Acute Pericarditis ,causes, signs and symptoms, diagnosis and treatment

Acute pericarditis is defined as an inflammatory process of the pericardial sac that develops over a period of less than 2 weeks . It may be caused by infections, systemic inflammatory disorders, trauma, or other non-infectious causes.

Etiology

Infectious Causes

Viral (most common): Coxsackievirus B, Echovirus, Influenza, HIV, CMV, EBV
Bacterial: Tuberculosis, Pneumococcus, Staphylococcus, Streptococcus
Fungal: Histoplasma, Aspergillus (rare)
Parasitic: Toxoplasmosis, Amebiasis

Non-Infectious Causes

Autoimmune disorders:
- Systemic lupus erythematosus (SLE)
- Rheumatoid arthritis
- Scleroderma
- Mixed connective tissue disease
Post-myocardial infarction:
- Early: Peri-infarction pericarditis (1–3 days post-MI)
- Late: Dressler syndrome (autoimmune, weeks post-MI)
Uremia
Post-cardiac surgery
Malignancy: Lung, breast, lymphoma, leukemia
Radiation-induced
Trauma or iatrogenic injury
Medications: e.g., procainamide, hydralazine, isoniazid, phenytoin

Pathophysiology

Inflammation leads to increased capillary permeability .
Leakage of plasma proteins (e.g., fibrinogen) into the pericardial space → Exudate formation .
Commonly forms a fibrinous (dry) or serofibrinous pericarditis , which may:
- Resolve with treatment
- Progress to chronic pericarditis , adhesions , or constrictive pericarditis

Clinical Features

Classic Triad of Acute Pericarditis

Pleuritic chest pain
Pericardial friction rub
ECG changes

Chest Pain

Sharp and pleuritic , worse on inspiration, coughing, swallowing
Improves with sitting up and leaning forward
Worsens when lying supine
May radiate to neck, shoulders, or back (phrenic nerve irritation)

Pericardial Friction Rub

High-pitched, scratchy/squeaky sound
Best heard at left lower sternal border
Varies with position and respiration

Electrocardiogram (ECG) Findings

Diffuse ST-segment elevation (concave, "saddle-shaped")
PR-segment depression
No reciprocal changes (unlike MI)
May progress through 4 stages:
1. ST elevation & PR depression
2. ST returns to baseline
3. T wave inversion
4. Normalization

Diagnosis

Diagnosis is clinical but supported by tests.

Diagnostic Criteria (At least 2 of 4 required):

Pleuritic chest pain
Pericardial friction rub
Typical ECG changes
Pericardial effusion (seen on echocardiography)

Supporting Investigations

ECG : as above
Echocardiography : for effusion or tamponade
Chest X-ray : often normal; may show enlarged cardiac silhouette
Inflammatory markers : ↑ ESR, CRP, leukocytosis
Troponin : may be elevated if myocardium involved (myopericarditis)
Pericardial fluid analysis : if large effusion or tamponade
Autoimmune/viral serologies : if indicated

Treatment

General Management

Rest : Limit physical activity until symptom resolution and normalization of CRP

First-Line Therapy

NSAIDs (e.g., ibuprofen 600–800 mg TID or aspirin 650–1000 mg TID)
Colchicine : 0.5–1 mg/day for 3 months (↓ recurrence)

Second-Line or Adjunct

Corticosteroids (e.g., prednisone): Reserved for NSAID-resistant cases or autoimmune causes

Etiology-Specific Management

Bacterial pericarditis : IV antibiotics + drainage if needed
Tuberculous pericarditis : Anti-TB therapy ± steroids
Uremic pericarditis : Urgent dialysis
Neoplastic pericarditis : Pericardiocentesis + oncologic management

Complications

Pericardial effusion
Cardiac tamponade : Life-threatening; requires emergency pericardiocentesis
Constrictive pericarditis : Chronic fibrosis causing diastolic dysfunction
Recurrent pericarditis

Recurrent Pericarditis

Occurs in ~15–30% of patients
More common after viral pericarditis or autoimmune pericarditis
Treatment:
- NSAIDs + colchicine (first-line)
- Corticosteroids (for autoimmune/NSAID-refractory)
- Immunomodulators in refractory cases: anakinra , azathioprine