Pericarditis

BASICS

Definition: Inflammation of the pericardium, with or without pericardial effusion.
Myopericarditis/perimyocarditis: Myocardial and pericardial involvement.

Idiopathic (85–90%): Mostly viral, immune-related
Common viruses: Coxsackievirus, echovirus, adenovirus, EBV, CMV, hepatitis, influenza, HIV, mumps, varicella, SARS-CoV-2, parvovirus B19
Bacterial: M. tuberculosis, S. aureus, S. pneumoniae, anaerobes (rare in developed countries)
Fungal/Parasite: In immunocompromised
Noninfectious (15–20%):
Acute MI (post-infarction), Dressler syndrome, aortic dissection, uremia, malignancy, radiation, trauma, post-procedural (e.g., post-cardiac surgery), autoimmune/connective tissue disease (SLE, RA, scleroderma, sarcoidosis, IBD, Wegener)
Medications: dantrolene, doxorubicin, hydralazine, isoniazid, mesalamine, methysergide, penicillin, phenytoin, procainamide, rifampin
Vaccination (smallpox, influenza, SARS-CoV-2 mRNA)
Genetics: Familial Mediterranean fever, TRAPS—linked to recurrent pericarditis

Thoracic surgery, CKD, pneumonia, autoimmune disease, radiation (lung/breast CA), chronic infection

Definite pericarditis PLUS:
Symptoms (dyspnea, chest pain, palpitations) and new ECG changes or LV dysfunction on imaging
Elevated cardiac enzymes OR abnormal MRI/gallium scan

Viral prodrome (fever, malaise, myalgias, recent URI)
Acute, sharp, pleuritic chest pain (radiates to trapezius; relieved by leaning forward, worse lying down)
Shortness of breath

Pericardial friction rub: coarse, high-pitched (left lower sternal border, leaning forward)
May be transient, variable phases
S3 may suggest myopericarditis

Labs:
Leukocytosis
↑ ESR/CRP/LDH
↑ Troponin/CK (esp. myopericarditis, but not prognostic)
ECG:
Diffuse ST-elevation (concave), PR depression, low voltage or electrical alternans (large effusion/tamponade)
Echo:
Evaluate for pericardial effusion, tamponade, or myocardial disease
CXR:
Rule out other causes, cardiomegaly if large effusion
CT/MRI:
Evaluate pericardium, complications, pre-op planning
Other:
TSH, TB test, ANA, RF, HIV serology if indicated
Pericardiocentesis: For tamponade, suspected purulent/TB/neoplastic, effusions >20mm on echo

First Line:
NSAIDs: Mainstay for acute pericarditis (Ibuprofen 600 mg TID, Aspirin 1000 mg TID, Indomethacin 50 mg TID; 7–10 days, then taper)
- Aspirin preferred post-MI
- Indomethacin avoid in elderly/CAD
- GI protection with PPI
- Taper only when asymptomatic + normalized CRP/ESR (monitor 1–2 weeks)
Colchicine:
- 0.5–0.6 mg BID (up to 3 months; up to 6 months if recurrent)
- Use with NSAIDs (not alone)
- Only agent proven to prevent recurrence (reduces by ~50%)
- Adjust for renal/hepatic dysfunction
- Monitor CBC, LFTs, CK, creatinine at baseline/1 month; CRP weekly
Pregnancy:
<20 wks: Aspirin preferred; NSAIDs/prednisone allowed
20 wks: Prednisone only; avoid NSAIDs/aspirin/colchicine
Second Line:
Steroids: Only if NSAID/colchicine contraindicated or in CTD/TB pericarditis; avoid in uncomplicated/idiopathic acute pericarditis.
- Low dose (0.2–0.5 mg/kg/day) until symptom/CRP normalization, then taper
- Add calcium/vitamin D; consider bisphosphonate in high-risk
IL-1 antagonists:
- Anakinra (2 mg/kg SC daily, up to 100 mg; 2–6 months)
- Rilonacept (320 mg SC, then 160 mg weekly x12 weeks)
- Use for refractory/recurrent cases
- Monitor for injection site, LFTs, infections

Pericardiocentesis: Tamponade, purulent/TB/neoplastic effusions, refractory large symptomatic effusion
Pericardial window: Recurrent tamponade/effusion unresponsive to other tx
Pericardiectomy: Chronic constrictive pericarditis (NYHA III/IV) only if severe, high-mortality procedure

Admit for:
Major comorbidities
Refractory cases
Uremic/dialysis pericarditis
Suspected/actual tamponade
Immunosuppression, trauma, anticoagulation, myopericarditis, fever >38°C, large effusion, subacute onset, no NSAID/aspirin response
IV fluids: Hypotension/tamponade

Follow-up: 1 week (response, CBC, CRP), then as needed based on risk/echo
Myopericarditis: Lower dose anti-inflammatories, 4–6 weeks exercise restriction (athletes: ≥3 months)
Echo: At 1, 6, 12 months (esp. LV dysfunction)

Recurrence: 15–30% (often idiopathic, viral, autoimmune; usually within 1 week but can occur years later)
Cardiac tamponade: rare, more common in neoplastic, purulent, TB pericarditis
Effusive-constrictive pericarditis: 8–24% of surgical/pericardiocentesis cases (diagnosis: right atrial pressure fails to drop post-pericardiocentesis)
Constrictive pericarditis: rare but severe; requires pericardiectomy
Arrhythmias: Atrial fibrillation/flutter