Week 1 - Introduction to the CVS, Histology of the CVS

Question 1

Describe the Korotkoff sounds.

Answer 1

The Korotkoff sounds are used to describe the sounds auscultated over the brachial artery during sphygmanometry.

1st sound: Cuff pressure reduced to below systolic pressure, which generates turbulent flow in the brachial artery - this indicates systolic blood pressure

5th sound: Cuff pressure reaches diastolic pressure and sounds disappear as turbulent flow stops

Question 2

Outline the finding on auscultation for aortic valve stenosis (sound heard).

Answer 2

Ejection systolic murmur

Question 3

In which type of blood vessel is the minimum velocity found? Why?

Answer 3

The speed of blood flow in vessels is inversely proportional to their cross-sectional area. The entire capillary bed (very large cross-sectional area) must transmit the same blood flow (=speed x cross-sectional area) as the aorta. Therefore, velocity must fall as cross-sectional area increases. Blood flow (volume/time) is the same in the vena cava and aorta, despite lower pressure in the vena cava.