What is the management for a patient with suspected myopericarditis presenting with chest pain, shortness of breath, or palpitations?

Management of Suspected Myopericarditis

Hospitalize all patients with suspected myopericarditis immediately for diagnosis, monitoring, and differentiation from acute coronary syndrome, regardless of clinical stability. 1, 2

Initial Diagnostic Workup

Mandatory Immediate Testing

• Coronary angiography (or coronary CT angiography based on risk factors) is required to exclude acute coronary syndrome, as myopericarditis can present identically to MI with elevated troponins and chest pain 1, 2
• Transthoracic echocardiography (TTE) must be performed urgently to assess for pericardial effusion, ventricular wall motion abnormalities, left ventricular dysfunction, valvular abnormalities, and restrictive physiology 1
• Cardiac MRI with gadolinium contrast is the gold standard (Class I recommendation) to confirm myocardial and pericardial inflammation, determine extent of involvement, and distinguish myopericarditis from MINOCA and other cardiomyopathies 1, 2
  • CMR has 94-100% sensitivity for detecting pericardial inflammation 1
  • Should be performed within 2 weeks of presentation for optimal diagnostic yield 1
  • Shows characteristic late gadolinium enhancement, myocardial edema, and pericardial thickening 1

Additional Diagnostic Considerations

• ECG typically shows widespread concave ST-elevation with PR depression, distinguishing it from the localized convex ST-elevation of MI 3
• Cardiac biomarkers (troponin, CPK-MB) will be elevated, confirming myocardial involvement 2, 4
• Cardiac CT may be reasonable (Class IIb) to assess pericardial thickening if CMR is contraindicated 1

Medical Management

Anti-Inflammatory Therapy

Use reduced doses of NSAIDs compared to isolated pericarditis, as animal models suggest NSAIDs may enhance myocardial inflammation and increase mortality in myocarditis. 1, 2

• Aspirin 1500-3000 mg/day OR Ibuprofen 1200-2400 mg/day OR Indomethacin 75-150 mg/day at the lower end of dosing ranges 1, 2
• Therapy is primarily aimed at symptom control (chest pain), not disease modification 1, 4, 5
• Corticosteroids should be reserved as second-line therapy only for contraindications, intolerance, or failure of NSAIDs 1
• Colchicine has insufficient evidence for routine use in myopericarditis (unlike isolated pericarditis where it is well-established) 1

Critical Activity Restriction

Mandate complete rest and avoidance of all physical activity beyond normal sedentary activities for a minimum of 6 months from illness onset. 1, 2, 6

This restriction is non-negotiable because:

• Sudden cardiac death has been reported in military personnel and athletes (including soccer players and swimmers) after strenuous exertion, even without prodromic symptoms 1, 6
• The risk is arrhythmic sudden death during the acute phase with exertion, not chronic heart failure 6
• This differs from isolated pericarditis, where return to exercise is permissible much earlier 1

Requirements Before Returning to Activity (After 6 Months)

• Complete resolution of symptoms 2
• Normalization of myocardial injury markers 2
• Normal left ventricular function on repeat echocardiography 2
• Absence of arrhythmias on exercise stress testing 2
• Holter monitoring showing no spontaneous arrhythmias 2
• Repeat cardiac MRI at 3-4 months demonstrating resolution of inflammatory changes 2

Monitoring and Follow-Up

• Continuous cardiac monitoring during hospitalization to detect arrhythmias 2
• Serial echocardiography to assess LV function evolution 1, 2
• Repeat CMR at 3-4 months to document resolution of inflammation before activity clearance 2
• Ideally, hospitalization should occur at an advanced heart failure center if any hemodynamic compromise develops 2

Prognosis

Myopericarditis generally has excellent prognosis with appropriate management, with observational series showing no evolution to heart failure or mortality in most patients with preserved LV function. 1, 2, 6, 4

• Complete remission typically occurs within 3-6 months 4
• Troponin elevation does not confer worse long-term prognosis in patients with preserved LV function 1, 4
• The primary risk is sudden cardiac death from arrhythmias during the acute phase with exertion, not chronic heart failure 6
• Up to 14% may report atypical, non-limiting chest discomfort on follow-up despite objective normalization 5

Common Pitfalls to Avoid

• Do not discharge patients with elevated troponins and suspected myopericarditis—hospitalization is mandatory even if they appear clinically stable 1, 2
• Do not use full-dose NSAIDs as in isolated pericarditis—lower doses are recommended due to potential harm in myocarditis 1, 2
• Do not allow return to physical activity before 6 months—this is associated with sudden cardiac death risk 1, 2, 6
• Do not assume good prognosis means early activity resumption is safe—the benign long-term prognosis only applies with appropriate activity restriction during the acute phase 1, 6
• Do not skip coronary evaluation—acute coronary syndrome must be definitively excluded given overlapping presentations 1, 2