- All atrial impulses are transmitted to the ventricles, but the conduction times are prolonged → ↑ PR interval
- lengthens the delay between atrial and ventricular depolarization
- prolonged PR interval that is consistently prolonged by the same amount in every cycle
-
0.2 secs, i.e. > 1 large box
-
- In most patients with 1˚ AVB, the slow conduction is localized to the AV node. Although less common, 1˚ AV block may be distal/infranodal, but still tends to be asymptomatic.[^fogoros]
