First Degree AV Block
This is the most common conduction disturbance. It occurs in both healthy and diseased hearts.
First degree AV block can be due to:
- inferior MI,
- digitalis toxicity
- increased vagal tone
- acute rheumatic fever
Interventions include treating the underlying cause and observing for progression to a more advanced AV block.
In first degree AV block, the P-R interval is: