The Cardiac Cycle pt.2.

Question 1

What are heart sounds generated by?

Answer 1

occur due to turbulence in blood flow

Question 2

What are the four physiological heart sounds?

Answer 2

1st = closure of the AV (mitral and tricuspid) valves

2nd = closure of the semi-lunar (aortic and pulmonary) valves

3rd = rapid passive filling phase

4th = active filling phase

Question 3

What are additional heart sounds called?

Answer 3

murmurs (physiological or pathological)

Question 4

What is the first heart sound?

Answer 4

mitral and tricuspid valves closing
-followed by systole

Question 5

What is second heart sound?

Answer 5

aortic and pulmonary valves closing
- followed by diastole

Question 6

What are additional sounds during systole called?

Answer 6

Systolic murmur - could be cause of
Stenosis of aortic/pulmonary valves or
Regurgitation through mitral/tricuspid valves

Question 7

What can diastolic murmur be caused by?

Answer 7

-Stenosis of mitral/tricuspid valves or
Regurgitation through aortic/pulmonary valves

Question 8

What is a continous murmur?

Answer 8

can be heard thorughout both and could be caused by patent ductus arteriosus

Question 9

What is the ductus arteriosus?

Answer 9

small vessel that joins the aorta to the pulmonary trunk during development .
Supposed to close after birth and if it doesn’t can lead to patent ductus arteriosus.

Question 10

Describe patent ductus arteriousus?

Answer 10

pressure in aorta is higher than pressure in pulmonary trunk and therefore some blood will continually flow from aorta into pulmonary trunk.