Tools: ECG

Question 1

ECG. What do leads I, II and VL ‘look at’?

Answer 1

The left lateral surface of the heart.

Question 2

ECG. What do leads III and VF ‘look at’?

Answer 2

The inferior surface of the heart.

Question 3

ECG. What does lead VR ‘look at’

Answer 3

The right atrium.

Question 4

ECG. What do leads V1 an V2 look at?

Answer 4

The right ventricle

Question 5

ECG. What do leads V3 and V4 look at?

Answer 5

The septum between the ventricles.

Question 6

ECG. What do leads V5 and V6 look at?

Answer 6

Anterior and lateral walls of left ventricle.

Question 7

Which lead do you look at to show rhythm.

Answer 7

The one that shows the P wave most clearly: lead II.

Question 8

Compare VR and lead II

Answer 8

They are opposite; VR is mostly negative, lead II mostly upward.

Question 9

What is indicative of right axis deviation?

Answer 9

Lead I with a negative QRS complex, leads II and III with it positive.

Question 10

What is indicative of left axis deviation?

Answer 10

Positive but small lead I QRS. Negative leads II and III

Question 11

If the RR interval in large squares is 1, what is the HR?

Answer 11

300

Question 12

If the RR interval in large squares is 2, what is the HR?

Answer 12

150

Question 13

If the RR interval in large squares is 3, what is the HR?

Answer 13

100

Question 14

If the RR interval in large squares is 4, what is the HR?

Answer 14

75

Question 15

If the RR interval in large squares is 5, what is the HR?

Answer 15

60

Question 16

If the RR interval in large squares is 6, what is the HR?

Answer 16

50

Question 17

How wide is a normal QRS

Answer 17

about 3 small squares

Question 18

Name the limb leads clockwise from VR

Answer 18

VR, VL, I, II, VF, III

Question 19

What are the chest leads?

Answer 19

V1 - V6

Question 20

What is a normal cause of left axis deviation?

Answer 20

Conduction defect.

Question 21

What is a normal cause of right axis deviation?

Answer 21

Increased muscle bulk on the right side.

Question 22

How to report an ECG

Answer 22

Name and date
Rate and rhythm
Conduction defects
A description of QRS intervals
ST segments and T waves.

Question 23

When is the transition point in an ECG?

Answer 23

When the chest leads shift from being predominantly negative to predominantly positive e.g where R = S. It is normally at V3/V4

Question 24

How does the transition point move in RV enlargement?

Answer 24

It shifts to V4/V5/V6

Question 25

If there is a prolongued PR interval of greater than 5 small squares, what condition does this suggest, and what are the causes?

Answer 25

First degree heart block. Coronary artery disease, acute rheumatic carditis, digoxin toxicity and electrolyte disturbances.

Question 26

What is it called when there is a progressive lengthening of the PR interval?

Answer 26

Mobitz type 1, second degree heart block, usually benign.

Question 27

What is it called if most beats have a constant PR, but there is an extra p wave sometimes?

Answer 27

Mobitz type 2, which may herald third degree heart block.

Question 28

What does an ECG with ST elevation in leads II, III and aVF and also in C5 and C6 suggest?

Answer 28

An inferolateral infarction

Question 29

If there are ischaemic changes in leads I, aVL, and leads V2, V3 and V4, where is the ischaemia?

Answer 29

In the apex.

Question 30

If there are ischaemic changes in leads V2 and V3 only, where is the ischaemia?

Answer 30

Anteroseptal: LAD

Question 31

If there are ischaemic changes in leads I, aVL, and leads V5 and V6, where is the ischaemia?

Answer 31

anterolateral: left circumflex artery

Question 32

If there are ischaemic changes in leads III and aVF, and leads V5 and V6, where is the ischaemia?

Answer 32

Posterolateral

Question 33

If there are ischaemic changes in leads II, III and aVF, where is the ischaemia?

Answer 33

inferior - either right coronary artery or left circumflex (20%)

Question 34

If there are ischaemic changes in leads III and aVF, and possibly V2, where is the ischaemia?

Answer 34

Right ventricle

Question 35

Which are the lateral leads?

Answer 35

I, aVL, V5 and V6

Question 36

Which are the inferior leads?

Answer 36

II, III and aVF

Question 37

Which are the septal leads?

Answer 37

V1 and V2

Question 38

Which are the anterior leads?

Answer 38

V3 and V4

Question 39

Which artery is blocked in an anterior MI?

Answer 39

Left anterior descending.

Question 40

Which artery is blocked in an septal MI?

Answer 40

Left anterior descending

Question 41

Which artery is blocked in a lateral MI?

Answer 41

Left circumflex artery

Question 42

Which artery is blocked in an inferior MI?

Answer 42

Right coronary artery (80%) or left circumflex (20%)

Question 43

Which artery is blocked in an posterior MI?

Answer 43

RCA or LCX

Question 44

Which artery is blocked in an right ventricle MI?

Answer 44

RCA

Question 45

What does an ECG with ST elevation in leads II, III and aVF and also in C5 and C6, and ST depression in I and aVL?

Answer 45

A larger infero-lateral myocardial infarction.

Question 46

What does an ECG with ST elevation and evolving Q waves in leads V1-4 suggest?

Answer 46

Acute anterior myocardial infarction.

Question 47

What is the ECG change in a positive exercise stress test?

Answer 47

ST depression

Question 48

Signs of angina on an ECG.

Answer 48

Usually normal, can show ST depression, flat or inverted T waves, signs of past MI.

Question 49

ECG for Prinzmetal's angina.

Answer 49

ST elevation during pain.

Question 50

Classic ECG for an MI

Answer 50

Hyperacute T waves, ST elevation or new LBBB within hours, then T wave inversion and pathological Q waves over hours to days.

Question 51

Saddle shaped ST segment signifies...

Answer 51

Pericarditis - although can also be normal ECG.

Question 52

Cause of widespread PR depression

Answer 52

Pericarditis - most specific ECG marker