ch.1: basic principles

Question 1

1790

Answer 1

Galvani- frog legs dance w/Electrical activity

Question 2

1880

Answer 2

• Ludwig and Waller
• hearts rhythmic electrical stimuli on skin
• electrodes

Question 3

1901

Answer 3

• Einthoven “godfather”
• invented EKG machine

Question 4

T/F: EKG and ECG are different from each other?

Answer 4

False. Same thing different letter

Question 5

What does an EKG do?

Answer 5

• record electrical activity in heart
• heart rate and rhythms
• depolarization and repolarization of <3 muscle

Question 6

What is depolarization?

Answer 6

Contraction

Question 7

What is repolarization?

Answer 7

Fill up, refill, relaxing, expanding

Question 8

What are the 2 phases of the cardiac cycle?

Answer 8

Contraction and Relaxation

Question 9

Myocytes

Answer 9

• Myocardial cells
• negatively charged @ rest

Question 10

What happens to myocytes during depolarization?

Answer 10

They become positive resulting in contraction

Question 11

What comes after a contraction?

Answer 11

Repolarization

Question 12

What are intercalated discs?

Answer 12

allows myocardial cells to communicate and work in unison with each other and transmission of impulse from one to the next

Question 13

What does SA node mean?

Answer 13

Sinus node or sinal atrial node

Question 14

Where is the SA node located?

Answer 14

upper-posterior wall of right atrium

Question 15

What is the dominant pacemaker called?

Answer 15

SA node

Question 16

T/F: The SA node contracts both atria?

Answer 16

True. Right and Left. automatically

Question 17

What does the SA node generate on EKG?

Answer 17

• “P” wave
• tells us atrium contracts

Question 18

Where is the AV node located?

Answer 18

above trio-ventricular valves (floor of right atrium)

Question 19

What does the AV node do?

Answer 19

• Electrical conduction between atria and ventricles
• allows for pause (flat line @ baseline) on EKG
• blood flow from atria to ventricles

Question 20

What does the bundle of HIS do?

Answer 20

carries impulse from AV node to bundle branches

Question 21

What makes up the ventricular conduction system?

Answer 21

• HIS bundle
• L/R bundle branches
• Purkinje fibers

Question 22

What does the bundle of HIS generate on EKG?

Answer 22

produces the QRS complex

Question 23

What is the inherent rate of the SA node?

Answer 23

60-100 bpm

Question 24

What is the inherent rate of the Atria?

Answer 24

60-80 bpm

Question 25

What is the inherent rate of the AV node?

Answer 25

40-60 bpm

Question 26

What is the inherent rate of the ventricles?

Answer 26

20-40 bpm

Question 27

What is the order of the electrical system of the heart?

Answer 27

• SA node
• AV node
• Bundle of HIS
• L/R branches
• Purkinje fibers

Question 28

What is the ST segment?

Answer 28

• beginning phase of ventricular repolarization
• horizontal segment of baseline follows QRS complex

Question 29

What is the T wave?

Answer 29

• rapid phase of ventricular repolarization and is full of blood
• follows QRS complex

Question 30

what is the QT interval?

Answer 30

• beginning of Q wave and end of T wave
• duration of ventricular systole
• less than 1/2 of total R-R interval

Question 31

What does overdrive suppression do?

Answer 31

tells atrial foci, AV node, and ventricles to not contract

Question 32

how long should the QT interval be?

Answer 32

less than 1/2 the total R-R interval

Question 33

what isn’t shown on an EKG?

Answer 33

cant see atrial repolarization on EKG bc its hidden in/during ventricle depolarization

Question 34

What makes up the QRS complex?

Answer 34

the HIS bundle

Question 35

What is the order of inherent heart rate?

Answer 35

• SA node
• atria foci (1st backup)
• AV node (2nd backup)
• ventricles (purkinje, 3rd backup)