EKG 1-4

Question 1

a wave of repolarization traveling towards a positive EKG causes a

Answer 1

downward deflection

Question 2

a wave of repolarization traveling away from a positive EKG electrode causes

Answer 2

upward deflection

Question 3

In EKG an interval includes what

Answer 3

at least one of the waves that it is named after

Question 4

PR interval

Answer 4

beginiing of P wave to beginning of QRS

Question 5

QT interval

Answer 5

beginning of QRS to end of T wave

Question 6

ST interval

Answer 6

end of QRS to end of the T wave

Question 7

P wave represents

Answer 7

atrial depolarization

Question 8

T wave represents

Answer 8

ventricular repolarization

Question 9

QRS represents

Answer 9

ventricular depolarization

Question 10

where is early diastole

Answer 10

end of T wave beginning of P wave

Question 11

U wave represents

Answer 11

repolarization of the purkinje fibers

Question 12

each 5 boxes represent

Answer 12

.2 seconds

Question 13

how many big blocks per second

Answer 13

5

Question 14

how many big blocks per minute

Answer 14

300

Question 15

heart rate is equal to 300 divided by

Answer 15

number of big blocks between consecutive beats on standard EKG tracing with regular rhythms

Question 16

for slow heart rates or irregular rhythms the _____-marks may be used to determine heart rate

Answer 16

3 second marks

Question 17

how do you determine the heart rate for slow heart rates or irregular rhythms

Answer 17

count number of cardiac cycles over 2 consectuvei 3 second intervals and multiply by 10

Question 18

lateral leads are

Answer 18

I and AVL

Question 19

inferior leads are

Answer 19

II, III, and AVF

Question 20

normal frontal plane axis is

Answer 20

0-90 degrees

Question 21

O is lead

Answer 21

I

Question 22

positive 30 degrees is

Answer 22

R (-)

Question 23

positive 60 is

Answer 23

lead II

Question 24

positive 90 is LEAD

Answer 24

F

Question 25

positive 120 is

Answer 25

lead III

Question 26

what are the 3 steps for locating QRS in the frontal plane

Answer 26

locate the most isoeletric lead, locate the lead 90 degrees from the most isoeletric lead and the QRS axis is along this lead in the direction corresponding to the polarity of the QRS complex in THAT lead

Question 27

if lead 1 qrs is positive and AVF is negative them

Answer 27

extreme RAD

Question 28

if lead 1 is positive and AVF is positive them

Answer 28

normal

Question 29

if lead 1 is positive and AVF QRS is negative them

Answer 29

LAD

Question 30

V1 is mostly

Answer 30

negative

Question 31

V6 is mostly

Answer 31

positive

Question 32

rules for determining the QRS axis in the horizontal plane

Answer 32

if R to S ration changes from negative to positive after V4- leftward at or before V2- rightward between V2 and V4 then normal if starts negative and stays negative -leftward if starts positive and stays positive--rightward if starts positive and becomes negative by V6 then leffward

Question 33

what is automaticity

Answer 33

ability of specialized cells to spontaneously generate electrical impulses which may then spread throughout surrounding tissue

Question 34

rate for atrial foci

Answer 34

60-80

Question 35

rate of junctional foci

Answer 35

40-60

Question 36

rate of ventricular foci

Answer 36

20-40

Question 37

overdrive suppresion

Answer 37

the pacemaker with the fastest rate is the dominant pacemaker

Question 38

what is escape

Answer 38

a protective mechanism whereby an automaticity focus with the next highest inherent rate begins pacing in the event of a pause or cessation of pacing activity of the previous dominant pacemaker

Question 39

escape beat

Answer 39

transient escape of automaticity focus to generate one beat; occurs when there is a pause in pacing activity in the previously dominant pacemaker

Question 40

escape rhythm

Answer 40

escape of automaticity focus with subsequent pacing by the automaticity focus at its inherent rate which occurs when there is a cessation of pacing activity in the previously dominant pacemaker

Question 41

what is the criteria for sinus rhythm

Answer 41

each QRS complex is preceded by a P wave and the P waves MUST BE positive in lead II and negative in lead AVR

Question 42

normal sinus rhythm is a heart rate of

Answer 42

60-100

Question 43

sinus bradycardia

Answer 43

less than 60 beats/minute

Question 44

sinus tachycardia

Answer 44

sinus rhythm with a heart rate greater than 100 beats/minute

Question 45

what are the criteria for sinus arrhthmia

Answer 45

sinus rhythm criteria and there is a GREATER than .16 (r small boxes) between the shortest and the longest PP intervals within the same EKG tracing

Question 46

what is the most common cause of sinus arrhthmia

Answer 46

respiration

Question 47

inverted P wave in lead two

Answer 47

atrial automaticity focus

Question 48

the key to determining the origin of a completely inverted P wave in lead II is the

Answer 48

length of the PR invertival assuming there is NO AV node dysfunction

Question 49

if automaticity is midwave between AV node and bundle of his then

Answer 49

P wave is nonexistent

Question 50

if P wave is close to the bundle of his them

Answer 50

P wave after QRS