Module 3 Formative Quiz

Question 1

A diastolic murmur, coincident with an increased preload, would likely be caused by

Answer 1

Aortic regurgitation

Question 2

Which of the following is the effect of parasympathetic stimulation of heart rate

Answer 2

Ach decreases K+ current during phase 3

Question 3

Which of the following pair points represents the period t which ventirucler volume is decreasing

Answer 3

C to D

Question 4

Point C is the point on the LV/PV loop that best appropriates its the bet index of which of the following

Answer 4

Aortic diastolic pressure

Question 5

Increasing the vagal stilumation to the heart will instantly cause in increase in the

Answer 5

RR interval (from a standard electrocardiogram)

Question 6

During the isovolumetric contractio phase of one cardiac cycle, the AV valves are ________ and the aortic and semilunar valves are _________

Answer 6

closed
closed

Question 7

Which of the following is a compensatory response to the blood loss, say from an acute moedrate hemorrhage

Answer 7

Decreased cardiac interbeat interval

Question 8

Which of the following is the most effective in maintaining preload in response to hemorrhage?

Answer 8

venoconstriction

Question 9

Which of the following exacerbates hypotension during the response to hemorrhage?

Answer 9

Tissue hypoxia

Question 10

Which of the following drugs is most likely to decrease heart rate by its action on the effective refractory period?

Answer 10

K+ channel antagonist

Question 11

The causal relationship between the severe loss of circulating volume and the subsequent drop in blood pressure is best characterized by the ______________.

Answer 11

Reduction in venous return

Question 12

Evaluate the image above. The black curve (wide) is normal and the red curve (narrow) represents the subsequent ventricular cycle.

Which event below is most likely the cause of the change in ventricular output?

Answer 12

Increased afterload

Question 13

An increase in arteriolar resistance, without any change in any other component of the cardiovascular system, is most expected to produce ______.

Answer 13

An increase in arterial pressure

Question 14

The elasticity of the walls of the arteries is important because

Answer 14

It maintains arterial blood pressure during diastole

Question 15

Assume that left ventricular end diastolic volume (LVEDV) is 100 ml and that left atrial contraction contributes 20% of LVEDV. If left ventricular reserve volume (end-systolic) is 25 ml, what accounts for the ‘other’ 55 ml of LVEDV?

Answer 15

Slow passive ventricular filling (diastasis)

Question 16

The discharge rate of action potentials traveling from the carotid baroreceptors to the medulla is _________ to the change in mean arterial pressure. In response to a decrease in mean arterial pressure, one would expect increases in heart rate and contractility, mediated by the _______________branch of the autonomic nervous system

Answer 16

Proportional
sympathetic

Question 17

Reflex control of blood pressure in mammals is critically dependent upon the integrity and direct interaction among the following three things: (1) baroreceptors, (2) cranial nerves, and (3) which medullary constituent?

Answer 17

The nucleus tractus solitarius

Question 18

Calculate Cardiac output given any/some of the following date: stroke volume is 50 ml/beat, systolic pressure 120 mm Hg, diastolic pressure 75 mm Hg, beat frequency = 72 b/m, and Hct = 45%.

Answer 18

3600 ml/min

Question 19

Stroke volume is expected to be greatest when ______________.

Answer 19

there is an increase in preload

Question 20

Ejection fraction (EF) = SV/EDV. A decrease in EF is most likely associated with _____________________

Answer 20

Systolic dysfunction

Question 21

During the isovolumic contraction phase of the left ventricle ________________

Answer 21

Aortic pressure decreases

Question 22

An increase in stroke volume, without any change it inotropy, is expected when ________________.

Answer 22

Preload increases

Question 23

Which option represents the ‘best index’ of end-diastolic volume?

Answer 23

preload

Question 24

When left-ventricular pressure becomes less than left atrial pressure the mitral valve is __________________

Answer 24

open

Question 25

Approximate the ejection fraction given the following data: HR = 74 bpm, cardiac output = 4.5 L/min, LVEDV = 120 ml, Stroke volume = 65 ml, BP = 120/79 mm Hg.

Answer 25

55%

Question 26

A prolapsed aortic semilunar valve would be expected to have what effect on left-ventricular end systolic volume?

Answer 26

increase

Question 27

Predict which class of drug would be least likely to directly alter the cardiac chronotropic state in a patient with primary autonomic failure.

Answer 27

alpha adrenergic agonist

Question 28

Sympathetic stimulation to the heart causes the release norepinephrine which binds ______ resulting in a _______ in contractility.

Answer 28

Beta 1 receptors and increases

Question 29

What does it mean that “IV dobutamine has rapid onset and fast-elimination kinetics”?

Answer 29

it has low VD, short elimination T1/2, and high clearance rat

Question 30

Which of the effects is least expected of IV dobutamine administration?

Answer 30

decreased myocardial contractality

Question 31

Dobutamine increases cardiac contractility due to its _______________.

Answer 31

B1 adrenergic receptor agonism