10-24-14 Cardiac AP & ECG

Question 0

An upward stroke on an ecg indicates ______

Answer 0

depolarization towards a lead

Question 1

A flat line on an ECG results because of ______

Answer 1

no current flowing to that specific lead

Question 2

A depolarizing current producing a negative reflection is moving in which direction with respect to the specific lead?

Answer 2

Away from the lead = negative reflection

Question 3

A repolarizing current moving towards a lead produces which kind of deflection?

Answer 3

A negative deflection

Question 4

A repolarizing current moving away from a lead =

Answer 4

positive deflection

Question 5

Standard ECG = 1 mv = ____ mm

Answer 5

10 mm, 10 small squares

Question 6

Where is V1 placed?

Answer 6

Anterior chest 4th intercostal space

Question 7

Where is V6 placed?

Answer 7

5th intercostal space lateral chest

Question 8

The magnitude of the signal is directly proportional to _____

Answer 8

the amount of muscle

Question 9

the more muscle present, the more

Answer 9

signal generated

Question 10

What direction does the depolarizing wave move in the ventricle walls?

Answer 10

Subendocardial to epicardial wall

Question 11

Repolarization moves what direction in the ventricular walls?

Answer 11

Epicardium to endocardium

Question 12

What does Concordant refer to in qrs & T waves?

Answer 12

A positive qrs wave usually corresponds to a positive T wave, or a negative qrs wave with a negative T wave

Question 13

Repolarizing is towards or away from a lead?

Answer 13

Away

Question 14

A depolarizing wave is towards or away from a node?

Answer 14

Towards

Question 15

What is this?

Answer 15

The SA & AV node AP

Question 16

What happens at phase 4

Answer 16

1. Spontaneous Depolarization
2. Special/funny Na⁺ channels open

Question 17

What is happening at phase 0

Answer 17

Slow Ca²⁺ channels open

Special K⁺ channels close

Question 18

What is happening at phase 3

Answer 18

Closing of Ca²⁺ gates

Special K⁺ gates open

Question 19

In general, what does an open K⁺ channel mean?

Answer 19

The cell is at, or moving towards, its resting potential

Question 20

What is the drawing depicting?

Answer 20

Atrial and Ventricular depolarization

Question 21

What is happening at phase 4?

Answer 21

• High gK⁺
  
  • AKA K⁺ channels are open and K⁺ is leaving the cell

Question 22

What is happening at phase 0

Answer 22

Na⁺ gates are opening

Question 23

What is happening at phase 1

Answer 23

1. Na⁺ gates close
2. Some K⁺ gates open

Question 24

What is happening at phase 2?

Answer 24

1. Slow Ca²⁺ gates are opening
2. Closing of “special” K⁺ gates

Question 25

What is happening at phase 3?

Answer 25

1. Slow Ca²⁺ gates close
2. “Special” K⁺ gates open
3. Complete repolarization