Three More ECG Pitfalls That Punish Anchoring Bias

UMEM Potpourri ECG Cases with Dr. Amal Mattu

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HPI

A 51-year-old man with lung cancer presents with shortness of breath and tachycardia. The arrival ECG shows an S1Q3 pattern and seems to support a familiar diagnosis that would normally trigger immediate anticoagulation:

Before watching this week’s workout, review the arrival ECG carefully and consider:

1. 1. What ECG combination should make you think pericardial effusion before committing to a PE pathway?
   2. Why is it dangerous to rely on electrical alternans to “rule in” tamponade physiology?
   3. What is the worst-case consequence of empiric anticoagulation or thrombolytics if the true diagnosis is pericardial effusion?