1. & 2. EKG Intro (Lead Placement)

Question 1

blood flow through heart

Answer 1

1. IVC/SVC
2. RA
3. Tricuspid valve
4. RV
5. Pulmonary valve
6. Pulm arteries
7. Lungs
8. Pulm veins
9. LA
10. bicuspid/mitral valve
11. LV
12. aortic valve
13. aorta

Question 2

cell to cell contraction of depolarization is carried by what ions?

Answer 2

Na+

Question 3

depolarization is when?

Answer 3

cells become posiitve

Question 4

what causes heart contraction

Answer 4

depolarization of myocytes (positive cells!)

Question 5

what does p wave represent

Answer 5

depolarization of atria

Question 6

what does QR interval represent

Answer 6

AV node delay allowing ventricles to fill

Question 7

what does QRS complex represent

Answer 7

ventricular depolarization

Question 8

what does ST segment represent

Answer 8

beginning of ventricular repolarization

Question 9

what does t wave represent

Answer 9

ventricular repolarization

Question 10

which node is the dominant pacemaker?

Answer 10

SA node

Question 11

order of pacemaker cells if failure + their bpms

Answer 11

1. SA node (60-100 bpm)
2. AV node (60-80 bpm)
3. Junctional Foci (40-60 bpm)
4. Ventricular Foci (20-40 bpm)

Question 12

how long is the width of one small box? 1 big box?

Answer 12

0.04s ; 0.20s

Question 13

how tall is 1 small box? 1 big box?

Answer 13

1mm; 5mm

Question 14

what does an upward deflection mean?

Answer 14

depolarization is occuring in a direction toward the pos electrode

Question 15

describe limb lead I

Answer 15

• R hand negative
• L hand positive
• goes toward L hand

Question 16

describe limb lead II

Answer 16

• R hand negative
• foot positive
• goes toward foot

Question 17

describe limb lead III

Answer 17

• L hand negative
• foot positive
• goest toward foot

Question 18

describe concept of augmented limb leads

Answer 18

create a new (imaginary) lead between two existing limb leads

Question 19

describe aVR

Answer 19

• “negative” exists between L hand and foot
• positive end at R hand

Question 20

describe aVL

Answer 20

• negative exists between R hand and foot
• positive end at L hand

Question 21

describe aVF

Answer 21

• negative exists between R and L hands
• positive end at foot

Question 22

what are the precordial leads?

Answer 22

chest leads

Question 23

where is positive end of precordial leads

Answer 23

at the electrode that is on the chest

Question 24

describe normal R wave progression

Answer 24

R waves get larger as you move from V1 to V6

Question 25

what lead should you look at for the p wave?

Answer 25

lead II

Question 26

expected size of p wave

Answer 26

* height: less than 2.5mm (2.5 small boxes) * width: less than 0.11s (3 small boxes)

Question 27

define PR interval

Answer 27

start of p wave to the start of the QRS complex (includes P wave + PR interval, NOT QRS complex)

Question 28

expected size of PR interval

Answer 28

less than 1 big box (0.12 to 0.20s)

Question 29

normal size of QRS complex

Answer 29

smaller than 0.12s

Question 30

what is the J point

Answer 30

point between the QRS and the ST segment

Question 31

what two things fully represent ventricular repolarization?

Answer 31

ST segment + T wave

Question 32

what is included in the QT interval

Answer 32

* full QRS complex * ST segment * full T wave

Question 33

what is the u wave?

Answer 33

small pos deflections seen after T wave

Question 34

where are u waves best seen

Answer 34

V2, V3

Question 35

what is inverted u wave specific for? what might u waves be seen with?

Answer 35

* inverted: MI * present: hypokalemia

Question 36

kinds of artifact?

Answer 36

* somatic tremors * baseline sway * artifact masquerading as asystole * toothbrush tachy (masturbating)

Question 37

order for EKG interpretation

Answer 37

1. rate 2. rhythm (reg reg/reg irreg/irreg irreg) 3. p waves 4. PR interval 5. QRS complex 6. axis 7. hypertrophy 8. ST segments 9. T waves