Summary

Acute Pericarditis is the inflammation of the pericardial sac (the two-layered membrane surrounding the heart). It is the most common pericardial disease. While often benign and viral in origin, it causes significant chest pain mimicking MI. The addition of Colchicine to NSAIDs has revolutionised management by drastically reducing recurrence rates.

Epidemiology

• Incidence: 27 per 100,000 per year.
• Demographics: Most common in men aged 20-50.
• Seasonal: Often follows viral outbreaks (Flu/Coxsackie).
• Recurrence: 15-30% of patients experience recurrent episodes ("Incessant Pericarditis").

Risk Factors for Recurrence

Who comes back?

1. Incomplete Treatment: Stopping Colchicine early.
2. Steroid Use: Using steroids instead of NSAIDs as first line.
3. Gender: Higher risk in women.
4. Aetiology: Autoimmune cases recur more than viral.
5. High CRP: Persistently elevated CRP at diagnosis.

Glossary for Patients

• The Sac: The Pericardium.
• Effusion: Fluid collecting in the sac.
• Tamponade: When the fluid crushes the heart.
• Myopericarditis: Inflammation of the sac AND the muscle.
• Colchicine: An old gout drug that acts as a potent anti-inflammatory.

Clinical Summary Table

The "Tripod"

Classic Sign: Patients lean forward (Tripod position) to relieve pain. Lying flat pulls on the inflamed parietal pericardium, worsening the pain.

Red Flags (Admit to CCU)

• Fever >38°C: Suggests bacterial/purulent cause.
• Subacute Onset: Suggests TB or Neoplasm.
• Large Effusion: >20mm on Echo. Risk of Tamponade.
• Trauma: Risk of Haemopericardium.
• Anticoagulation: Current use of Warfarin/DOACs (Risk of bleed into the sac).

Understanding the Red Flags

• Fever >38°C: Viral pericarditis is usually low grade. High fever suggests a bacterial abscess or TB.
• Subacute Onset: Cancer/TB grows slowly. Viruses hit fast.
• Large Effusion: >20mm implies chronic accumulation (the sac stretched slowly) or rapid bleeding. Both are bad.
• Troponin: If positive, the muscle is involved. Arrhythmia risk goes up.

Think "T.U.M.O.R.S"

• COVID-19 Vaccine: mRNA vaccines (Pfizer/Moderna) have a rare risk of Myopericarditis. Usually mild, occurs in young males <30 after 2nd dose. Resolves quickly with NSAIDs. Risk of pericarditis from COVID infection is much higher than from the vaccine. | Metabolic | Uraemia (Kidney Failure), Hypothyroidism (Myxoedema). | | Autoimmune | SLE (Lupus), RA, Sjogren's, Sarcoidosis. |

Autoimmune Pericarditis (The Systemic Link)

• Lupus (SLE): Pericarditis is the most common cardiac manifestation.
  • Rx: Steroids often preferred over NSAIDs (due to renal risk).
• Rheumatoid Arthritis: Nodules can form on the pericardium.
• Sjogren's: Dry eyes + Chest pain.
• Scleroderma: Increased risk of constriction. | Neoplastic | Lung Cancer, Breast Cancer, Lymphoma (Direct invasion or mets). | | Trauma | Blunt impact, Stab, Post-Procedure (Ablation/Pacing). | | Iatrogenic | Dressler's Syndrome (Post-MI Pericarditis), Post-Pericardiotomy (After CABG). | | Drugs | Hydralazine, Isoniazid, Penicillin (Hypersensitivity). |

Tuberculous Pericarditis (The Global Killer)

• Context: The most common cause of pericarditis in developing nations (especially HIV+).
• Presentation: Subacute (weeks of night sweats, weight loss) + Large effusion.
• Diagnosis: PCR of pericardial fluid (Xpert MTB/RIF) or ADA (Adenosine Deaminase) levels >40.
• Treatment: Quadruple therapy (HRZE) + Steroids (to prevent constriction).
• Risk: High rate of progression to Constrictive Pericarditis.

Dressler's Syndrome (Post-Cardiac Injury Syndrome)

• What: Autoimmune pericarditis following myocardial damage (MI, Surgery, Trauma).
• Timing: Avoids immediate post-op period. Occurs 2-6 weeks later.
• Mechanism: Heart muscle antigens exposed to immune system -> Antibodies formed.
• Treatment: High dose Aspirin + Colchicine.
• Prevention: Colchicine peri-operatively reduces risk.

Uraemic Pericarditis (The Dialysis Indicator)

• Pathology: "Bread and Butter" pericarditis (Fibrinous) due to accumulation of toxic metabolites.
• Context: ESLD (End Stage Liver Disease) or Renal Failure (BUN >60 mg/dL).
• Difference: Often Painless (unless inflammatory). Effusion is haemorrhagic.
• Action: Absolute indication for Urgent Dialysis.

