Action potential pathways through the heart and basic EKG readings Flashcards Preview

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Flashcards in Action potential pathways through the heart and basic EKG readings Deck (28):
1

SA node conduction speed

.05 m/s

2

Bachman's Bundle conduction speed

1m/s

3

Internodal Fibers conduction speed

1m/s

4

AV node conduction speed

.05 m/s

5

bundle of his conduction speed

2 m/s

6

left and right Bundle Branches conduction speed

2 m/s

7

Purkinji fibers conduction speed

4 m/s

8

why is it essential for the conduction speed to start out very slow at the AV node then speed up in the continuous areas?

holding onto the action potential by essentially being slow to conduct it allows the atria to fully depolarize and contract before the ventricles

9

p wave

depolarization of the atria

10

qrs complex

depolarization of the ventricles

11

t wave

repolarization of the ventricles

12

periods of isoelectricity

no net change in electrical activity

13

pacemaker areas of the heart

SA node
AV node
Perkinji Fibers
work cardiomyocytes?

14

SA node bpm

60-100 bpm

15

AV node bpm

40-60 bpm

16

Purkinji Fibers bpm

20-40 bpm

17

work cardiomyocytes bpm

10-20 bpm

18

1st degree heart block

delay between SA and AV nodes
-not abnormal in young healthy people or a good parasympathetic tone

19

2nd degree heart block

some beats are dropped at the AV nod
-you should put a pacemaker in

20

3rd degree heart block

ventricles receive no impulses
-lead to death

21

p Wave

atrial depolarization

22

P-R interval

AV Conduction time with atria and ventricular contraction

23

QRS complex

ventricular depolarization

24

ST segment

isoelectric line or period of ventricular contraction

25

T wave

ventricular repolarization

26

U wave

repolarization of purkinje fibers?

27

pr segment

isoelectric line of atrial contraction

28

what does it indicate if ventricular repolarization (t wave ) is too long or extended out?

it indicates that repolarization is taking toooooo long
-could be caused by hyperkalemia (too much k+ in the ECF)