Dressler Syndrome: Clinical Presentation, Diagnosis, and Management
Overview
Dressler syndrome is a late post-myocardial infarction pericarditis that should be treated with aspirin (500–1,000 mg every 6–8 hours, total 1.5–4 g/day) plus colchicine (0.5–0.6 mg once or twice daily for 3 months) as first-line therapy. 1, 2
Epidemiology and Pathophysiology
Incidence is now extremely rare (< 1% of MI patients, some sources cite < 0.5%) in the primary PCI era, occurring only after larger infarcts, delayed reperfusion, or failed reperfusion. 1, 2, 3
Timing: Develops 1–2 weeks to several months after myocardial infarction, with the latent period distinguishing it from early post-infarction pericarditis (which occurs days 2–3). 1, 2, 3
Autoimmune mechanism: Triggered by myocardial necrosis releasing antigenic material, leading to antiheart antibody formation and immune-mediated inflammation. 2, 3
Clinical Presentation: Key Features to Identify
Cardinal Symptoms
Sharp, pleuritic chest pain that worsens with inspiration and improves when sitting forward—this postural and respiratory relationship is critical for differentiating from recurrent ischemia. 2
Fever without alternative explanation is a hallmark feature. 2
Pericardial friction rub on auscultation (though may be absent). 2
Pleuritic chest pain and pleural friction rubs may occur due to simultaneous pleuro-pericardial inflammation. 2
Diagnostic Pitfall
- Do not misinterpret pericarditic chest pain as recurrent MI or unstable angina—focus on sharp quality, postural change, and respiratory variation during history-taking. 2
Diagnostic Approach: Specific Work-Up
Diagnostic Criteria
Diagnosis requires at least 2 of the following 5 criteria: 2
- Fever without other cause
- Pericarditic or pleuritic chest pain
- Pericardial or pleural rubs
- Pericardial effusion
- Pleural effusion with elevated C-reactive protein
Essential Investigations
Transthoracic echocardiography is mandatory to detect pericardial effusion and evaluate for tamponade. 2
- Critical threshold: Effusion > 10 mm mandates urgent evaluation for sub-acute ventricular rupture, as two-thirds may progress to tamponade or free-wall rupture. 2
ECG findings: Often shows persistent ST-segment elevation with upright T waves, but these are frequently masked by primary infarction-related changes. 2
Elevated C-reactive protein confirms ongoing inflammation and is essential for diagnosis. 2
Thoracic ultrasound or chest radiography to assess for pleural effusion and pulmonary infiltrates. 2
Pericardial fluid characteristics (if sampled): Exudative with hemorrhagic appearance common, elevated protein and inflammatory markers. 3
Management Algorithm
First-Line Therapy (All Patients)
Aspirin plus colchicine is the standard regimen: 1, 2
Aspirin: 500–1,000 mg every 6–8 hours (total daily dose 1.5–4 g/day)
- Aspirin is preferred because it improves coronary flow and provides antiplatelet effects at these doses. 2
Colchicine: 0.5–0.6 mg once or twice daily for 3 months
Treatment Duration and Tapering
Continue therapy for several weeks to months, even after effusion disappears. 1
Taper gradually: Decrease aspirin by 250–500 mg every 1–2 weeks, taper one drug at a time, then gradually discontinue colchicine over several months in difficult cases. 1
Serial CRP measurements can guide treatment duration and assess therapeutic response. 2
Medications to Avoid
Other NSAIDs (except ibuprofen) should be avoided because they may thin the infarct zone. 2
- Ibuprofen is acceptable only when aspirin cannot be used, as it also enhances coronary flow. 2
Systemic corticosteroids should be avoided or reserved for refractory cases due to risk of delayed myocardial healing. 1, 2
Management of Refractory Cases
For persistent symptoms despite first-line therapy: Short-term corticosteroid therapy (3–6 months) may be used with caution. 1, 2
Alternative: Pericardiocentesis with intrapericardial triamcinolone (300 mg/m²). 1, 2
Critical Clinical Caveats
Hospitalization Criteria
- Mandatory hospital admission for patients with pericardial effusion > 10 mm to monitor for tamponade, establish differential diagnosis, and adjust treatment. 1, 2
Complications (Rare but Serious)
- Hemopericardium and cardiac tamponade occur in < 2% of cases. 2
- Constrictive pericarditis develops in approximately 3% of cases. 2
Prognosis
- In-hospital and 1-year mortality rates are comparable between patients with and without post-MI pericarditis, despite association with larger infarct size. 2