Brainscape's Knowledge GenomeTM

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


See full index

physio exam 3 > electrical activity of the heart > Flashcards

electrical activity of the heart Flashcards

1
Q

what are cardiac conduction pathways

A

detailed pathways that aid in fast /coordinated depolarization of the heart

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

why are conduction pathways important

A

allow for different parts of the heart to contract at different times

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

how does conduction travel through the heart

A

SA node&raquo_space; bachman bundle in left atrium» AV node&raquo_space; interventicular septum ( bundle of his)» right and left bundle branches» purkinjee fibers

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

why do the venticles have more conduction pathways

A

have the greatest amount of muscle

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

how does conduction velocty compare in different parts of the heart

A

it is different in deiiferent parts of the heart

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

what is the function of the AV node in terms of conduction velocity

A
  • the AV nodes slows contraction in which it allows for the ventricles to fill before the contract again
  • in other words has a very slow conduction velocity comapred to other parts of the heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how to the AV nodes slow contraction

A
  • they have fewer gap junctions which increases resistance and thus slows conduction velocity
  • AV has less tissue around it so there are less pathways in which impulses can travel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the sequence of cardiac muscle depol

A

1) Atrial depol
> internodal pathways
> bachmans bundle
2) septal depol
> bundle of his
3) anteroseptal depol
> Bundle of his
> intial activation of
purkinjee fibers
4) depol bulk of ventricular myocardium from endocardium to pericardium
5) depol of posterior portion of bsae of left ventricle
6) ventricles are depolarized

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

EKG
- what are the 3 waves and what occurs in each

A
  • first wave: P wave- atrial depol
  • second wave: QRS wave- ventriculare depol and atrial repol
  • thrid wave: T wave- ventriculr repol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what do ECGs represent

A

multiple action potentials in heart within a period of time

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

how does the time in which the atria contract compare to when the ventricles contract

A
  • the ventricals contract once the atria have completely repolarized
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what type of inforamation do ECGs tell us in a medical POV

A
  • HR and rythm
  • conduction velocity
  • condition of the heart tissue
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the difference between a wave and a segemnt on a ECG

A
  • a wave us an upwaward or downward defelction from the isoelectric line
  • a segement is a section on the isolectric like only (no wave included)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does the PR segment and and ST segment represent

A
  • PR segment - goes from the end of the P wave from the beging of the QRS compex
  • ST - from the end of the QRS compex to the beginning of the T wave
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what do elevated segemnts represent

A

there is a distabance in electrical conduction

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

what are intervals in an ECG

A

represent waves and segemtns

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

what is the PR interval and what does it represent

A
  • goes from the beinig of the P wave to the beginning of the QRS complex and represent the time it takes or APs to travel from the SA to the AV node
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the QRS interval and what does it represent

A
  • goes from the begining to the end of the QRS comple and represents the time it takes for ventricular depolarization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the QT interval and what does it represent

A

goes from the beiginning of the QRS complex to the end of the T wave and repesents the time btwn the intitiation of the QRS complex and the end of the t wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is a 12 lead ECG recording

A
  • when 10 leads are placed on the body ( limbs and chest)
  • 12 electrical vectors are recorded
    > 9 direct measuremnts
    > 3 augmented measurements
21
Q

what are the 2 kinds of limb leads

A

bipolar leads and augmneted uniopolar leads

22
Q

where are the bipolar leads placed

A

Lead NE PE

lead I: right arm and left arm
lead 2: right arm and left leg
lead 3: left arm and left leg
NONE GO ON THE RIGHT LEG

23
Q

where are the augmented unipolar leads placed

A

aVR: right arm
aVL: left arm
aVF: left leg

24
Q

what are the ECG precordial chest leads? are they positve or negative electrode

A

V1-V6 postive elctrode

25
Q

MAKE A CARD FOR SLIDE 38

A
26
Q

make a card for slide 39

A
27
Q

KNOW how to calculate hR slide 40

A
28
Q

what is an arthymia

A

an abnormality in the origin and or the conduction of the cardiac impulse

29
Q

normotopic arrhythmias

A

when the electrical impulse originates at the SA node but is eitier too fast too slow or irrgular

30
Q

ectopic arrhythmias

A

orginate from an area other than the SA node

31
Q

Re-entrant arrhythmias

A

when the electrical impulse moves in a continous pattern determined by changes in anatomical arrangement

32
Q

conduction blocks

A

when electrical activity origniates at the SA node and follows the usual conduction pathways but has enexpected blocks or delays

33
Q

pre excitation syndromes

A

when electrical activity moved through an accesory pathway that by passes the normal ones providing an electrical short cut

34
Q

what are the 3 types of normotopic arrhythmias

A
  • Sinus bradycardia
  • Sinus tachycardia
  • Sinus arrhythmia
35
Q

what type of sinus rythm is this

A

normal sinus rythm

36
Q

what type of sinus rythm is and what is it charecterized by

A

bradycardia - an abnormally low sinus rate

37
Q

what type of sinus rythm is this and what is it characterized by

A

sinus tachycardia- an abnormally high sinus rate

38
Q

what tyoe of sinus rythm is this and what is it charecterized by

A

Sinus arrhythmia- an irregular sinus rate

39
Q

what is a first degree heart block and what is the result

A

all action potential are conducted through the AV junction but the speed of conduction is slower resulting in a longer PR interval

40
Q

what is a second degree heart block and what is the result

A

not all action potentials are conducted through the AV junction and thus only some action potential reach the ventricles and some dont.
- this results in some P waves being followed by a QRS comlex but some do not

41
Q

what is a third degree heart block and what is the result?
- what happens at the atria
- what is the result on a ECG

A
  • action potentials are completely blocked at the AV junction and the latent ventricular pacemaker fires to maintain ventricular function
  • the atria are activated by the SA node and ventricles are activated by purkinjee fibers at a slow rate ressulting in know connection btwn the P wave and QRS complex
42
Q

what is fibrillation

A

instead of excitiation starting at the SA node it is the chaotic activation of the muscle with multiple foci being activted at once

43
Q

can you live with fibrilation?
what happens during stress

A

yes because filling of the ventricles is 80% passive ?
- during stress atria cant contribute to the last 20% of blood to maintain metabolic need and canleed to pulmonary hypertenstion

44
Q

what does an ECG of atrial fibrilation look like?

A

no recognizable P waves

45
Q

what is ventricular fibrillation
- what does it look like on an ECG
- is it compatoble with life

A
  • chaotic activation of the ventricular muscle
  • no QRS complex
  • cot compatible with life
46
Q

what are you doin when you shock someone with an AED

A

when you apply a strong voltage to tissue you try to synchronize the heart by fully depolarizing all the cells in the heart ao the SA node can start again and resume normal rythm

47
Q

what is myocardial infarcation

A

can occur when there is a reduction in blood flow (ischemia) to the cardiac muscle which causes damage

48
Q

what are the carrying levels of myocadial infarcation

A
49
Q

aa

A

physio exam 3 (6 decks)

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