Action potential pathways through the heart and basic EKG readings

Question 1

SA node conduction speed

Answer 1

.05 m/s

Question 2

Bachman’s Bundle conduction speed

Answer 2

1m/s

Question 3

Internodal Fibers conduction speed

Answer 3

1m/s

Question 4

AV node conduction speed

Answer 4

.05 m/s

Question 5

bundle of his conduction speed

Answer 5

2 m/s

Question 6

left and right Bundle Branches conduction speed

Answer 6

2 m/s

Question 7

Purkinji fibers conduction speed

Answer 7

4 m/s

Question 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?

Answer 8

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

Question 9

p wave

Answer 9

depolarization of the atria

Question 10

qrs complex

Answer 10

depolarization of the ventricles

Question 11

t wave

Answer 11

repolarization of the ventricles

Question 12

periods of isoelectricity

Answer 12

no net change in electrical activity

Question 13

pacemaker areas of the heart

Answer 13

SA node
AV node
Perkinji Fibers
work cardiomyocytes?

Question 14

SA node bpm

Answer 14

60-100 bpm

Question 15

AV node bpm

Answer 15

40-60 bpm

Question 16

Purkinji Fibers bpm

Answer 16

20-40 bpm

Question 17

work cardiomyocytes bpm

Answer 17

10-20 bpm

Question 18

1st degree heart block

Answer 18

delay between SA and AV nodes

-not abnormal in young healthy people or a good parasympathetic tone

Question 19

2nd degree heart block

Answer 19

some beats are dropped at the AV nod

-you should put a pacemaker in

Question 20

3rd degree heart block

Answer 20

ventricles receive no impulses

-lead to death

Question 21

p Wave

Answer 21

atrial depolarization

Question 22

P-R interval

Answer 22

AV Conduction time with atria and ventricular contraction

Question 23

QRS complex

Answer 23

ventricular depolarization

Question 24

ST segment

Answer 24

isoelectric line or period of ventricular contraction

Question 25

T wave

Answer 25

ventricular repolarization

Question 26

U wave

Answer 26

repolarization of purkinje fibers?

Question 27

pr segment

Answer 27

isoelectric line of atrial contraction

Question 28

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

Answer 28

it indicates that repolarization is taking toooooo long

-could be caused by hyperkalemia (too much k+ in the ECF)