CVS Physio Pt 2/2 (ECG n PE)

Question 1

What does ECG measure?

Question 2

(Using your hand actions) Show the “views” of Leads I, II, III and Leads aVR, aVL and aVF.

Question 3

Where are the 10 electrodes in 12-lead ECG placed?

Question 4

(i) Draw out the ECG 12 boxes strip.

(ii) Which ECG box corr to which leads? (draw the pattern on a pic of the ECG).

(iii) Which leads (thus which boxes) then corr to (eg. probs w) which coronary arteries?

Question 5

1 small box = ?s
1 big box (aka 5 small boxes) = ?s on ECG ppr

Question 6

Outline the cardiac cycle. (draw ‘pie chart’)

Note: the ELECTRICAL ACTIVITY during each cardiac cycle is represented as a graph on ECG ppr

Question 7

What does ‘ups’ - positive deflections and ‘downs’ - negative deflections mean in ECG ppr?

Question 8

Interpret what these mean:
(i) P wave
(ii) QRS complex
(iii) T wave

(iv) PR interval
(v) ST segment (“from end of S to start of T”)
(vi) QT interval (“from start of Q to end of T”)
(vii) RR interval

Answer 8

HINT: RMB THE WAVES, WTV YOU SEE ON ECG = ELECTRICAL ACTIVITY –> you can outline the direction location of the conduction system of heart (specialised muscle fibres transmitting these impulses)

Question 9

Does depolarisation or repolarisation give rise to systole?

Answer 9

depol –> systole

Question 10

Does depolarisation or repolarisation give rise to diastole?

Answer 10

repol –> diastole

Question 11

What’s the formula for using RR interval to calculate HR?

Answer 11

300/(no. of big sq btw RR)

Question 12

normal HR of 75bpm = ? big squares on ECG ppr

Answer 12

4

Question 13

Bradycardia = ? bpm = >? big squares on ECG ppr

Question 14

Tachycardia= ? bpm = <? big squares on ECG ppr

Question 15

Interpret what these mean:
1. missing P wave
2. prolonged PR interval
3. prolonged QRS interval
4. Tall QRS complex
5. prolonged QT interval (“from start of Q to end of T”)
6. Tall T wave
7. ST segment elevation (“from end of S to start of T”)
8. ST segment depression (“from end of S to start of T”)
9. Prolonged RR interval

Answer 15

IMPNOTE: rmb all these CG waves are the CONDUCTION SIGNALS in conduction syste of heart, not much of what muscular movement is happening - change perspective

Question 16

Explain how to calculate the patient’s cardiac axis to diagnose left/ right axis deviation of heart.
(Explain the steps!)

Question 17

Apex beat:
1. created by?
2. during __ systole
3. anatomical location on chest wall?
4. What do these mean:
- stronger amplitude of apex beat
- sustained apex beat
- laterally and inferiorly displaced apex beat
- absence of apex beat

Question 18

What does JVP represent?

Why can JVP be representative of RA pressure?

Question 19

Name the 3 waves and 2 descents in JVP graph. What do they each represent?

Question 20

What does:
(i) giant a wave
(ii) giant c wave
mean?

Question 21

When do the 2 normal heart sounds occur?
(^think wrt cardiac cycle pie chart)

When do the 2 abnormal heart sounds occur?

Question 22

What is:
(i) physiologic S2 splitting
(ii) pathologic S2 splitting
and when are they heard?

Question 23

What gives rise to murmurs?

Question 24

What does it mean (which valve got prob, and what fxnal prob) when there’s a systolic vs diastolic murmur?

Answer 24

Systolic murmur:
- mitral/ tricuspid regurg
- aortic/ pulmonary stenosis

Diastolic murmur:
- aortic/ pulmonary regurg

Question 25

Within the class of ‘systolic murmurs’, explain the 2 types:
(i) Ejection systolic murmur
vs
(ii) Pansystolic murmur

• when it happens in systole?
• what (fxnal valve defect(s)) causes it?

Answer 25

(i) Ejection systolic murmur
- happens during the second part of a systole – the ejection
- due to blood being squeezed through narrower lumen
- ^due to: aortic/ pulmonary STENOSIS

(Recall: systole = compress + eject)

(ii) Pansystolic murmur
- happens throughout systole (compress + eject)
- due to mitral/ tricuspid REGURGITATION

Question 26

What are heaves? What pathology allows you to hear heaves?

Question 27

What are thrills? What pathology allows you to hear thrills?