Chapter 17 Flashcards

1
Q

What are the three parts of an action potential?

A
  1. Resting when the membrane is polarized (+ on the outside and - on the inside)
  2. Depolarization (+ on the inside and - on the outside)
  3. Repolarization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the major charge carriers in cardiac muscle cells?

A

Sodium, Potassium, Calcium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 5 phases of an action potential? What is happening in each?

A

0: rapid depolarization, Na+ in
1: early repolarization, K+, Cl- out
2: the plateau, Ca+ in, K+ out
3: rapid repolarization, K+ out
4: the resting membrane, K+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is automaticity?

A
  • Spontaneously initiate an action potential

- back up system for the health to start up an action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain SA node, AC node, and Purkinjes.

A

SA node: 60-100/ where rhythmic impulse is generated
AV node: 40-60/ impulse from atria is delayed
Purkinjes: 20-40/ conducts impulse to all parts of the ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is excitability?

A

Responding to an impulse and then generating its own action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is conductivity?

A

To conduct impulses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is remissibility?

A

Having a beat that is regular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain the pathway in the electrical system of the heart.

A

Sa node/ Bachmann’s bundle > internodal tracts > AV node > bundle of his > left & right bundle branch > perkinjes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain the Depolarization and repolarization of an ECG.

A
  • SA node-> AV node = atrial depolarization
  • atrial depolarization= P wave (induces atrial systole)
  • AP spread through bundle of his, bundle branches, punkinjes =ventricular depolarization
  • ventricular depolarization= QRS (induces ventricular systole)
  • ventricular diastole is induced when AP passes out of ventricles
  • ventricular repolarization = T wave
  • purkinje repolarization= U wave
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does fibrillation mean?

A

Disorganized current flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is sinus bradycardia? Manifestations?

A
  • <60
  • Normal/ ischemia (restriction of blood supple, decreased oxygenation
  • S&S of decreased perfusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is sinus tachycardia? Manifestations?

A
  • > or equal to 100
  • normal with exertion/ fever
  • ischemia, hypoxemia
  • increased myocardial workload, decreases coronary artery perfusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is sinus arrest? Manifestions?

A
  • Heart stops and starts up again
  • not common and not forever (short pause)
  • ischemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is sick sinus arrest?

A
  • sinus arrest occurs frequently

- may need a pacemaker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is premature atrial complexes (PAC)?

A
  • Early depolarization occurring in the atria (not SA node)
  • common
  • May happen when drinking coffee- little jolt, extra beat
17
Q

What is supra ventricular tachycardia (PSVT)?

A

P happens once in a while, S is above the ventricle

  • really fast for various reasons
  • 140-240/min, sudden onset and cessation
  • Due to ischemia, reentry (Wolff-Parkinson-White Syndrome)
18
Q

What is atrial flutter?

A
  • Ectopic atrial tachycardia 240-450/min d/t reentry
  • Atrium contact 4 times before the ventricle contacts (but people survive as long as the ventricle continues to contract)
19
Q

What is atrial fibrillation?

A
  • Chaotic depolarization with only occasional contraction
  • Paroxysmal/ chronic d/t MI, HF
  • Atria is vibrating, so it is not contracting so blood is not going to the ventricles (blood is being pushed through but not by contraction.. it is trickling down)
  • Cardiac output is down by 30%
20
Q

What is AV conduction Arrhythmias?

A

Blocks: AV node, bundle of His, bundle branch issue

1st degree atrioventricular block is consistent

21
Q

Explain 2nd degree AV blocks.

A

Mobitz type 1/ Wenckebach

  • increasing PR until QRS drops
  • people can live with tired AV node (has a regular rhythm with a pause)

Mobitz type 2

  • occasional dropped QRS
  • PR stable
  • There is something wrong with the AV node
22
Q

Explain 3rd degree AV block.

A
  • Atria and ventricles are working but there is no electrical connection between the two (AV node stopped working)
  • Shows P and QRS wave but no connection
  • Firing at 40-60
23
Q

What is ventricular arrhythmias (Premature ventricular complexes, PVC)?

A
  • When you drink coffee (normal)
  • Had a heart attack (bad thing leading to ischemia)
  • d/t irritability (ischemia/necrosis)
24
Q

What is ventricular tachycardia?

A

-No cardiac output, arrest situation, lethal rhythm and leads to death

25
Q

What is ventricular fibrillation?

A

It is lethal and leads to death

26
Q

What is asystole?

A

-Lethal rhythm (flat line)

27
Q

What is happening in the heart during atrial fibrillation?

A
  1. quivering muscle
  2. poor emptying
  3. poor filling of the ventricle= decreased CO
28
Q

How will your patient present during atrial fibrillation?

A
  1. Tired (brain is not getting enough O2)
  2. Irregularly irregular HR
  3. pulse will be irregular and different strengths
  4. Low BP
  5. All other systems will show signs of decreased CO
29
Q

How many leads can be on an ECG (electrocardiogram)?

A

12 or 16

30
Q

What is a holter monitor? and what is other cardiac conduction diagnostics?

A
  • A monitor that is attached to a person while they’re performing their daily activities.
  • Exercise stress test and electophysiologic studies
31
Q

What are different treatments for conduction disorders?

A
  1. Pharmacology
  2. Electrical
    - cardioversion (pharmacological, physiologic, electrical)
    - defibrillation
    - pacemaker
  3. surgical
    - ablation, pacemaker, defibrillator