ECG Hallucinations: When Irregular Is Not Atrial Fibrillation

ECG Weekly Workout with Dr. Amal Mattu

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HPI

A 69-year-old man presents with chest pain. His ECG is interpreted by the computer as atrial fibrillation, a diagnosis that could significantly alter his evaluation and long-term management. The rhythm is irregular, P waves are difficult to appreciate in lead II, and the automated interpretation seems plausible at first glance. But a closer look reveals a different story.

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

1. 1. What rhythm features must be present before diagnosing atrial fibrillation?
   2. What lead is particularly useful when P waves are difficult to identify?
   3. What rhythms commonly mimic atrial fibrillation?
   4. Why does overdiagnosing atrial fibrillation have potentially significant consequences?