How should Dressler syndrome presenting 2 weeks to 3 months after myocardial infarction with pleuritic chest pain, low‑grade fever, and a pericardial friction rub be diagnosed and managed?

Dressler Syndrome: Diagnosis and Management

Immediate Diagnostic Approach

Diagnose Dressler syndrome when pleuritic chest pain occurs 2 weeks to 3 months post-MI plus at least one of: pericardial friction rub, ECG changes (PR depression or diffuse ST elevation), or new/growing pericardial effusion on echocardiography. 1

Clinical Presentation to Confirm

• Sharp, pleuritic chest pain that worsens with inspiration and improves when sitting forward—this postural and respiratory relationship distinguishes it from recurrent ischemic pain 2
• Low-grade fever without alternative explanation is a cardinal feature 2
• Pericardial friction rub on auscultation (though may be absent) 2
• Symptoms typically appear 1-2 weeks to several months after MI, representing an immune-mediated response to pericardial injury 1

Mandatory Diagnostic Work-Up

• Transthoracic echocardiography is mandatory to detect pericardial effusion and assess for tamponade 2
• ECG may show persistent ST-segment elevation with upright T waves, though often masked by infarction-related changes 2
• Elevated C-reactive protein confirms ongoing inflammation and is essential for diagnosis 2
• Chest imaging (ultrasound or radiography) to assess for pleural effusion 2

Critical Red Flag

If pericardial effusion exceeds 10 mm thickness, urgent investigation for subacute ventricular rupture is mandatory—two-thirds of such patients may progress to tamponade or free-wall rupture 2, 3. Hospital admission is required to monitor for tamponade and adjust treatment 2.

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First-Line Treatment

Treat with high-dose aspirin (500-1,000 mg every 6-8 hours) plus colchicine (0.5-0.6 mg once or twice daily) for 3 months. 1, 4

Aspirin Dosing Details

• Total daily dose: 1.5-4 g/day divided every 6-8 hours 1, 4
• Aspirin is the preferred NSAID because it improves coronary flow and provides antiplatelet effects at these doses 2
• Continue until symptoms improve, then taper gradually (decrease by 250-500 mg every 1-2 weeks) 4

Colchicine Dosing Details

• 0.5-0.6 mg twice daily if weight ≥70 kg 1, 4
• 0.5-0.6 mg once daily if weight <70 kg 1, 4
• Duration: 3 months minimum (some guidelines suggest 6 months for post-cardiac injury syndromes) 1, 4
• Adjust dosing in stage 4-5 kidney disease, severe hepatic impairment, or with concomitant P-glycoprotein/CYP3A4 inhibitors 1
• Colchicine reduces recurrence rates by approximately 50% 4

Rationale for Combination Therapy

The combination of aspirin plus colchicine is based on RCTs of colchicine performed on a background of high-dose aspirin therapy, though dedicated RCTs specifically for post-MI pericarditis are lacking due to its rarity (0.1-0.5% incidence in the modern reperfusion era) 1

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Medications to Avoid

Do NOT use glucocorticoids or NSAIDs other than aspirin (except ibuprofen) as first-line therapy—they are potentially harmful due to increased risk of recurrent MI, impaired myocardial healing, and risk of ventricular rupture 1, 2. Corticosteroids should be reserved only for refractory cases with extreme caution 2.

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Management of Refractory Cases

If symptoms persist despite aspirin plus colchicine:

• Short-term corticosteroid therapy (3-6 months) may be used with caution, given the risk of delayed myocardial healing 4, 2
• Intrapericardial triamcinolone (300 mg/m²) via pericardiocentesis is an alternative for refractory cases 4, 2
• Taper one drug at a time before gradually discontinuing colchicine over several months 4

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Monitoring and Follow-Up

• Serial CRP measurements can guide treatment duration and assess therapeutic response 2
• Repeat echocardiography if clinical deterioration or concern for tamponade develops 2
• Hospital admission is mandatory for effusions >10 mm to observe for tamponade and adjust treatment 2

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Prognosis

• Despite association with larger infarct size, in-hospital and 1-year mortality rates are comparable between patients with and without post-MI pericarditis 2
• Rare but serious complications include hemopericardium, cardiac tamponade (<2% of cases), and constrictive pericarditis (approximately 3% of cases) 2
• The condition typically follows a favorable prognosis with appropriate anti-inflammatory therapy 5

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Common Pitfalls to Avoid

• Do not misinterpret pericarditic chest pain as recurrent MI or unstable angina—focus on sharp quality, postural changes, and respiratory variation in the history 2
• Do not dismiss pericardial effusions >10 mm—they require prompt investigation for possible subacute ventricular rupture 2
• Do not use routine high-dose aspirin or colchicine for asymptomatic pericardial effusions—treatment is indicated only for symptomatic patients 1
• Anticoagulant use (particularly warfarin) significantly increases bleeding risk into the pericardial space 3