ECG 1

Question 1

What will a wave of depolarisation approaching the positive electrode cause?

Answer 1

An upward blip

Question 2

What will a wave of depolarisation approaching the negative electrode cause?

Answer 2

A downward blip

Question 3

What is transmitted better - fast or slow events?

Answer 3

Fast events

Question 4

STUDY THE DIAGRAM

Answer 4

Question 5

What causes the P wave?

Answer 5

Wave of depolarisation towards the left leg

Question 6

What is the PR interval?

Answer 6

The time between atrial depolarisation and ventricular depolarisation

Question 7

What is shown by the QRS complex?

Answer 7

Time for whole ventricle to depolarise

Question 8

What is shown by the QT interval?

Answer 8

The length of time the ventricles stay in the plateau phase before they are repolarised

Question 9

What is the Q of the the QRS complex?

Answer 9

The intraventricular septum depolarising left to right

Question 10

What is the R of the QRS complex?

Answer 10

The bulk of the ventricle depolarising from endocardium to epicardium

Question 11

What is the S of the QRS complex?

Answer 11

The upper part of the interventricular septum depolarising

Question 12

Which numbers on the diagram correspond to the Q, R and S of the QRS complex?

Answer 12

1 - Q

2 - R

3 - S

Question 13

Why is the T wave positive?

Answer 13

The wave of repolarisation travels back up the heart

Question 14

Why does the wave of depolarisation that causes the T wave travel back up the heart?

Answer 14

Epicardium is repolarised a lot faster than endocardium

Question 15

When can the axis of the heart be altered?

Answer 15

• Heart rotation
• Hypertrophy of the heart wall

Question 16

What will a changed heart axis result in?

Answer 16

Different readings on the standard limb leads

Question 17

What are the 3 augmented limb leads?

Answer 17

• aVR
• aVL
• aVF

Question 18

What is the orientation of aVR?

Answer 18

• Right arm positive relative to left arm and left leg

Question 19

What is the orientation of aVL?

Answer 19

Left arm is positive compared to right arm and right leg

Question 20

What is the orientation of aVF?

Answer 20

Right foot is positive but it is in the shape of a crucifix

Question 21

STUDY THE AUGMENTED LIMB LEAD ECG TRACE

Answer 21

Question 22

How are the precordial leads arranged?

Answer 22

In front of the heart

Question 23

What anatomical plane is the heart analysed in by the precordial leads?

Answer 23

Transverse plane

Question 24

Since the precordial leads are arranged from V1 (on the right side of the chest) to V6 (on the left side in the mid axillary line) what will the change in signal be?

Answer 24

V1 = negative

V6 = positive

Gradual change through V2 - V5 from negative to positive

Question 25

What is the gradual change in signal type shown by the precordial leads called?

Answer 25

Progression

Question 26

STUDY THE PRECORDIAL LEADS ECG TRACE

Answer 26

Question 27

What is shown by the rhythm strip?

Answer 27

• Heart rate
• Allows you to measure the R-R wave interval
• Tells you if the QRS is preceded by a P wave

HIT ME WITH YA RHYTHM STRIP

Question 28

What will the rhythm strip tell you about the PR interval?

Answer 28

If it is the correct length of time

Question 29

What will the rhythm strip tell you about the QRS complex?

Answer 29

If it is too wide

Question 30

What will the rhythm strip tell you about the QT interval

Answer 30

If it is too long

Question 31

What does STEMI stand for?

Answer 31

ST Elevated Myocardial Infarction

Question 32

What does the extend of STEMI indicate?

Answer 32

The severity of a heart attack

Question 33

What is more serious - a MI with STEMI or a MI without STEMI?

Answer 33

MI with STEMI