EKG

Question 1

Artery involved in MI when ST elevation in:

II, III, aVF

Answer 1

RCA

inferior MI

Question 2

Artery involved in MI when ST elevation in:

V2 through V4

Answer 2

LAD

Question 3

Artery involved in MI when ST elevation in:

I, aVL, v5, v6

Answer 3

LCX

Question 4

Normal PR interval

Answer 4

0.12 - 0.20 sec (3-5 small boxes)

Question 5

Normal QT interval

Answer 5

Upper limit of QT interval is 0.40 sec at 70 bpm
For every 10 bpm above 70 subtract .02 sec.
Add .02 sec for every 10 bpm below 70

Question 6

Normal QRS complex

Answer 6

0.06 - 0.10 sec (1.5 - 2.5 small boxes)

Question 7

Normal axis

Answer 7

(Positive) I, (Positive) aVF

Question 8

Left axis deviation

Answer 8

(Positive) I, (Negative) aVF

Question 9

Right axis deviation

Answer 9

(Negative) I, (Positive) aVF

Question 10

Right ventricle hypertrophy signs

Answer 10

(1) Right axis deviation, more than 100 deg
(2) in V1 R wave is larger than S
(3) in V6 S wave is larger than R

Question 11

Left ventricle hypertrophy signs

Answer 11

(1) The R wave in V5 or V6 plus the S wave in V1 or V2 exceeds 35 mm.
(2) The R wave in aVL plus the S wave in V3 exceeds 20 in women and 28 in men.

Question 12

Right Bundle Branch Block

Answer 12

(1) RSR’ (i.e. rabbit ears) in V1, V2 (right ventricle)

2) Deep S waves in I, aVL, V5, V6 (left ventricle

Question 13

Left Bundle Branch Block

Answer 13

(1) RSR’ (i.e. rabbit ears) in I, aVL, V5, V6 (left ventricle)
(2) Deep S waves in V1, V2 (right ventricle)

Question 14

Hyperkalemia EKG changes

Answer 14

• Tall peaked T waves (diffuse, NOT localized like in MI)
• PR interval prolongation
• P wave flattens and disappears
• QRS complex widens until it merges with T wave forming a sine wave pattern
• Ventricular Fibrillation

Question 15

Hypokalemia EKG changes

Answer 15

• U wave
• ST segment depression
• flattened T wave
• Prolongation of QRS