What causes a slow heart rate?

Meds/conduction abnl: Heart rate can be slowed by medications (beta blockers, nondihydropyridine calcium blockers, digoxin), or natural vs acquired abnormalities of conduction (age/thyroid abnormalities/enhanced vagal tone/hypoxemia/sleep apnea/myocardial fibrosis or scarring from infiltrative processes or mi, congenital transmission such as offspring of lupus patients. Eval shd focus on stability of rate/symptoms.

Possibly normal: Well conditioned athletes will have slow heart rates at rest. Other causes could be genetic conditions, medications, and some heart diseases or infections. See your primary physician to get the work up started with a thorough history and physical examination. Call 911 if you have severe dizziness, passing out, chest pain, or weakness.