Cardiac_ ECGs, anatomy and physio, conditions

Question 1

Right coronary artery

Answer 1

supplies blood to the right atrium and ventricle and part of the left ventricle

Question 2

Left anterior descending artery

Answer 2

supplies blood to the anterior wall of the left ventricle, interventricular septum, right bundle branch, and left anterior fasciculus of the left bundle branch

Question 3

Circumflex artery

Answer 3

supplies blood to the lateral walls of the left ventricle, left atrium, and left posterior fasciculus of the left bundle branch

Question 4

Cardiac veins

Answer 4

collect blood from the capillaries of the myocardium

Question 5

Coronary sinus

Answer 5

returns blood to the right atrium

Question 6

Atrial kick

Answer 6

atrial contraction<br></br>contributes about 30% of the cardiac output

Question 7

Cardiac output

Answer 7

the amount of blood the heart pumps in one minute<br></br>calculation: heart rate x stroke volume

Question 8

Stroke volume

Answer 8

the amount of blood ejected with each ventricular contraction

Question 9

Preload

Answer 9

the passive stretching exerted by blood on the ventricular muscle at the end of diastole

Question 10

Afterload

Answer 10

the amount of pressure the left ventricle must work against to pump blood into the aorta

Question 11

Contractility

Answer 11

the ability of the heart muscle cells to contract after depolarization

Question 12

Sympathetic nervous system

Answer 12

increases heart rate, automaticity, AV conduction, and contractility<br></br>norepinephrine and epinephrine released

Question 13

Parasympathetic nervous system

Answer 13

vagus nerve stimulation reduces heart rate and AV conduction<br></br>acetylcholine released

Question 14

Automaticity

Answer 14

the cell’s ability to spontaneously initiate an impulse (pacemaker cells)

Question 15

Excitability

Answer 15

how well a cell responds to an electrical stimulus

Question 16

Conductivity

Answer 16

the ability of a cell to transmit an electrical impulse to another cardiac cell

Question 17

Contractiltiy

Answer 17

how well the cell contracts after receiving a stimulus

Question 18

Phase 0: rapid depolarization

Answer 18

cells receive an impulse from a nearby cell and is depolarized

Question 19

Phase 1: Early Repolzarization

Answer 19

early rapid repolarization occurs

Question 21

Phase 2: Plateau Phase

Answer 21

A period of slow repolarization occurs

Question 22

Phase 3: Rapid Repolarization

Answer 22

The cell returns to its original state

Question 23

Phase 4: Resting Phase

Answer 23

The cell rests and readies itself for another stimulus

Question 24

SA Node firing rate

Answer 24

60-100 bpm

Question 25

AV Junction firing rate

Answer 25

40-60 bpm

Question 26

Purkinje Fibers firing rate

Answer 26

20-40 bpm

Question 27

Retrograde Conduction

Answer 27

Impulses that are transmitted backward toward the atria

Question 28

Monitor problem: artifact

Answer 28

May appear with excessive movement (wavy, bumpy, tremulous

Question 29

Monitor problem: interference

Answer 29

Caused by electrical power leakage or from other equipment (thick, unreadable)

Question 30

Monitor problem: wandering baseline

Answer 30

All waveforms may be present; can be caused by movement of the chest wall when breathing, poor electrode placement, or poor electrode contact

Question 31

ST segment depression may indicate:

Answer 31

Myocardial ischemia or digoxin toxicity

Question 32

ST segment elevation may indicate:

Answer 32

Myocardial injury

Question 33

Tall, peaked, or tented T waves may indicate:

Answer 33

Myocardial injury or hyperkalemia

Question 34

Prolonged QT interval increases the risk of...

Answer 34

Torsades de pointes

Question 35

Short QT intervals may indicate:

Answer 35

Digoxin toxicity or hypercalcemia

Question 36

Prominent U wave may indicate:

Answer 36

Hypercalcemia, hypokalemia, or digoxin toxicity

Question 37

Characteristics of normal sinus rhythm

Answer 37

Normal rate Regular rhythm Uniform P wave before every uniform QRS complex Normal PR and QT intervals Normal T waves

Question 38

Characteristics of sinus bradycardia