II. Pathophysiology
- Normal pattern in healthy adults and athletes
- Baseline Bradycardia suggests physical conditioning
- Other causes of Sinus Bradycardia
- See Drug Induced Bradycardia
- Hypothermia
- Severe infection
- Jaundice
- Carotid Sinus Hypersensitivity
- Tight shirt collar
- Excessive parasympathetic stimulation
- Acute inferior wall Myocardial Infarction
- Decreased sympathetic stimulation (medications)
III. Diagnostics: EKG Findings
- Regular rhythm with rate at <50 to 60 beats per minute
- Normal and consistent P-wave morphology
- Normal PR-Interval duration
IV. Differential Diagnosis
- See Bradycardia
V. Management
- Usually physiologic and requires no treatment
- If hemodynamically unstable, see Unstable Bradycardia