ECG

Question 1

When to undertake an ECG

Answer 1

chest pains
back pain
shortness of breath
falls
older people
woman complaining of chest pain
Abdominal/Epigastric pain
electrical burns

Question 2

where are you placing limb electrodes

Answer 2

red lead goes to right shoulder
Yellow goes to left shoulder
Black goes to the right hip
Green goes to the left hip

Question 3

What is lead one

Answer 3

aVR

Question 4

What is lead two

Answer 4

aVL

Question 5

What is lead three

Answer 5

aVF

Question 6

Why is it that we mostly look at lead 2

Answer 6

it follows the conduction of the heart

Question 7

What is the p wave

Answer 7

Atrial depolarisation

Question 8

What is the QRS wave

Answer 8

ventricles depolarisation

Question 9

What is the t wave

Answer 9

Ventricular repolarisation

Question 10

what are the limb lead views

Answer 10

Lead 1 looks towards the left aspect of left ventricles

lead 2 looks towards the inferior portion of the heart LV

lead 3 looks towards the inferior left and Right ventricles

aVr looks at the right upper portion of the heart

aVL: looks towards the left upper portion of the heart.

aVF: looks towards the inferior portion of the heart.

Question 11

What does the ecg print at

Answer 11

prints at 25 mm per second
5 big squares = 25 mm = 1 sec
30 big squares = 6 sec
5 small square = 5mm =0.2 sec or 200 ms
1 small square = 1mm =0.04 sec

Question 12

PR intervals

Answer 12

PR interval start of atrial depolarization to the start of ventricle depolarization 3 - 5mm

Question 13

QT interval

Answer 13

Is the start of ventricle depolarisation to the end of ventricular repolarisation 11mm in men 11.5mm in woman

Question 14

ST seagment interval

Answer 14

end of ventricular depolarisation to the start of ventricular repolarisation​

Question 15

RR interval

Answer 15

bewteen each complex

Question 16

QRS interval

Answer 16

2 - 2.5 mm

Question 17

What are the different types of ventricle complexes

Answer 17

q wave = first negative deflection
r wave = first positive deflection
s wave = deflection following q wave

Question 18

how to calcualte heart rate

Answer 18

300 divided by the number of big sqaures within PR interval.

Question 19

chest leads placement

Answer 19

v1 - 4 intercostal space right
v2 - 4 intercostal space left
v3 - bewteen v2 and v4
v4 -5 intercostal space mid clavicular line
v5 - bewteen v4 and v6
v6 - mid axillar line

Question 20

what are the 10 rules of ecg the first rule

Answer 20

1.The pr interval bewteen 0.12 & 0.2 sec 3-5 small squares

Question 21

what are the 10 rules of ecg the second rule

Answer 21

The QRS duartion is ^ 0.11 sec 3 small sqaures

Question 22

what are the 10 rules of ecg the third rule

Answer 22

The QRS complex should be predominately upheld upright in leads 1 & 2

Question 23

what are the 10 rules of ecg the fourth rule

Answer 23

QRS &T waves tend to have the same general direction in the limb area

Question 24

what are the 10 rules of ecg the fifth rule

Answer 24

Confirm that aVR is negative

Question 25

what are the 10 rules of ecg the sixth rule

Answer 25

The R wave in the precordial leads must grow from v1 to at least v4

Question 26

what are the 10 rules of ecg the seventh rule

Answer 26

The ST segment should start isoelectric except in v1 and v2 where it may be slightly elevated

Question 27

what are the 10 rules of ecg the eight rule

Answer 27

The P wave should be upright in 1,2,v2 to v6

Question 28

what are the 10 rules of ecg thet nineth rule

Answer 28

There should be no Q waves - 0.04 sec 1 small sqaure in width in 1,2,v2 to v6

Question 29

what are the 10 rules of ecg the first rule

Answer 29

The T wave must be upright in 1,2,v2 to v6

Question 30

What are the guidelines on Stemi

Answer 30

to have 1mm in two leads with st segment elevation either I & aVL or II & III or V2 - V4

≥ 2.5 mm in men < 40 years (V2 & V3), ​

≥2 mm in men ≥ 40 years (V2 & V3), ​

≥ 1.5 mm in women (V2 & V3)​

or​

≥ 1 mm in all other leads (except V4/7/8/9)

Question 31

What is a anterior STEMI

Answer 31

ECG changes include ST elevation in V1 – V4​

Reciprocal changes in inferior leads

Question 31

what is inferior STEMI

Answer 31

ECG changes include ST elevation in II, III & aVF​

Reciprocal changes in aVL and sometimes I. but in inferior u need to do a V4R.​Move V4 to the right hand side (5th intercostal space (right) mid clavicular).​

​ST segment elevation of 0.5mm or more is positive. This indicates an Inferior MI with Right Ventricular Involvement.​

Question 32

What is a lateral STEMI

Answer 32

CG changes include ST elevation in 1, aVL, V5 – V6​.Reciprocal changes in inferior or anterior leads.Vasculature affected is the Circumflex (or LCA)​

Question 33

What is 1st degree heart block

Answer 33

PR interval > 200 ms (> 0.2 seconds or > 5 mm)​.Does not cause symptoms​

Caused by delay to AVN transmission, due to following:​
Increased vagal tone​,Ischaemia ,Athletic heart​t,AVN blocking drugs​

Question 34

What is 2nd degree heart block: type 2

Answer 34

Intermittent non-conducted P waves​.PR interval does not increase.Failure of the conduction system caused by structural damage, e.g. necrosis​.Also caused by electrolyte imbalance, surgery, medications.​

More likely to be haemodynamically unstable and transition into complete HB, asystole/ SCA.​

Question 35

What is 2nd degree heart block type 1

Answer 35

​Prolongation of PR interval until a QRS is dropped​.Usually does not cause haemodynamic instability ​

Due to AVN suppression (fatigued AV Nodal cells or increased vagal tone)​

Other causes include medications, inflammation, ischaemia and surgery​