ECGs

Question 1

What does the P wave represent and how long should it normally be?

Answer 1

Atrial depolarisation
Should be around max 12 ms (3 squares)

https://lms.rn.com/courses/2076/page13595.html see for ecg tests

Question 2

In which lead is the p wave negative or inverted?

Answer 2

AVR

Question 3

Peaks in the p wave suggest what and why might this arise?

Answer 3

Atrial hypertrophy due to:

Valvular disease
COPD
Pulmonary embolism
Heart failure

Question 4

What might an inverted p wave suggest?

Answer 4

Reverse conduction from Av junction to atria

Question 5

What do absent p waves suggest?

Answer 5

Conduction bypasses the SAN node, so could be atrial fibrillation or junctional rhythm

Question 6

What is junctional rhythm?

Answer 6

When the impulse starts in the bundle of His/AV node

Question 7

What would junctional rhythm look like on an ECG?

Answer 7

Absent p waves
Inverted p waves followed by QRS complex (this may be obscured by the T wave or QRS complex)

Question 8

What is the PR interval and where is it drawn from?

Answer 8

The time it takes for the impulse to go from the atria to the AV node
Start of P wave to start of R wave

Question 9

Normal duration of a PR interval?

Answer 9

120-200ms (3-5 small squares)

Question 10

What would a short PR interval of less than 120ms suggest?

Answer 10

That the impulse generated from someone other than the SAN. Could be a junctional arrhythmia or pre-excitation syndrome.

Question 11

What would a long PR interval of more than 200ms suggest?

Answer 11

Conduction block due to:
-digoxin toxicity
-heart block

Question 12

What is the normal duration of the QRS complex?

Answer 12

Half the time of the PR interval, so 60-100ms (0.06-0.10s)

about 2 small squares

Question 13

The QRS should be negative in which leads?

Answer 13

Leads V1-3 and aVR

Question 14

An inferior wall infarct would be due to which artery?

Answer 14

Right coronary artery

Question 15

Which leads would be affected in inferior wall infarct?

Answer 15

Leads 2, 3, aVF

Question 16

Which artery would cause anterior wall defect?

Answer 16

LAD

Question 17

Which leads would be affected if the left anterior descending artery was affected?

Answer 17

Leads V1-V4

Question 18

Which artery would cause lateral wall infarction?

Answer 18

Left circumflex

Question 19

Which leads would be affected if the left circumflex artery was affected?

Answer 19

Leads 1, aVL, v5 and v6

Question 20

What would cause posterior wall defect?

Answer 20

Posterior descending artery

Question 21

Which leads would be affected in posterior wall problem? What would be seen on an ECG?

Answer 21

Tall R wave and ST elevation in leads V1-3

Question 22

Which leads are related to the lateral part of the heart?

Answer 22

Lead 1
AVL
V5-v6

Question 23

Which leads are related to the inferior part of the heart?

Answer 23

Lead 2, 3
AVF

Question 24

Which leads are the anterior or septal leads?

Answer 24

V1-V4

Question 25

Axis deviation

Answer 25

lead 1 and 2 if lead 1 is up and lead 2 is down, it's left axis deviation if lead 1 is down but lead 2 is up, it's right axis deviation

Question 26

What is the p was really high?

Answer 26

P pulmonale, due to cor pulmonale

Question 27

If the third heart block was above the bundle of his, what does the QRS complex like?

Answer 27

Narrow complex

Question 28

If the third heart block was below the bundle of his, what does the QRS complex like?

Answer 28

Wide complex

Question 29

Differentiate between LBBB and RBBB

Answer 29

LEFT = WiLLiaM RIGHT = MaRRoW Look at V1 and V6 If the QRS complex is under the isoelectric line and looks like a W in V1, and then is above the isoelectric line and looks like an M in V6, it's LEFT bundle branch block If the opposite, it's RBBB

Question 30

What would wide, big Q waves suggest?

Answer 30

Previous MI - pathological Q waves

Question 31

What would be seen in HYPERkalemia?

Answer 31

Tented T waves Flat P waves Broad QRS and bradycardia

Question 32

Treatment for hyperkalemia?

Answer 32

10ml, 10% calcium gluconate 10U insulin (causes cells to take up potassium) 50mL, 50% dextrose ( stop them from having a hypo from the insulin)

Question 33

Hypokalemia ECG changes

Answer 33

U waves ST depression Prolonged QT interval

Question 34

QR interval in males and females?

Answer 34

Men <0.44s Women <0.46s

Question 35

QT interval calculation

Answer 35

T wave shouldn't be half way through the two R waves

Question 36

Causes of prolonged QT?

Answer 36

Acquired: Hypomagnsia hypokalemia COngenital ??????

Question 37

What could cause tall tented T waves?

Answer 37

Hyperkalemia Hyperacute MI

Question 38

What do you call a sloping QRS complex and what does it suggest?

Answer 38

Delta wave Wolf Parkinson White syndrome