EKG

Question 1

PR interval length in boxes and seconds

Answer 1

3-5 boxes

.12-.20 seconds

Question 2

QRS complex length and times

Answer 2

1. 5-3 boxes

0. 06-0.12 seconds

Question 3

QT interval

Answer 3

Beginning of QRS to end of T

360-440 msec

Question 4

Impulse slow through AV node?

Answer 4

To allow complete atrial emptying

Question 5

Wide QRS: supraventricular origin (3)

Answer 5

1- ventricular pre-excitation
2- pacemaker induced QRS
3- interventricular conduction defect

Question 6

Wide QRS: Ventricular origin (4)

Answer 6

1- ventricular tachycardia
2- 3rd degree AV heart block
3- idioventricular rhythm
4- Premature ventricular complexes

Question 7

Short PR interval: (4)

Answer 7

1. PACS
2. Atrial tachycardia
3. Ventricular pre-excitation
4. Junctional rhythms

Question 8

Long PR Intervals: (1)

Answer 8

1. 1st degree AV block

Question 9

Varying PR intervals: (2)

Answer 9

1. 2nd degree AV block type 1

2. Wandering atrial pacemaker

Question 10

Not measurable or absent PR interval: (3)

Answer 10

1. Atrial fibrillation
2. Ventricular dysrhythmia
3. 3rd degree AV block

Question 11

Tall amplitude QRS complexes: (3)

Answer 11

Hypertrophy
Abnormal pacemaker
Aberrantly conducted beat

Question 12

Abnormally wide QRS: (2)

Answer 12

Aberrantly conducted or originated beats

Question 13

What is a U wave?

Answer 13

• occurs on EKQ following T wave (especially V2 and V4)

- occurs secondary to bradycardia or hypokalemia

Question 14

ST segment is elevated or depressed in:

Answer 14

Myocardial ischemia

Question 15

Normal QT interval length times vs. QTc times:

Answer 15

W: less than or equal to 0.45-0.46 sec
M: less than or equal to 0.44 sec
- time for ventricular depolarization and repolarization
- precise QT interval is calculated correcting for heart rate: QTc
- M: QTc < 420 ms
- W: QTc < 460 ms

Question 16

Normal QT interval should be:

Answer 16

Less than 1/4 of the R-R interval

Question 17

Prolonged QT secondary to and predispose pt. To:

Answer 17

• predispose pt to threatening dysrythmia in the setting of MI or myocardial ischemia
• May be a dose-limiting effect of some anti-arrhythmias

Question 18

Shortened QT interval:

Answer 18

• Found in hypercalcemia or digoxin toxicity

- abnormal is QTc < 350 ms

Question 19

MC cardiac rhythm disturbance

Answer 19

Atrial dysrythmias

Question 20

MC cardiac rhythm disturbance type

Answer 20

Atrial re-entry