Third Degree Atrioventricular (AV) block

Question 1

Third-degree (complete) AV block involves

Answer 1

a total lack of communication between the atria and ventricles due to AV node dysfunction.

Question 2

Third degrees AV block can result from

Answer 2

ischemia, infiltrative disease, infection, or age related fibrosis with cellular degeneration.

Question 3

The slow ventricular rate in third degree AV block leads to reduced cardiac output, potentially causing

Answer 3

dyspnea, fatigue, lightheadedness, and syncope.

Question 4

The slow ventricular rate in third degree AV block leads to

Answer 4

reduced cardiac output

Question 5

Definitive management of third degree heart block requires placement of a

Answer 5

permanent pacemaker

Question 6

Discuss the pathophysiology of third degree AV block

Answer 6

because conduction signals from the atria cannot communicated with the ventricles, the intrinsic pacemaker of the His bundle or ventricles is triggered, resulting in a junctional or ventricular escape rhythm. On ECG, there is dissociation of P waves and QRS complexes, with P waves marching out at the intrinsic rate of the SA node and QRS complexes at the intrinsic rate of the His bundle or ventricles

Question 7

Discuss Third degree (complete) AV block

Answer 7

Third-degree (complete) AV block involves dysfunction of the AV node, resulting in total lack of communication between the atria and the ventricles. On ECG, there is dissociation of P waves and QRS complexes, with P waves marching out at the intrinsic rate of the SA node and QRS complexes at the intrinsic rate of the His bundle or ventricles (escape rhythm)

Question 8

Discuss the EKG of third degree heart block

Answer 8

Question 9

What infection is assocaited with third degree AV node block

Answer 9

Lyme Disease

Question 10

What inflammatory condition is associated with third degree heart block

Answer 10

Sarcoidosis