Basics

Question 1

Inferior Leads

Answer 1

II, III, aVF

Question 2

High Lateral Leads

Answer 2

I, aVL

Question 3

Anterior Leads

Answer 3

V3-V4

Question 4

Posterior Leads

Answer 4

None

Question 5

Reciprocal of II, III, aVF

Answer 5

I, aVL

Question 6

Reciprocal of V1-V4

Answer 6

None

Question 7

Reciprocal of I, aVR

Answer 7

II, III, aVF

Question 8

Lead I angle

Answer 8

0

Question 9

Lead II angle

Answer 9

+60 deg

Question 10

Lead III angle

Answer 10

+120 deg

Question 11

Lead aVL angle

Answer 11

-30 deg

Question 12

Lead aVF angle

Answer 12

+90 deg

Question 13

Lead aVR angle

Answer 13

-150 deg

Question 14

Normal qRS complex width

Answer 14

80-90 ms (anything under 100 ms OK, >120 ms considered wide complex)

Question 15

Occluded Vessel MI in Lead II, III, aVF

Answer 15

Posterior Descending Artery (predominately supplied either from Right coronary in ~80% of people or Left circumflex in ~20 % of people)

Question 16

Atrial Diastole portion of EKG

Answer 16

QT interval (from beginning of QRS complex to end of T wave)

Question 17

Ventricular Systole portion of EKG

Answer 17

QT interval (from beginning of QRS complex to end of T wave)

Question 18

Ventricular Diastole portion of EKG

Answer 18

PR interval (from beginning of P to beginning of QRS)

Question 19

AV nodal pause portion of EKG

Answer 19

PR segment (from end of P to beginning of QRS complex)

Question 20

What determines amplitude of EKG waves?

Answer 20

Mass of moving segment+ direction of electrical signal (hence higher in LVH)

Question 21

Normal PR interval

Answer 21

120-200 ms

Question 22

How does myocardial cell membrane generate negative charge (polarized state)

Answer 22

2 potassiums in, 3 sodiums out with Na+-K+-ATPase pump (net -1), as well as rapid acting voltage gated channels allowing massive influx

Question 23

Normal axis

Answer 23

-15 deg to +75 deg

Question 24

Appropriate range of separation for T axis vs QRS axis

Answer 24

Within 70 deg of one another–> indicates coordinated ventricular depolarization and repolarization

Question 25

Apical Lateral Leads

Answer 25

V5-V6

Question 26

Anteroseptal Leads

Answer 26

V1-V2

Question 27

Lead w/ best view of right ventricle in adult?

Answer 27

V1

Question 28

Signs of MI

Answer 28

Any or all of the following: 1. ) Pathological Q Waves (>/= 25% of R wave amplitude) 2. ) ST-T elevation ("current of injury") 3. ) T wave inversion ("ischemia") WITH the following changes in reciprocal leads (any or all of the below): 1. ) Increased height of R wave 2. ) ST-T depression 3. ) Tall, symmetrical T waves

Question 29

EKG Signs of MI

Answer 29

Any or all of the following: 1. ) Pathological Q Waves (>/= 25% of R wave amplitude) 2. ) ST-T elevation ("current of injury") 3. ) T wave inversion ("ischemia") WITH the following changes in reciprocal leads (any or all of the below): 1. ) Increased height of R wave 2. ) ST-T depression 3. ) Tall, symmetrical T waves

Question 30

Early Repolarization EKG appearance

Answer 30

When QRS complex does not drop all the way to isoelectric line, but has "early" T wave, but without reciprocal changes (can be mistaken for STEMI otherwise)

Question 31

Right atrial abnormality EKG appearance

Answer 31

P waves found consistently across limb leads that are not <2.5 mm in amplitude or <100 ms in length--> can be biphasic, or many other appearances, but right atrium specific to limb leads.

Question 32

Left atrial abnormality EKG appearance

Answer 32

P waves found consistently across precordial leads that are not <2.5 mm in amplitude or <100 ms in length--> can be biphasic, or many other appearances, but left atrium specific to precordial leads.

Question 33

Junctional Rhythm EKG appearance

Answer 33

No P Waves--> pacing occurs through AV node rather than SA node

Question 34

Significance of Wide Complex QRS

Answer 34

Ventricular Pacing

Question 35

Damaged chamber MI in Leads II, III, aVF

Answer 35

Right Ventricle

Question 36

Occluded Vessel MI in Leads V1-V4

Answer 36

Left Anterior Descending Artery

Question 37

Damaged chamber MI in Leads V1-V4

Answer 37

Left Ventricle

Question 38

Occluded Vessel MI in Leads V1-V2

Answer 38

Septal branch of Left Anterior Descending Artery

Question 39

Damaged chamber MI in Leads V1-V4

Answer 39

Septum separating RV and LV (septum tissue is predominately LV)

Question 40

Occluded Vessel MI in Leads I, V5-V6

Answer 40

Left Circumflex Artery

Question 41

Damaged Chamber MI in Leads I, V5-V6

Answer 41

Lateral wall of Left Ventricle