Intro Stuff

Question 1

What is ECG paper?

Answer 1

Graph paper made up of small boxes and larger boxes

Question 2

What does a small box on ECG paper represent?

Answer 2

0.04 sec

Question 3

What does a large box on ECG paper represent?

Answer 3

0.2 sec

Question 4

What do the black tick marks at the top of ECG paper represent?

Answer 4

3 sec intervals

Question 5

What does any deflection from the baseline in an ECG represent?

Answer 5

Electrical activity in the heart

Question 6

What does the P wave represent?

Answer 6

Atrial depolarization

Question 7

What stimulates the P wave?

Answer 7

SA node in the right atrium

Question 8

What are the characteristics of a normal P wave?

Answer 8

Positive, Present, and Preceding a QRS complex (PPP)

Question 9

What does the PR interval represent?

Answer 9

Time for the impulse to travel through the atria and to the ventricles

Question 10

How is the PR interval measured?

Answer 10

From the beginning of the P wave to the beginning of the QRS complex

Question 11

What is the normal range for the PR interval?

Answer 11

0.12-0.20 sec

Question 12

What does the QRS complex represent?

Answer 12

Depolarization of the ventricles

Question 13

How is the QRS complex measured?

Answer 13

From where the QRS complex leaves the baseline until it returns to baseline

Question 14

What is the normal duration for a QRS complex?

Answer 14

Less than or equal to 0.11 sec

Question 15

What does the T wave represent?

Answer 15

Repolarization of the ventricles

Question 16

What is a normal characteristic of the T wave?

Answer 16

Positive deflection

Question 17

What does the QT interval represent?

Answer 17

Time for the ventricles to depolarize and repolarize

Question 18

How is the QT interval measured?

Answer 18

From the beginning of the QRS complex to the end of the T wave

Question 19

What is considered a prolonged QT interval in men? in women?

Answer 19

0.47 sec or longer in men and 0.48 sec or longer in women

Question 20

What is considered a prolonged QT interval in this course?

Answer 20

0.50 sec or longer

Question 21

What medications can prolong the QT interval? (Name one category)

Answer 21

Antidysrhythmics
Antidepressants
antipsychotics
Antibiotics
+Others (ondansetron)

Question 22

What does the ST segment represent?

Answer 22

Early part of ventricular repolarization

Question 23

What does an abnormal ST segment indicate?

Answer 23

Cardiac ischemia

Question 24

What is the J-point in ECG interpretation?

Answer 24

Point where the QRS changes direction into the baseline or T wave

Question 25

What does the U wave represent?

Answer 25

Late repolarization of the purkinje fibres

Question 26

What does the P-P interval represent?

Answer 26

A full cardiac cycle using atrial depolarization as a reference

Question 27

How is the P-P interval measured?

Answer 27

From the beginning of one P wave to the beginning of the next P wave

Question 28

What does the R-R interval represent?

Answer 28

A full cardiac cycle using ventricular depolarization as a reference

Question 29

How is the R-R interval measured?

Answer 29

From the tip of one QRS complex to the tip of the next QRS complex

Question 30

What does artifact in an ECG represent?

Answer 30

Movement or respiratory interference with the ECG monitoring system

Question 31

What should be noted about the T wave in the interpretation?

Answer 31

If the T wave is positive, inverted (below the baseline), biphasic (both above and below the baseline - shown), or peaked (more than half the height of the QRS complex)

Question 32

If there is only one visible wave between QRS complexes, which wave form is it most likely and why?

Answer 32

Because the ventricular muscle mass is larger than that of the atria, in some arrhythmias, the P wave will be buried within the T wave rather than the other way around. In other words, if there is only one visible wave between the QRS complexes, it is more likely to be a T wave than a P wave.

Question 33

Why is a prolonged QT interval concerning?

Answer 33

The increased risk of R-on-T phenomenon in which the next QRS falls on the T wave, too close to the absolute refractory period and initiates a ventricular arrhythmia

Question 34

What is the QRS complex?

Answer 34

It represents ventricular depolarization and is a combination of Q wave, R wave, and S wave If it is entirely positive wave form, labelled R wave if the complex is entirely negative wave form is called a QS wave

Question 35

What is a peaked T wave?

Answer 35

A t wave that has a height on ecg that is half (or more) of the height of the QRS