Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A. White- Human Physiology > Cardiac arrhythmas > Flashcards

Cardiac arrhythmas Flashcards

1
Q

Define Tachyardia

A

Fast heart rate (>100 beats/min)

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

What are some causes of Tachycardia?

A
  1. increased body temperature
  2. stimulation of the heart by the sympathetic nerves
  3. toxic conditions of the heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define Bradycardia

A

Slow heart rate (<60 beats/min)

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

What are some causes of bradycardia?

A
  • athletic heart
  • vagal stimulation (parasympathetic stimulation)
  • extremely sensitive carotid baroreceptors in carotid sinus syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What arrhythmia is present?

A

Atrial fibrillation

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

What arrhythmia is present?

A

Atrial paroxysmal tachycardia

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

What arrhythmia is present?

A

Atrial premature beat

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

What arrhythmia is present?

A

A-V nodal premature contraction

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

What arrhythmia is present?

A

Complete A-V block

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

What arrhythmia is present?

A

Partial intraventricular block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What arrhythmia is present?

A

First degree A-V heart block

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

What arrhythmia is present?

A

Second degree A-V block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What arrhythmia is present?

A

Sinoatrial nodal block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What arrhythmia is present?

A

Sinus bradycardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What arrhythmia is present?

A

Tachycardia

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

What arrhythmia is present?

A

Ventricular fibrillation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What arrhythmia is present?

A

ventricular paroxysmal tachycardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are some physiological results of endogenously mediated tachycardia?

A
  • heart rate increases
  • cardiac output increase
  • filling time is reduced but stroke volume does not fall
19
Q

What are som physiological results of pathologically mediated tachycardia?

A
  • heart rate increases
  • cardiac output decreases
20
Q

What are spillover signals?

A

Signals sent from the medullary respiratory center into the vasomotor center during inspiratory and expiratory respiratory signals

  • These signals alternately increase and decrease the number of impulses transmitted through sympathetic and vagus nerves through the heart
21
Q

What are the characteristics of a sinoatrial block?

A
  • sudden cessation of P waves
  • resultant standstill of atria
  • ventricles pick up a new rhythm, usually in the AV node
  • rate of QRS is slowed but not otherwise altered
22
Q

What would be some conditions that would cause an atrioventricular block?

A
  1. ischemia of AV node od Av bundle fibers through coronary insufficieny
  2. compression of AV bundle by scar tissue or calcified portions of the heart
  3. inflammation of the AV node or bundle
  4. extreme stimulation of the heart by the vagus nerves
23
Q

What are the two types of incomplete atrioventricular block?

A
  1. First-degree
  2. second-degree
24
Q

What characterizes a first-degree A-V block?

A

When P-R interval increases to greater than 0.20 sec. (normal is 0.16)

25
Q

What is the normal P-R time interval?

A

0.16 sec

26
Q

What characterizes a second-degre A-V block?

A
  • P-R interval increases to 0.25 to 0.45 sec
  • Atrial P wave is present but QRS-T wave may be missing, resulting in dropped beats of the ventricle
  • 2:1 rhythm or other variations may develop
27
Q

Periodic fainting spells due to a complete A-V block is referred to as what?

A

Stokes-Adam syndrome

28
Q

Patients will often faint due to a lack of blood to the brain until the ventricles escape because of what type of block?

A

A complete A-V block

29
Q

A partial intraventricular block is can be also referred to as what?

A

Electrical alternans

30
Q

What term refers to an alteration in the amplitude of P waves, QRS complexes, or T waves?

A

Electrical alternans

31
Q

Most premature contractions result from what?

A

Ectopic foci in the heart

32
Q

Name 2 of the 3 possible causes of ectopic foci.

A
  1. local areas of ischemia
  2. calcified plaques
  3. toxic irritation of the conduction system or nodes
33
Q

What does the term paroxysmal mean?

A

It means that the heart rate becomes rapid in paroxysms

34
Q

What are some characteristics of paroxysmal tachycardia?

A
  • paroxysms beigin suddenly and can last for seconds, minutes, hours, or longe
  • paroxysms end suddenly
  • pacemaker of the heart instantly shifts back to the sinus node
35
Q

What is the physiological basis behind fibrillation?

A

The normal ventricular depolarization waves die out because the heart muscle that has already contracted is in the refractory period and cannot respond to being stimulated by the existing depolarization waves

36
Q

What is fibrillation?

A

The twitching (usually slow) of individual muscle fibers in the atria or ventricles and also recently denervated skeletal muscle fibers.

37
Q

Fibrillation occurs as a reult of these?

A

Circus movements

38
Q

List 2 of the 3 conditions that cause the impulse to travel in around the circle (circus movements)?

A
  1. the pathway around the circle is too long
  2. the length of the pathway remains constant but the velocity of the conduction slows down
  3. the refractory period of the muscle might become greatly shortened
39
Q

What do circus movements occur if the pathway around the cirle is too long?

A

By the time to impulse returns to its starting point the originally stimulated muscle will no longer be in the refractory period and the impulse will continue around the circle again and again.

-Chareacteristic of dilated hearts

40
Q

Whay do circus movements occur when the length of the pathway remains constant but the velocity of the conduction slows down?

A

An increased amount of time will elaspe before the impulse returns to its original position. By this time, the originally stimulated muscle might be out of the refractory period, and the impulse can continue around the circle again and again.

-Characteristic of blockage of the Purkinje system, ischemia, or high potassium levels.

41
Q

Why do circus movements occur when the refractory period of the muscle is shortened?

A

With a shorter refrractory period the impulse could continue around the circle again and again.

  • May occur in reponse to drugs such as epinephrine or after repetitive electrical stimulation
42
Q

The atrial muscle fibers are seperated from the ventriculoar muscle fibers by the _______ _______ _______?

A

Cardiac fibrous skeleton

43
Q

True or False: ventricular and atrial fibrillation may occur seperate from one another?

A

True

44
Q

What are some causes for atrial fibrillation?

A
  • Enlargement of the atria (due to valve lesions)
  • Inadequate emptying of the ventricles causing blood to back up into the atria

A. White- Human Physiology (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions