Tachypnea
*New onset [[congestive heart failure]]
*Pediatric patients:
**Grunting
**Retractions
**Ronchi
*Infants may have fulminant syndrome
**Fever
**Cyanosis
**Respiratory distress
**Tachycardia
**Heart failure
**Ventricular dysrhythmias  
 
*Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids


==Differential Diagnosis==
==Differential Diagnosis==

Revision as of 01:22, 12 March 2019

Background

  • Inflammatory (dilated) cardiomyopathy caused by necrosis of myocytes
  • 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
      • Diphtheria
      • Lyme disease
    • 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 patients (20 - 50 years) with few risk factors for CAD
  • Chest pain
  • Pericardial friction rub
  • Flu like syndrome
    • Fever, fatigue, myalgia, nausea and vomiting
    • Tachycardia (out of proportion to fever)
    • Tachypnea
  • New onset congestive heart failure
  • Pediatric patients:
    • Grunting
    • Retractions
    • Ronchi
  • Infants may have fulminant syndrome
    • Fever
    • Cyanosis
    • Respiratory distress
    • Tachycardia
    • Heart failure
    • Ventricular dysrhythmias
  • Consider this diagnosis in the septic-appearing patient who gets WORSE after receiving IV fluids

Differential Diagnosis

Consider other causes of CHF

Chest pain

Critical

Emergent

Nonemergent

Evaluation

  • ECG: Sinus tachycardia, 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

Management

  • 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 rate at 5 yrs

Complications

  • Ventricular dysrhythmias
  • LV anneurysm
  • CHF

See Also

References