EKG II Lecture Powerpoint

Question 1

Interval definition

Answer 1

Segment plus a wave, a function of time

Question 2

AVR lead will often write ___ complexes (pos or neg)

Answer 2

Neg

Question 3

Y axis of an EKG is measured in ___ but is almost always commonly described in ____

Answer 3

mv, mm

Question 4

Segment definition

Answer 4

Baseline between waves

Question 5

PR interval function and normal interval (in sec and squares)

Answer 5

Measures time required for impulse to travel from SA node to ventricular myocardium, a good estimate of AV node function to slow things down, .12-.2 sec or 3 to 5 squares

Question 6

P wave function and normal interval (in sec and squares and mv vertically)

Answer 6

Just before QRS complex representing atrial depolarization, should be <3 small squares (.12 sec) in duration and <3 squares in amplitude (.3 mv)

Question 7

Tall P wave indicates….

Answer 7

…right atrial enlargement

Question 8

PR segment function and 
 normal interval (in sec and squares)

Answer 8

Follows P wave and should be flat, represents slow conduction thru av node and ends with spike in R wave, should be .12-.2 sec or 3-5 squares

Question 9

Delta wave

Answer 9

A sign of early excitation of ventricles, indicative of re-entry such as global (wolff-parkinson-white syndrome causing tachycardia in children)

Question 10

QRS complex function and normal interval (in sec and squares)

Answer 10

Represents ventricular depolarization, generally less than .12 sec or 3 squares

Question 11

Q wave function and normal interval (in sec and squares)

Answer 11

1st neg deflection after the P wave, should be less than .04 sec or 1/3 amplitude of QRS complex

Question 12

R wave function and normal interval (in mm vertically)

Answer 12

1st positive deflection of QRS complex indicative of ventricular depolarization, amplitude should be between 1-15mm

Question 13

ST segment function

Answer 13

Represents period from end of ventricular depolarization to beginning of repolarization, should be completely horizontal except in cases of infarct or ischemia

Question 14

J point

Answer 14

Junction between S wave and ST segment, normally at a 90 degree angle, used in a stress test as a point of measurement for st segments

Question 15

T wave function and normal interval

Answer 15

Represents ventricular repolarization, longer than depolarization, round and positive

Question 16

QT interval function

Answer 16

Measures QRS to end of T wave, represents ventricular depolarization to end of ventricular repolarization,

Question 17

Corrected QT interval

Answer 17

concern when .45 sec, considered normal when less than half the RR interval

Question 18

U wave

Answer 18

Follows T wave, not always present, same direction of deflection of the T but much smaller amplitude (often not picked up), unknown what it represents

Question 19

Hyperkalemia causes ___. What are 3 other things it sometimes causes?

Answer 19

Increased amplitude and peaking of T wave

• prolonged PR interval
• Prolonged QRS complex
• flattened P wave

Question 20

Hypokalmeia causes ___. What are 2 other things it sometimes causes?

Answer 20

flattened or inverted T wave

• prominent U wave
• slight depression of ST segment

Question 21

Wave definition

Answer 21

A positive or negative tick in response to changing signal (depolarization) that forms characteristics structures of the EKG

Question 22

Inverted P wave indicates…

Answer 22

…retrograde conduction from AV junction

Question 23

1 square represents what values in mm, sec, and mv horizontal and vertically?

Answer 23

1mm or .04 sec horizontally, and 1mm or .1mv vertically

Question 24

Widened QRS complex indicates….

Answer 24

…conduction delay

Question 25

Significant (Q) wave

Answer 25

Occurs when the length is >.04 sec or one square or 1/3 the amplitude of the entire QRS complex

Question 26

R wave gets progressively ___ from V1 to V4-5

Answer 26

Bigger

Question 27

Loss of R wave progression can indicate…

Answer 27

…loss of left ventricular myocardial conduction (MI)

Question 28

RVH causes larger R waves in V __, LVH causes it in V___

Answer 28

1-2, 5-6

Question 29

S wave function

Answer 29

Caused by terminal depolarization of right ventricle in lead I, is large in V1 and larger in V2, then progressively smaller V3-6

Question 30

ST segment elevation indicates…

ST segment depression indicates…

Answer 30

elevation indicates acute infarction and pericardidits, and depression in ischemia

Question 31

T wave abnormalities

Answer 31

, may become inverted, peaked, or flattened due to ischemia, infarction, or medications

Question 32

What lead is the T wave in verted in? What 6 is it upright in? What is it variable in?

Answer 32

Inverted in AVR, upright in I,II, V3-6, variable in AVL, AVF, III, V1, V2

Question 33

Widened QRS complex in the right precordial leads indicates ____, widened in the left indicates ____

Answer 33

right bundle branch block, left bundle branch block

Question 34

R waves should get progressively bigger from ____ to ___, extra large R waves in ___ indicates RVH, extra large R waves in ___ indicates LVH

Answer 34

V1, V5, V1-2, V5-6

Question 35

S waves should get progressively ____ from V1 to V6

Answer 35

smaller