A first-degree AV node block occurs when conduction through the AV node is slowed, thus delaying the time it takes for the action potential to travel from the SA node, through the AV node, and to the ...
In second-degree AV nodal block (a.k.a. Wenckebach block or Mobitz Type I AV block), varying failure of conduction through the AV node occurs such that some P waves may not be followed by a QRS ...