ACUTE PERICARDITIS

1. Definition

Acute pericarditis is an inflammatory syndrome of the pericardium with or without pericardial effusion, lasting <6 weeks, characterized by:

  • Typical chest pain
  • Pericardial friction rub
  • ECG changes
  • Pericardial effusion

 

2. Etiology (High-Yield Classification)

A. Infectious (Most common worldwide)

  • Viral (commonest overall)
    Coxsackie A/B, Echovirus, Influenza, EBV, CMV, HIV, COVID-19
  • Bacterial
    • Tuberculosis (most common in India & developing countries)
    • Pneumococcus, Staphylococcus, Streptococcus
  • Fungal (rare): Candida, Histoplasma (immunocompromised)

 

B. Non-Infectious

1. Idiopathic

  • Presumed viral
  • Most cases in developed countries

2. Autoimmune / Inflammatory

  • SLE
  • Rheumatoid arthritis
  • Scleroderma
  • Vasculitis

3. Post-Myocardial Injury Syndromes

  • Early post-MI pericarditis (1–3 days)
  • Dressler syndrome (weeks after MI)
  • Post-cardiac surgery
  • Post-ablation

4. Metabolic

  • Uremic pericarditis
  • Hypothyroidism

5. Malignancy

  • Lung cancer
  • Breast cancer
  • Lymphoma, leukemia

6. Trauma

  • Blunt or penetrating
  • Iatrogenic (PCI, pacemaker)

7. Drug-Induced

  • Hydralazine
  • Procainamide
  • Isoniazid
  • Immune checkpoint inhibitors

 

3. Pathophysiology

  • Inflammation → ↑ vascular permeability
  • Fibrin deposition → fibrinous pericarditis
  • Fluid accumulation → pericardial effusion
  • Rapid accumulation → cardiac tamponade
  • Chronic inflammation → constrictive pericarditis

 

4. Clinical Features

A. Chest Pain (Cardinal Symptom)

  • Sharp, pleuritic
  • Retrosternal or left precordial
  • Worse on inspiration, coughing, lying supine
  • Relieved by sitting up and leaning forward
  • Radiates to trapezius ridge (phrenic nerve involvement)

 

B. Pericardial Friction Rub

  • Pathognomonic
  • High-pitched, scratchy
  • Best heard at left lower sternal border
  • Triphasic (atrial systole, ventricular systole, early diastole)
  • May be transient → requires repeated auscultation

 

C. Systemic Symptoms

  • Fever
  • Malaise
  • Myalgias
  • Features of underlying disease (TB, SLE, uremia)

 

D. Signs of Complications

  • Tamponade: hypotension, JVP rise, muffled heart sounds
  • Large effusion: distant heart sounds
  • Constrictive physiology (late)

 

5. Diagnostic Criteria (ESC Criteria)

Diagnosis requires ≥2 of the following 4:

  1. Typical pericardial chest pain
  2. Pericardial friction rub
  3. Typical ECG changes
  4. New or worsening pericardial effusion

 

6. ECG Changes 

Four Classical Stages

Stage

ECG Findings

I

Diffuse concave ST elevation + PR depression

II

ST segments normalize

III

T-wave inversion

IV

ECG normalization

Key ECG Differentiation from MI

  • ST elevation is diffuse
  • No reciprocal ST depression (except aVR, V1)
  • PR depression is characteristic
  • Troponin may be mildly elevated (myopericarditis)

 

7. Laboratory Findings

  • ↑ CRP, ESR
  • Leukocytosis
  • Troponin I/T ↑ (if myocardial involvement)
  • Renal function (uremia)
  • ANA, RF if autoimmune suspected
  • HIV testing if indicated
  • TB workup (India-specific relevance)

 

8. Imaging

A. Echocardiography (Mandatory in all cases)

  • Detects effusion
  • Assess tamponade
  • Excludes LV dysfunction (myocarditis)
  • Pericardial thickening (chronic)

 

B. Chest X-ray

  • Normal in most
  • Cardiomegaly if large effusion (>250 mL)

 

C. Cardiac MRI

  • Gold standard for:
    • Pericardial inflammation
    • Myopericarditis
  • Late gadolinium enhancement

 

D. CT Chest

  • Pericardial thickening
  • Calcification
  • Malignancy/TB

 

9. Special Types of Acute Pericarditis

1. Uremic Pericarditis

  • Occurs in advanced CKD
  • Chest pain may be absent
  • ECG changes often absent
  • Treatment: urgent dialysis
  • NSAIDs often ineffective

 

2. Tubercular Pericarditis

  • Common in India
  • Subacute presentation
  • Large effusion, tamponade
  • Risk of constriction
  • Requires ATT + steroids

 

3. Myopericarditis

  • Pericarditis + myocardial involvement
  • Elevated troponin
  • Preserved LV function → myopericarditis
  • Reduced LV function → perimyocarditis

 

10. Management

A. General Measures

  • Hospitalize if high-risk
  • Activity restriction until symptom & CRP resolution

 

B. First-Line Therapy 

1. NSAIDs

Drug

 

Ibuprofen

 

Aspirin

 

Indomethacin

 
  • Continue until pain free + CRP normalized
  • Gradual taper

 

2. Colchicine (Reduces Recurrence)

C. Corticosteroids

Indications (Avoid if possible):

  • Autoimmune disease
  • Uremic pericarditis
  • Pregnancy
  • NSAID contraindication

Dose: Prednisolone 0.2–0.5 mg/kg/day
⚠ Increases recurrence risk if used early

 

D. Treatment of Specific Causes

  • TB → ATT + steroids
  • Bacterial → IV antibiotics + drainage
  • Malignancy → Oncology-directed therapy
  • Uremia → Dialysis

 

E. Pericardiocentesis

Indications:

  • Cardiac tamponade
  • Suspected bacterial/TB/malignancy
  • Large symptomatic effusion

 

11. High-Risk Features (Require Admission)

  • Fever >38°C
  • Subacute onset
  • Large effusion
  • Cardiac tamponade
  • Immunosuppression
  • Trauma
  • Failure to respond to NSAIDs
  • Elevated troponin (myopericarditis)

 

12. Complications

  • Recurrent pericarditis
  • Cardiac tamponade
  • Constrictive pericarditis
  • Chronic pericardial effusion

 

13. Recurrent Pericarditis (Brief Overview)

  • Occurs in 15–30%
  • Autoimmune mediated
  • Managed with:
    • NSAIDs + colchicine
    • Steroids (lowest dose)
    • Refractory: azathioprine, IVIG, anakinra

 

14. Key Exam Pearls

  • Chest pain relieved by leaning forward = pericarditis
  • PR depression = atrial involvement
  • Troponin elevation does not exclude pericarditis
  • Colchicine reduces recurrence
  • TB is common cause in India
  • Uremic pericarditis → dialysis, not NSAIDs