E.C.G. Course – VII AV blocks Dr. Michael Kassirer ”Dept. Internal Medicine ”D Tel-Aviv Medical center
:Objectives By the end of lesson 7 the student will:
Know how to diagnose 1, 2nd degree (type I and II), and 3rd degree AV blocks
Understand the difference between high and low AV blocks and their clinical implication.
Understand the difference between wide and narrow QRS complex, regarding AV blocks.
1° Av Block
2° Av Block (Mobitz I) = Wenckebach
2° ( Av Block (Mobitz II Second degree AV block – Mobitz type 2
Normal P>R
N/A
P>R
No of Ps > No of QRS PR interval does not prolongs from beat to beat
3° AV Block (Complete (AVB
AV dissociation QRS narrow or wide (= slower HR)
High vs. Low degree AVB 1° AVB
2° AVB Mobitz I
Bradycardia unlikely
2° AVB Mobitz I 3° AVB
Bradycardia possible
(Pacemaker (STBY / permanent
Bi-Fascicular block
Tri-Fascicular block
1º AV block RBBB Left anterior hemiblock