Lab 8- Cardiac Anatomy

Question 1

What is the function of intercalated discs?

Answer 1

Type of gap junction

Question 2

Heart wall

Answer 2

1. Epicardium (visceral pericardium)
2. Myocardium (muscle)
3. Endocardium (facing ventricles)

Question 3

Describe the position of the valves when the ventricles re relaxed and when they are contracted.

Answer 3

Relaxed- AV valved open, semilunar are closed

Contracted- Semilunar open, AV are closed

Question 4

Systole

Answer 4

Contraction

-atrial systole happens first

Question 5

Diastole

Answer 5

relaxation

Question 6

Cardiac cycle

Answer 6

P wave to P wave

-when the heart goes through full systole and diastole

Question 7

S1 (lubb)

Answer 7

AV valves closing

Question 8

S2 (dubb)

Answer 8

Semi lunar valves closing

Question 9

How much time does one little box represent?

Answer 9

0.04s

Question 10

Hw much time does one large box (5 little) represent?

Answer 10

0.20s

Question 11

How many little boxes equal 1 second?

Answer 11

25 little boxes

Question 12

What voltage is represented by one little box?

Answer 12

.10mV/small box

Question 13

How many little boxes equal 1mV?

Answer 13

10

Question 14

What do P waves represent?
Normal duration?
normal amplitude?
Cause of abnormalities?

Answer 14

atrial depolarization

• <0.12s
• 0.05 to 0.25mV
• mitral valve stenosis or pulmonary hypertension

Question 15

What does the PQ segment represent?

Answer 15

between end of P start of Q

Question 16

What does PR segment represent?

normal duration?

Answer 16

include a wave, atrial systole and depolarization.

- 0.12 to 0.20s

Question 17

What does QRS segment represent?

normal duration?

Answer 17

ventricle depolarization

- 0.06 to 0.12s

Question 18

What does the ST segment represent?

Answer 18

between waves, end of S and start of T, when ventricles are fully contracted.

Question 19

What do T waves represent?

Answer 19

ventricle repolorization

Question 20

What does the ST interval represent?

Answer 20

ventricle contraction and repolarization.

Question 21

What does the Q-T interval represent?

Answer 21

ventricle systole and diastole

Question 22

Normal sinus rhythm (NSR)

Answer 22

75 bpm

Question 23

Sinus Tachycardia

Answer 23

> 100 bpm

Question 24

Sinus Bradycardia

Answer 24

<60 bpm

Question 25

Artifact occurs when something causes sorption in monitoring. Some common causes are:

Answer 25

- movement - muscle tremors - respiratory movements - loose electrode - broken lead wire

Question 26

What causes atrial fibrillation?

Answer 26

something wrong with SA node

Question 27

What causes PVC's?

Answer 27

extra abnormal heart beats that begin in ventricles.

Question 28

What causes 3rd degree or complete heart block?

Answer 28

Only P waves are working, conductive pathway to ventricles not working.

Question 29

What is the relationship between the P wave and QRS?

Answer 29

not synchronized

Question 30

How is 3rd degree block determined on EKG?

Answer 30

A PR interval greater than 20ms

Question 31

What causes ventricular tachycardia?

Answer 31

stress, drugs, heart disease.

Question 32

What causes ventricular fibrillation?

Answer 32

CAD (coronary artery disease), high potassium, fibrosis.

Question 33

What does ST segment elevation indicate?

Answer 33

myocardial infarction

Question 34

What does an inverted T wave indicate?

Answer 34

coronary ascemia, left ventricle hypertrophy

Question 35

What do Q waves indicate?

Answer 35

depolarization of intraventricular septum