Brady arrythmias

Question 1

Causes and Pathophysiology of Brady Arrhythmias

Answer 1

High parasympathetic/vagal tone - imbalance, athlete, reflex
ß blockers, cholinergics, some Ca channel blockers
Age = sick sinus syndrome
Damage to the SA node (Sx or infarct)
Conduction problem through heart

Question 2

Describe clinical syndromes of various Brady Arrhythmias

Answer 2

Sick sinus syndrome: can’t raise HR; sometimes sudden tachy (A fib.) episodes then return to brady
AV node blocks:
1st: each P wave leads to a QRS, just >200ms. Long PR
2nd:
-Mobitz I (Wenkebach): PR interval increases, then drop a QRS.
-Mobitz II: Just drops a QRS, same length otherwise, constant ratio
3rd: disjointed P and QRS. P-P constant, R-R constant - escape rhythm

Question 3

Symptoms of Brady Arrhythmias

Answer 3

SSS: fainting after tachy episode
3rd: fainting, death

Question 4

Signs and Physical findings of Brady Arrhythmias

Answer 4

Low/Unable to raise HR

Dropped carotid pulse but no dropped JVP

Question 5

Key lab tests and findings of Brady Arrhythmias

Answer 5

EKG: see the disparity b/w P waves and QRS. The wider and more bizarre the waves, the deeper into the heart it is.

Question 6

Tx of Brady Arrhythmias

Answer 6

Wenkebach: anti-cholinergic
Sx: pacemaker

Question 7

Pacemaker details of Brady Arrhythmias

Answer 7

4 letters tell what type of pacemaker:
1st = CHAMBER(s) PACED (A, V, D)
2nd = CHAMBER(s) SENSED (A, V, D)
3rd = ACTIVITY in response to sensing (I or T)
4th = if able to sense patient’s activity -↑rate (R)