Treatment of Post-Myocardial Infarction Pericarditis
For early post-MI pericarditis, aspirin plus colchicine is the recommended treatment, while Dressler syndrome (late post-MI pericarditis) should be treated with the same anti-inflammatory regimen used for post-cardiac injury syndromes. 1
Early Post-Infarction Pericarditis (Days 2-3 After MI)
First-Line Treatment: Aspirin Plus Colchicine
- Aspirin is the preferred NSAID because it increases coronary flow and has antiplatelet effects demonstrated at doses up to 1.5 g/day 1, 2
- Dosing: Aspirin 500-1,000 mg every 6-8 hours (range 1.5-4 g/day) with gastroprotection 2
- Add colchicine 0.5-0.6 mg once or twice daily for 3 months (dose-adjust for weight: 0.5 mg twice daily if ≥70 kg, 0.5 mg once daily if <70 kg) 2
- Most cases are self-limited and respond well to this regimen 1, 3
Important Clinical Context
- This complication is now rare in the primary PCI era and typically occurs only with late reperfusion or failed coronary reperfusion 1
- Treatment is generally supportive, as most cases resolve spontaneously 1
- Only persistent symptomatic cases require aspirin plus colchicine 1
Critical Warning Signs
- Pericardial effusion >10 mm thickness requires urgent investigation for possible subacute rupture 1, 2
- Two-thirds of patients with effusions >10 mm may develop tamponade or free wall rupture 1
- Hospitalization is mandatory to observe for tamponade and adjust treatment 1, 2
Dressler Syndrome (Late Post-MI Pericarditis, 1-2 Weeks After MI)
Treatment Approach
- Treat identically to post-cardiac injury syndromes with aspirin plus colchicine 1, 2
- This syndrome is extremely rare (<1%) in the primary PCI era 1
- May reflect larger infarct size and/or late reperfusion 1
Treatment Duration and Tapering
- Continue therapy for several weeks to months, even after effusion disappears 1, 2
- Taper aspirin gradually by 250-500 mg every 1-2 weeks only after symptoms resolve and CRP normalizes 2, 4
- Taper one drug at a time before gradually discontinuing colchicine 2
Medications to AVOID
- Other NSAIDs (except ibuprofen) risk thinning the infarction zone and should be avoided 1
- Ibuprofen is acceptable if aspirin cannot be used, as it increases coronary flow 1
- Corticosteroids should be avoided or used only for refractory symptoms because they may delay myocardial infarction healing 1, 2
Refractory Cases (Second-Line Options)
- Corticosteroid therapy can be used for refractory symptoms only, but with extreme caution due to delayed MI healing 1, 2
- Long-term oral corticosteroids (3-6 months) or pericardiocentesis with intrapericardial triamcinolone (300 mg/m²) are options 1, 2
- Colchicine has been successfully used in steroid-dependent cases to facilitate steroid withdrawal 5
Prognosis and Monitoring
- Although pericarditis is associated with larger infarct size, in-hospital and 1-year mortality are similar in patients with and without pericarditis 1
- Early post-MI pericarditis remains a marker of larger infarct size but without independent prognostic significance 1
- Rare complications include hemopericardium, cardiac tamponade, and constrictive pericarditis 3
- Monitor CRP levels to guide treatment duration and assess response 4