Overview
Definition
A delay in conduction from the atria to the ventricles, but all atrial impulses are eventually conducted.
Epidemiology
Common, often a benign incidental finding in young athletes or the elderly.
Etiology & Risk Factors
- High vagal tone (athletes)
- Medications (AV nodal blockers)
- Ischemia
- Lyme disease
Clinical Symptoms
- Almost always asymptomatic
Clinical Approach
Diagnosis
- ECG: Prolonged PR interval (> 200 ms or > 5 small boxes), but every P wave is followed by a QRS complex
Management
- No treatment required
- Monitor for progression if on AV nodal blocking drugs
Complications
- Usually none. Low risk of progressing to higher-degree blocks.