Electrical Activity Of Heart Part 4

Question 1

What causes the auxiliary (emergency) pacemaker function of the AV node keeps the ventricles beating, although at an abnormally LOW rate?

Answer 1

Sick sinus syndrome

Question 2

What form of sick sinus syndrome causes sinus arrest, in which SA node completely fails to form action potentials?

Answer 2

Extreme form

Question 3

What form of sick sinus syndrome causes sluggish depolarization of the SA node pacemaker cells which leads to an abnormally LOW intrinsic heart rate?

Answer 3

Less extreme form

Question 4

What form of sick sinus syndrome causes insufficient increase in heart rate during exercise?

Answer 4

Less extreme form

Question 5

What can the following treat?
Cholinergic muscarinic antagonist drugs- atropine
Beta-adrenergic agonist drugs- isopronenlol
Artificial cardiac pacemaker

Answer 5

Sick sinus syndrome

Question 6

Which tachycardia is caused by abnormally rapid depolarization of SA node pacemaker cells?

Answer 6

Sinus tachycardia

Question 7

Which tachycardia originates from an ECTOPIC pacemaker within the atria?

Answer 7

Atrial tachycardia

Question 8

What is an extremely rapid atrial tachycardia?

Answer 8

Atrial flutter

Question 9

What is it called when atrial contraction become so rapid that they lose synchrony?

Answer 9

Atrial fibrillation

Question 10

What is it called when there is no effective, coordinated contraction, and no blood is pumped?

Answer 10

Atrial fibrillation

Question 11

What type of contractions are frequent, but irregularly spaced?

Answer 11

Ventricular contractions

Question 12

Which tachycardia originates from ECTOPIC pacemakers within the AV node or first part of the AV bundle?

Answer 12

Junctional tachycardia

Question 13

Which tachycardia is a collective term that encompasses sinus tachycardia, atrial tachycardia, and junctional tachycardia?

Answer 13

Supra-ventricular tachycardia

Question 14

Which tachycardia originated from the ECTOPIC pacemakers within the ventricles?

Answer 14

Ventricular tachycardia

Question 15

Which tachycardia is when the ventricles do not relax long enough between contractions for adequate filling?

Answer 15

Ventricular tachycardia

Question 16

What is it called when each tiny region of the ventricular wall contacts and relaxes at random in response to action potentials that propagate randomly and continuously throughout the ventricles?

Answer 16

Ventricular fibrillation

Question 17

What is synonymous with sudden cardiac death and can only be reversed by electrical defibrillation?

Answer 17

Ventricular fibrillation

Question 18

What degree of AV node block is:
Complete block of AV node?

Answer 18

3rd-degree

Question 19

What degree of AV node block is:
Av nodes transmits some atrial action potentials but not all of them

Answer 19

2nd-degree

Question 20

Strong ___________ activity can create or exaggerate 2nd-degree AV node block because ____________ activity increases the refractory period of the AV node cells

Answer 20

Parasympathetic

Question 21

2nd degree or 3rd degree AV node block often involves the eclectical phenomenon known as?

Answer 21

Decremental conduction

Question 22

What refers to the fading and eventual stoppage of a cardiac action potential in a slowly conducting region?

Answer 22

Decremental conduction

Question 23

What degree of AV node block is:
Every atrial action potential is transmitted to the ventricles

Answer 23

1st degree

Question 24

What degree of AV node block is:
Actio potential propagates more slowly than normal
Behavioral state influences the amount by which AV delay is prolonged because parasympathetic activity decreases the velocity of AV node conduction

Answer 24

1st degree