Question 1

The first of the two numbers measured when taking the blood pressure represents .

Accepted Answer

The first number in a blood pressure reading represents the systolic pressure, which is the pressure in the arteries when the heart beats and fills them with blood.

Question 2

The AV valves close when _.

Accepted Answer

The AV (atrioventricular) valves close when ventricular systole begins. This is because the pressure in the ventricles exceeds the pressure in the atria, preventing backflow of blood into the atria.

Question 3

AV valves are best auscultated at the .

Accepted Answer

The atrioventricular (AV) valves, which include the tricuspid and mitral valves, are best auscultated at the 5th intercostal space. The tricuspid valve area is best heard at the left lower sternal border (5th intercostal space), and the mitral valve area is best heard at the apex of the heart, which is also located in the 5th intercostal space but more medially, under the left breast.

Question 4

Venous pressure _.

Accepted Answer

Venous pressure is significantly lower than arterial pressure because veins are the vessels that return blood to the heart and operate at a lower pressure compared to arteries, which carry blood away from the heart under high pressure.

Question 5

The dichrotic notch is a result of pressure fluctuations that occurs when the aortic valve snaps shut. During which phase of the cardiac cycle can one observe the dichrotic notch?

Accepted Answer

The dichrotic notch is observed during isovolumetric relaxation, which occurs right after the aortic valve closes, marking the end of ventricular systole and the beginning of diastole. This closure causes a brief increase in aortic pressure, creating the notch on the aortic pressure curve.

Question 6

The mean arterial pressure for a patient whose blood pressure is 110/80 is _ _.

Accepted Answer

The mean arterial pressure (MAP) can be estimated with the formula: MAP ≈ diastolic pressure + 1/3(systolic pressure - diastolic pressure). For a blood pressure of 110/80, MAP ≈ 80 + 1/3(110 - 80) = 80 + 1/3(30) = 80 + 10 = 90 mm Hg.

Question 7

Pulse deficit _.

Accepted Answer

Pulse deficit is the difference between the apical and radial pulses. It occurs when all of the heartbeats do not reach the peripheral arteries or are too weak to be palpated, indicating a discrepancy between the heart's contractions and the pulse felt at the wrist.

Question 8

The first heart sounds are best heard .

Accepted Answer

The first heart sounds, associated with the closure of the atrioventricular valves (mitral and tricuspid valves), are best heard in the 5th intercostal spaces, at various distances from the sternal margins. This location corresponds to the anatomical position of the heart within the thoracic cavity, allowing for optimal auscultation of these sounds.

Question 9

When taking blood pressure, the sounds heard when the pressure cuff is released are due to .

Accepted Answer

The sounds heard when the pressure cuff is released during blood pressure measurement are due to turbulent blood flow. This occurs as blood starts to flow again through the compressed artery, creating audible vibrations known as Korotkoff sounds.

Question 10

During moderate exercise, .

Accepted Answer

During moderate exercise, both heart rate and blood pressure increase to supply the muscles with more oxygen-rich blood.

Quiz 33: Human Cardiovascular Physiology: Blood Pressure and Pulse Determinations