Which of the following is NOT typically considered part of the differential diagnosis for bradycardia?

• A. Arrhythmia
• B. Acute coronary syndrome
• C. Migraine
• D. Hypoxia

Answer: (C)

Bradycardia invites evaluation for factors that slow the heart’s electrical activity, whether by intrinsic conduction disease, increased vagal tone, metabolic or ischemic stress, or drug effects. Migraine isn’t a typical driver of a slow heart rate; it’s a neurologic condition whose main manifestations are headaches and neurologic symptoms, not a primary cause of bradycardia in the differential. In contrast, arrhythmias directly involve the heart’s rhythm, acute coronary syndrome can impair conduction or overall myocardial function, and hypoxia can trigger reflex or metabolic changes that lower heart rate. So, while migraines can have autonomic symptoms, they do not usually belong in the bradycardia differential.