Pericardial Anatomy & Effusion - Sac's Fluid Saga
- Pericardial Sac:
- Layers: Outer fibrous; inner serous (parietal & visceral/epicardium).
- Space: Between serous layers; normal fluid <50ml (lubrication).
- Innervation: Phrenic nerve (pain referral to shoulder).
- Pericardial Effusion: Abnormal fluid accumulation (>50ml).
- Types: Transudative (e.g., CHF) or Exudative (e.g., infection, malignancy).
- Key Causes: TB, viral infections, malignancy, uremia, autoimmune (SLE), Dressler's syndrome.
- Imaging Findings:
- Echocardiography: Gold standard. Detects ≥15-20ml; assesses hemodynamics.
- CXR: Globular heart (see below); epicardial fat pad sign ("Oreo cookie sign").
⭐ Water bottle sign (globular cardiac silhouette) on CXR is a classic indicator of large pericardial effusion (typically >250ml).
- CT/MRI: For complex/loculated effusions, pericardial thickening.

Cardiac Tamponade - Pressure Cooker Crisis
Life-threatening compression from rapid pericardial fluid accumulation, impairing diastolic filling and reducing cardiac output.
- Key Signs:
- 📌 Beck's Triad: 3 D's - Distant/Muffled heart sounds, Distended jugular veins (↑ JVP), Decreased arterial pressure (Hypotension).
- Pulsus paradoxus: Inspiratory ↓ SBP >10 mmHg.
- Tachycardia, dyspnea.
- Diagnosis:
- Echocardiography (Gold Standard):
⭐ Right atrial diastolic collapse is the earliest and most sensitive echocardiographic sign of cardiac tamponade.
- Also: RV diastolic collapse, swinging heart, plethoric IVC (no inspiratory collapse).
- ECG: Low voltage QRS complexes, electrical alternans.
- CXR: May show enlarged, globular heart ("water bottle sign") with large effusions.
- Echocardiography (Gold Standard):
- Management:
- Urgent pericardiocentesis (therapeutic & diagnostic).
- IV fluids (temporizing).

Acute Pericarditis - Heart's Fiery Rub
- Pericardial inflammation; often idiopathic/viral (Coxsackie B).
- Triad: Pleuritic/postural chest pain (relieved sitting up), pericardial friction rub, ECG changes.
- ECG Stages (📌 P-R-E-S-T Mnemonic):
- PR depression (except aVR/V1).
- Reciprocal ST depression (aVR/V1).
- Elevation of ST segments (widespread, concave).
- ST normalization.
- T wave inversion.
- Dx: ECG, Echo (effusion?), ↑ESR/CRP. CXR often normal.
- Rx: NSAIDs (Ibuprofen 600-800mg TID) + Colchicine (0.5-0.6mg BID x 3mo) to ↓ recurrence. Steroids if refractory.
- ⭐
Widespread concave ST elevation and PR segment depression (except in aVR, V1 where PR elevation and ST depression may be seen) are hallmark ECG findings in acute pericarditis.
oka
Constrictive Pericarditis - Heart's Rigid Cage
Fibrotic, calcified pericardium restricts diastolic filling.
- Etiology: TB (India), post-viral, post-surgery, radiation.
- Clinical Signs: RHF symptoms, pericardial knock, 📌 Kussmaul's sign (↑JVP on inspiration; K in Konstriction), Friedreich's sign.
- Investigations:
- CXR: Calcification.
- Echo: Thick pericardium, septal bounce, resp. variation.
- CT/MRI: Pericardial thickness >4mm.
- Cath: Equalized diastolic pressures (within 5 mmHg), "dip and plateau" sign.
- Treatment: Pericardiectomy.
⭐ In India, tuberculosis is a leading cause of constrictive pericarditis, often presenting with significant pericardial calcification visible on CXR or CT.
Table: CP vs. RCM
| Feature | Constrictive Pericarditis (CP) | Restrictive Cardiomyopathy (RCM) |
|---|---|---|
| Pericardium | Thick, calcified | Normal |
| Myocardium | Normal | Stiff, infiltrated |
| Pericardial Thick. | >4mm | Normal |
| Atrial Size | Mildly ↑ / Normal | Markedly ↑ |
| BNP | Mildly ↑ / Normal | Markedly ↑ |
| Septal Bounce | Present | Absent |
| Diastolic Pressures | Equalized | LVEDP > RVEDP (>5mmHg) |
High‑Yield Points - ⚡ Biggest Takeaways
- Constrictive Pericarditis: Features pericardial calcification, Kussmaul's sign, and diastolic septal bounce (Echo/MRI).
- Cardiac Tamponade: Presents with Beck's triad, pulsus paradoxus; Echo shows diastolic RV/RA collapse.
- Pericardial Effusion: Shows "water-bottle" heart (CXR), electrical alternans (ECG), and swinging heart (Echo).
- Acute Pericarditis: Diagnosed by friction rub, diffuse ST elevation, and PR depression on ECG.
- MRI/CT: Best for pericardial thickness, inflammation, cysts, and masses.
- Pericardial Cysts: Typically benign, most common at the right cardiophrenic angle.
Continue reading on Oncourse
Sign up for free to access the full lesson, plus unlimited questions, flashcards, AI-powered notes, and more.
CONTINUE READING — FREEor get the app