Treatment of Perimyocarditis
The treatment of perimyocarditis should follow a stepwise approach with first-line therapy consisting of high-dose NSAIDs (such as ibuprofen 600mg every 8 hours) combined with colchicine (0.5mg twice daily for patients ≥70kg or 0.5mg once daily for patients <70kg) for at least 3 months. 1
Initial Management
First-Line Therapy
NSAIDs: High-dose aspirin (750-1000mg every 8 hours) or ibuprofen (600mg every 8 hours) 2
- Continue until symptoms resolve and CRP normalizes
- Always provide gastroprotection while on NSAIDs/aspirin
Colchicine: Add to NSAID therapy 1, 3
- Dosing: 0.5mg twice daily for patients ≥70kg or 0.5mg once daily for patients <70kg
- Duration: At least 3 months for first episode
- Reduces recurrence rates from 30-37.5% to 8-16.7% 3
Monitoring
- Weekly clinical evaluation with serial CRP measurements 2
- Continue anti-inflammatory therapy until complete symptom resolution and CRP normalization 1
- Serial echocardiography to monitor for pericardial effusion and cardiac function 2
Second-Line Therapy
For Patients Not Responding to First-Line Treatment
- Corticosteroids: Consider only if no response to NSAIDs and colchicine 1, 3
- Note: Corticosteroids are not recommended as first-line therapy due to increased risk of recurrence 1
For Specific Viral Etiologies (if confirmed)
- For Coxsackie B virus: Consider interferon alpha or beta 2.5 million IU/m² subcutaneously 3 times per week 1, 2
- For CMV: Consider hyperimmunoglobulin 1
- For adenovirus and parvovirus B19: Consider immunoglobulin treatment 1
Management of Recurrent Perimyocarditis
- Continue colchicine for at least 6 months for first recurrence 3
- For multiple recurrences:
- Consider IL-1 blockers which have demonstrated efficacy and may be preferred over corticosteroids 3
Activity Restriction
- Restrict physical activity until symptoms resolve and CRP normalizes 2
- Athletes should restrict activity for a minimum of 3 months 2
Hospitalization Criteria
- Fever >38°C
- Large pericardial effusion
- Signs of cardiac tamponade
- Failure to respond to outpatient treatment 1, 2
Diagnostic Considerations
- Definitive diagnosis of viral etiology requires PCR or in-situ hybridization of pericardial effusion/tissue (level of evidence B, class IIa indication) 1, 2
- A four-fold rise in serum antibody levels is suggestive but not diagnostic for viral pericarditis 1, 2
Prognosis
- With appropriate treatment, 70-85% of patients have a benign course 3
- Risk of constrictive pericarditis is <1% in idiopathic cases 2
- Recurrence rate is 15-30% without colchicine, reduced to 8-15% with colchicine 2
Special Considerations
- In cases of perimyocarditis associated with systemic diseases (e.g., autoimmune conditions), treat the underlying condition alongside the perimyocarditis 4
- For perimyocarditis associated with COVID-19 or other specific infections, the same general principles apply, but additional specific treatments may be necessary 5
Common Pitfalls to Avoid
- Using corticosteroids as first-line therapy (increases risk of recurrence)
- Discontinuing anti-inflammatory therapy too early (continue until complete symptom resolution and CRP normalization)
- Failing to add colchicine to NSAID therapy (significantly reduces recurrence risk)
- Inadequate activity restriction during the acute phase
- Missing underlying systemic diseases that may be causing perimyocarditis