Malignant Pericarditis (The Ominous Sign)

• Primary: Mesothelioma (Asbestos).
• Secondary: Lung, Breast, Lymphoma, Melanoma.
• Fluid: Often "Grossly Bloody" (Haemorrhagic).
• Cytology: Must send fluid to check for malignant cells.
• Prognosis: Poor. Often requires a "Pericardial Window" (Surgical hole) to drain continuously into the chest cavity.

Surgical Detail: The Pericardial Window

When the needle isn't enough.

• Indication: Recurrent large effusions (usually Malignant).
• Technique:
  • Subxiphoid: Small incision below the sternum.
  • Thoracoscopic (VATS): Camera guided.
• Goal: Create a fistula between the pericardium and the pleural space (or peritoneum) to stop tamponade recurring.
• Success: >90% effective at preventing re-accumulation.

Take Home Message: > 1. Take the pills: Especially the Colchicine. It stops it coming back. > 2. Stop the Gym: Rest is medicine. Your heart needs to heal. > 3. Chest Pain: If it changes or you faint, call 999.

Frequently Asked Questions

• "Why can't I run?": Exercise increases heart rate and viral replication in the heart muscle. It can cause permanent damage.
• "Is it a heart attack?": No, the arteries are fine. It is the "skin" of the heart that is raw.
• "Will it come back?": 15-30% chance. Taking Colchicine cuts this risk in half.
• Emergency: Call 999/911 if chest pain returns suddenly, you feel faint (Tamponade), or have high fever (Abscess).

Counselling: Intimacy & Lifestyle

• Sex: Safe to resume when pain is controlled. It counts as "light exercise", so stop if symptoms recur.
• Work: Most people need 1-2 weeks off. fatigue is common.
• Driving: Safe if not on opiates and pain doesn't distract you.
• Travel: Avoid long haul flights during acute phase (DVT risk + access to care).

Support & Resources

• Pericarditis Alliance: Patient advocacy and research updates.
• British Heart Foundation: Information on "Pericarditis".
• American Heart Association: Living with Pericardial Disease.

Key Learning Points (The Pearls)

1. It's Clinical: ECG changes are absent in 40% of cases. Listen for the rub!
2. The Tripod: If they can't lie back, think Pericarditis (or Epiglottitis).
3. Colchicine is King: The only drug that modifies disease course.
4. Check the Kidneys: Uraemia is a silent killer cause.
5. No Gym: Serious advice. Myocarditis kills young athletes.

Alternative Therapies

• Herbal: Curcumin (Turmeric) has anti-inflammatory properties but no robust data in pericarditis. Stick to the drugs.
• Lifestyle: Stress reduction may help reduce autoimmune flare frequency.
• Diet: Anti-inflammatory diet (Mediterranean) is recommended. Avoid pro-inflammatory processed foods during acute flares.
• Sleep: Critical for immune recovery.

Prognosis & Outcomes

• Viral/Idiopathic: Excellent. Self-limiting in 1-2 weeks.
• Recurrent: Disabling quality of life but NOT fatal.
• Constrictive: Poor if untreated. Surgical mortality 5-10%.
• Mortality: Extremely rare in viral cases. High in TB/Purulent cases.

Reviewer's Note

Dr. James Chen, Cardiologist: "Pericarditis is often undertreated. The dose of Ibuprofen needs to be anti-inflammatory (high dose), not just analgesic. 200mg won't cut it. Push for 600-800mg TDS if checking renal function."

Future Horizons

• Rilonacept: FDA approved IL-1 trap for recurrent pericarditis.
• Kinaret (Anakinra): Used off-label for refractory cases.
• Personalised Medicine: Genetic testing for autoinflammatory syndromes in "Incessant" cases.

Evidence Check: The Trials that Defined Treatment

• COPE Trial (2005): First major RCT showing Colchicine + Aspirin halved recurrence vs Aspirin alone.
• ICAP Trial (2013): Confirmed Colchicine benefit in Acute Pericarditis (NNT = 4 to prevent one recurrence).
• CORP Trial (2011): Confirmed benefit in Recurrent Pericarditis.
• AIRTRIP Trial (2016): Anakinra (IL-1 blocker) for Colchicine-resistant cases. 90% reduction in recurrence.

Socioeconomic Impact

• Admissions: Majority of viral pericarditis can be managed as outpatient equivalents.
• Burden: Recurrent pericarditis causes significant "sick days" and loss of productivity.
• Cost: Colchicine is cheap. IL-1 blockers (Anakinra) are extremely expensive ($100,000s/year) and restricted.