NS - CVS III

Question 1

Why is more than one lead used to determine electrical activity?

Answer 1

Indicates a more detailed direction of impulse

Question 2

What does Einthoven’s triangel refer to?

Answer 2

A theoretical triangle formed by three limb leads on the surface of the body

Question 3

How do valves help with blood flow?

Answer 3

Give an efficient one way flow

Question 4

What is Sinus Arrhythmia?

Answer 4

Normal variation of the heart rhythm
- coincide with the respiratory cycle

Question 5

What is seen on the ECG when there is a defect at the SA node? (3)

Answer 5

1. Loss of P wave
2. Irregular beats
3. Slow heart rate

Question 6

What is seen on the ECG when there is a defect at the AV node (AV block 1 and 2)?

Answer 6

First degree AV block
* P-Q interval extended

Second degree AV block
* Full block after P wave

Question 7

What is seen on the ECG when there is a atrial and ventricular fibrilation?

Answer 7

AF
* No clear p waves
* Irrefular rhythm

VF
* No waves identifiable
* Chaotic rhythm

Question 8

What are the main 3 layers of blood vessels?

Answer 8

Intima

Media

Adventitia

Question 9

What is present in the Intima? (3)

Answer 9

• Endothelium
• Basal lamina
• Loose connective tissue

Question 10

What is present in the Media? (2)

Answer 10

• Smooth muscle
• Elastin fibres

Question 11

What is present in the Adventitia?

Answer 11

Collagen tissue

• Thick in arterioles
• Thin in venules