Session 2

Question 0

Name the two outflow valves

Answer 0

Pulmonary and aortic

Question 1

Name the two atrioventricular valves

Answer 1

Cuspid and mitral

Question 2

What is systole?

Answer 2

The period when the myocardium is contracting

Question 3

Describe the spread of excitation

Answer 3

Action potential generated in pacemaker cells in SA node of the right atrium
Activity spreads over the atria - atrial systole - to the atrio-ventricular node
Delayed here for 120ms
Spreads down septum
Through ventricular myocardium form endo- to epicardial surface
Ventricles contract from apex up

Question 4

What is equation for cardiac output? Units?

Answer 4

Stroke volume x heart rate

Litres/minute

Question 5

What is the LUP sound?

Answer 5

Closure of AV valves

Question 6

What is the DUP sound?

Answer 6

Closure of outflow valves

Question 7

What is the time interval between the first and second sounds?

Answer 7

280ms

Question 8

What is the time intervals between the second and first sound?

Answer 8

700ms

Question 9

What is a heart murmur?

Answer 9

Turbulent flow of blood

Question 10

What is stenosis?

Answer 10

A narrowed valve

Question 11

When would an aortic stenosis produce a murmur?

Answer 11

During the rapid ejection phase

Would hear LUP-whoosh-DUP

Question 12

What is incompetence?

Answer 12

When the valves do not close properly

Question 13

What are the causes of a heart murmur?

Answer 13

Stenosis of a valve

Valves not closing properly

Question 14

What initiates the action potential in the heart?

Answer 14

Spontaneous depolarisation of the pacemaker cells

Question 15

How much blood is ejected per beat at rest by the left ventricle?

Answer 15

75-80 ml

Question 16

At what pressure does blood flow to the pulmonary artery?

Answer 16

20 mmHg

Question 17

How long in ventricular systole?

Answer 17

300 ms

Question 18

What is the approximate duration of diastole if the heart is beating at 60bpm?

Answer 18

700ms