ECG Made Easy

Question 1

What do the letters ECG stand for?

Answer 1

ElectroCardioGram

Question 2

What is the heart?

Answer 2

The heart is a pump driven by intrinsic electrical impulses which make the heart beat.

Question 3

What does an ElectroCardioGram do?

Answer 3

An electrocardiogram is a paper recording of that electrical activity.

Question 4

What does the ECG record?

Answer 4

The ECG records where electrical impulses start and how they flow through the heart.

Question 5

What doesn’t the ECG measure?

Answer 5

The ECG does not measure how well the heart is pumping

Question 6

Where does the electrical activity of the heart start?

Answer 6

It starts in the sinoatrial node

Question 7

What is another name for the sinoatrial node?

Answer 7

The sinoatrial node is also called the internal pacemaker

Question 8

Where is the sinoatrial node located?

Answer 8

It is located in the right atrium

Question 9

What is the normal rhythm of the heart called?

Answer 9

It is called the sinus rhythm

Question 10

What is the proper name for the normal rhythm of the heart?

Answer 10

It is called the sinoatrial rhythm

Question 11

What is the way that electrical impulses flow through the heart called?

Answer 11

Conduction

Question 12

What do abnormalities is the electrical activity of the heart result in?

Answer 12

They result in abnormal conduction or rhythms

Question 13

What happens when the heart has abnormal conduction or rhythm?

Answer 13

It causes the heart to go too quickly, too slowly or beat irregularly

Question 14

What can changes to the normal flow of electricity through the heart indicate on an ECG?

Answer 14

They can indicate damaged heart muscle

Question 15

What are the causes of damaged heart muscle?

Answer 15

Infarction, hypertension and pulmonary embolism

Question 16

When should an ECG be recorded?

Answer 16

An ECG should be recorded whenever a patient has
- chest pain
- palpitations
- breathlessness
- dizziness
- an episode of syncope
- an unexplained fall

Question 17

When is it good to have an ECG for a patient who doesn’t fit the regular symptoms?

Answer 17

When the patient has had a stroke or a transient ischemic attack (TIA) as these may be caused by an irregular heart rhythm

Question 18

What is a good practice to consider when deciding whether or not to administer an ECG to a patient?

Answer 18

A patient’s symptoms and physical signs will guide interpretation of the ECG

Question 19

How is an ECG recorded?

Answer 19

Electrodes are placed on a patients limbs and chest to record different views of the heart’s electrical activity.

Question 20

What is each view of the heart called?

Answer 20

It is called a lead

Question 21

How many electrodes are required to get one view(lead) of the heart?

Answer 21

Two electrodes are required to get one view

Question 22

How many views(leads) are required to determine the rhythm of the heart?

Answer 22

One view(one lead) is required to get a rhythm of the heart

Question 23

How many electrodes are attached to each limb?

Answer 23

One electrode is attached to each limb

Question 24

How many views of the heart do four electrodes attached to each limb provide?

Answer 24

Four electrodes attached to each limb provide six limb leads or six different views of the heart

Question 25

What are the six limb leads called?

Answer 25

I, II, III, VL, VF and VR.

Question 26

What did VL, VF and VR used to be called?

Answer 26

AVL, AVF, and AVR, the A is redundant.

Question 27

How many electrodes are placed on the chest?

Answer 27

Six electrodes are placed on the chest

Question 28

What are the six leads that are placed on the heart called?

Answer 28

V1, V2, V3, V4, V5, V6

Question 29

What view of the heart do the six limb leads give us?

Answer 29

They give us six different views of the heart in a vertical plane

Question 30

What view of the heart do the six electrodes give us?

Answer 30

They give us a view of the heart from the front in a horizontal plane

Question 31

What is the proper placement of electrodes on the limbs?

Answer 31

RA (Right arm): Between the right shoulder and right elbow RL (Right leg): Below the right torso and above the right ankle LA (Left arm): Between the left shoulder and the left elbow LL (Left leg): Below the left torso and above the left ankle

Question 32

What is the correct electrode placement for the chest?

Answer 32

V1: Fourth intercostal space on the right sternum V2: Fourth intercostal space at the left sternum V3: Midway between placement of V2 and V4 V4: Fifth intercostal space at the midclavicular line V5: Anterior axillary line on the same horizontal level as V4 V6: Midaxillary line on the same horizontal level as V4 and V5

Question 33

What color is the earth electrode?

Answer 33

It is black

Question 34

What is important to know about electrode placement on the limbs vs the chest?

Answer 34

The chest electrode placement must be accurate by the limb electrode placement can vary within the given position

Question 35

In what state should the patient be when receiving an ECG?

Answer 35

The patient should be warm and relaxed

Question 36

What machine settings are standard for an ECG machine?

Answer 36

Paper speed of 25mm/second Voltage calibration should be set so that 1mV causes 1cm of upwards deflection

Question 37

What important information should be recorded on the ECG?

Answer 37

The date, time and patient’s name

Question 38

What important medical information should be recorded on the ECG?

Answer 38

The patient’s symptoms and BP on the ECG.

Question 39

What is the mechanism of a heartbeat in a normal heart?

Answer 39

In a normal heart, the sinoatrial node fires regularly and the electrical impulse spreads through an anatomical path to the ventricles resulting in ventricular contractions felt as the pulse or heartbeat

Question 40

What is a heart beat represented by on an ECG?

Answer 40

Each heartbeat is represented by one ECG complex

Question 41

How many parts does an ECG complex have?

Answer 41

An ECG complex consists of 5 parts?

Question 42

What does the P wave of the ECG complex represent?

Answer 42

The P wave represents electrical activation of the atrial muscle

Question 43

What is a term for the activation of the atrial muscle represented by the P wave?

Answer 43

It is called depolarization

Question 44

What is the PR interval in an ECG complex?

Answer 44

The time taken for the electrical impulse to spread from the atria to the ventricles through the atrioventricular node and the high speed conducting pathway called the bundle of His.

Question 45

What is the QRS complex in the ECG complex?

Answer 45

The QRS complex records the impulse spreading through the ventricles resulting in the ventricular contraction known as a heartbeat.

Question 46

In a normal heart, how many squares does it take to record the QRS complex?

Answer 46

It takes 3 small squares on an ECG

Question 47

What is the ST segment of the ECG complex?

Answer 47

The ST complex of the ECG complex is the period when the ventricles are completely activated

Question 48

What is the T wave of the ECG complex?

Answer 48

The T wave of the ECG complex is the return of the ventricular muscle to its resting electrical state.

Question 49

What is another term for the T wave of the ECG Complex?

Answer 49

Repolarization

Question 50

How is a normal heartbeat represented in the ECG complex?

Answer 50

A normal heartbeat is represented by one P wave, followed by one QRS complex and then one T wave.