18. Normal ECG

Question 1

what direction does a normal vector point for electrical cardiac activity

Answer 1

from upper right to lower left

Question 2

how is the p wave normally represented in aVR

Answer 2

inverted

Question 3

where is the p-wave normally upright

Answer 3

lead 1, 2, V4-V6, aVF

Question 4

how long is a normal PR interval & what does it represent

Answer 4

0.12 - 0.2 secs ==> time from SA node to ventricular M

(anything greater = anomaly)

Question 5

what is the timing for a normal QRS complex

Answer 5

0.05 - 0.1 sec

Question 6

what does a normal Q wave look like

Answer 6

narrow/small

1-2 mm in lead 1, aVL, aVF, V5-6

Question 7

what is indicated by a QRS complex > 0.12 secs long

Answer 7

bundle branch block

Question 8

what does a normal ST segment look like

Answer 8

isoelectric (around baseline)

no more than 1 mm elevated in standard lead & 2 mm in chest lead

no more than 1/2 mm depression

Question 9

what does a ST depression show

Answer 9

subendocardial injury/ischemia

Question 10

what does a ST elevation show

Answer 10

subepicardial or transmural injury/ischemia

Question 11

where is a T wave normally upright

Answer 11

leads 1, 2, V3-V6

Question 12

how is the T wave represented in aVR

Answer 12

inverted

Question 13

what is the shape of a T wave

Answer 13

slightly round, asymmetrical

height = no more than 5 mm in standard lead and 10 mm in precordial leads

Question 14

what can a tall upright or inverted T wave show

Answer 14

ischemic pattern

hyperkalemia (tall upright esp)

Question 15

ST elevation shows patterns of..

Answer 15

injury

Question 16

abnormal Q wave or QS complex shows-

Answer 16

pattern of necrosis or infarcation

Question 17

what is the pattern for counting HR?

Answer 17

every large box count down - 300, 150, 100, 75, 50

Question 18

how do you find the axis on an EKG

Answer 18

1. look at lead 1 and aVF - are they both up? if so = normal
2. find smalled deflection
3. look at lead that is perpendicular to the deflection
4. axis = direction perpendicular lead is pointing

Question 19

how is P-mitrale represented on an ekg

Answer 19

broad, wide, notched

Question 20

what is indicated by a tall pointed P wave

Answer 20

P-pulmonale

Question 21

if a p wave is inverted –>

Answer 21

signs of AV jxnal rhythm

Question 22

prolonged PR intervals can be signs of–

Answer 22

AV block (coronary disease, rheumatic disease, etc)

hyperthyroidism

normal variation

Question 23

a shortened PR interval is indicitave of–

Answer 23

AV jxnal or low atrial rhythm

Wolff-parkinson-white syndrome

lown-ganong-levine syndrome

glycogen storage

htn

normal variant

Question 24

what can this indicated

Answer 24

bundle branch block

Question 25

a large Q wave can be a sign of --

Answer 25

an infarction

Question 26

Answer 26

ST elevation from myocardial injury (acute/infarction) =ST "fireman's hat"

Question 27

a tall T wave can be indicative of...

Answer 27

myocardial ischemia in pt w/ angina but w/o infarction or inferior infarction (tall upright)

Question 28

a deep inverted symetrical T wave can be a result of -

Answer 28

anterior infarction

Question 29

what are signs of a normal sinus rhythm

Answer 29

P wave before each QRS complex PR interval \< 0.2 sec QRS \< 0.12 sec

Question 30

HR \> ______ = tachycardia

Answer 30

\> 100

Question 31

HR less than 60 =

Answer 31

bradycardia

Question 32

is P waves follow QRS, what may be the rhythm

Answer 32

SVT (AV nodal re-entry tachycardia) jxnal rhythm

Question 33

what rhythm may be present if no P waves are present

Answer 33

A-fib, atrial flutter, jxnal/ventricular escape rhythms, jxnal tachycardia, VT

Question 34

what are problems seen with L axis deviation

Answer 34

LV hypertrophy L bundle branch block Heart attack precnancy, ascites, abdominal tumor

Question 35

what are problems seen with R axis deviation

Answer 35

lung disease RV hypertrophy R bundle branch block

Question 36

if an ekg shows lead 1 and aVF to be positive, the axis is-

Answer 36

normal 0-90

Question 37

how are the leads represented in a L axis deviation

Answer 37

lead 1 = + aVF = - (0 to -90)

Question 38

if lead 1 is neg & aVF is pos, then what axis do you have

Answer 38

right axis 90-180