Chapter 9

Question 1

TRUE/FALSE

The chest leads are the only unipolar leads in the standard 12-lead ECG.

Answer 1

false

Question 2

TRUE/FALSE

When you read a 12-lead ECG from left to right, the ECG tracing is continuous.

Answer 2

true

Question 3

TRUE/FALSE

Placement of right chest leads is identical to the standard chest leads except on the right side of the chest.

Answer 3

true

Question 4

TRUE/FALSE

An abnormal (i.e., pathologic) Q wave indicates the presence of dead myocardial tissue.

Answer 4

true

Question 5

Where should the positive electrode for lead V5 be positioned?

Answer 5

Where should the positive electrode for lead V5 be positioned?

Question 6

A standard 12-lead ECG provides views of the heart in _____.

Answer 6

both the frontal and the horizontal planes

Question 7

Poor R-wave progression is a phrase used to describe R waves that decrease in size from V1 to V4. This is often seen in an _____ infarction.

Answer 7

anteroseptal

Question 8

Which leads look at adjoining tissue in the anterior region of the left

Answer 8

V2, V3, V4

Question 9

Lead V1 views the _____.

Answer 9

septum

Question 10

Lead aVL views the _____.

Answer 10

lateral wall of the left ventricle

Question 11

Which of the following leads should be used to view the right ventricle?

Answer 11

V4R

Question 12

Lead V3 views the _____ wall of the left ventricle.

Answer 12

anterior

Question 13

Anterior or lateral wall myocardial infarctions are most often a result of an occlusion of the _____ coronary artery.

Answer 13

left

Question 14

Which leads look at adjoining tissue in the inferior region of the left ventricle?

Answer 14

II, III, aVF

Question 15

Lead V5 views the _____ wall of the left ventricle.

Answer 15

lateral

Question 16

The inferior wall of the left ventricle is supplied by the _____ coronary artery in most of the population.

Answer 16

right

Question 17

Where should the positive electrode for lead V1 be positioned?

Answer 17

Right side of the sternum, fourth intercostal space

Question 18

Lead II views the _____ wall of the left ventricle.

Answer 18

inferior

Question 19

Which leads face the septum?

Answer 19

V1, V2

Question 20

Which of the following ECG changes is one of the earliest to occur during an ST-elevation infarction, but may have resolved by the time the patient seeks medical assistance?

Answer 20

Hyperacute T waves

Question 21

Hypertrophy refers to a(n) _____.

Answer 21

increase in the thickness of a heart chamber because of chronic pressure overload

Question 22

Patients who experience a(n) _____ myocardial infarction have a greater incidence of heart failure and cardiogenic shock than those who have myocardial infarctions affecting other areas of the left ventricle.

Answer 22

anterior

Question 23

An ECG machine’s sensitivity must be calibrated so that a 1-millivolt electrical signal will produce a deflection measuring exactly _____ mm tall.

Answer 23

10

Question 24

Normal electrical axis lies between _____ degrees.

Answer 24

–30 and +90

Question 25

Lead I is perpendicular to lead _____.

Answer 25

aVF

Question 26

Lead I views the _____.

Answer 26

lateral wall of the left ventricle

Question 27

Indicative ECG changes observed in leads V1, V2, V3, and V4 suggest that the _____ wall of the _____ ventricle is affected.

Answer 27

anteroseptal; left