$CO = 90 \times 60 = 5400\,ml/min$

Question 1

Which of the following best describes the relationship between preload and stroke volume according to the Frank-Starling law?

Accepted Answer

As preload increases, stroke volume increases due to more optimal overlap of actin and myosin filaments.

Question 2

A patient has an end-diastolic volume (EDV) of 130 ml and an end-systolic volume (ESV) of 60 ml. What is their stroke volume (SV)?

$SV = EDV - ESV$

Accepted Answer

$SV = 130\,ml - 60\,ml = 70\,ml$

Question 3

Which of the following would most likely increase cardiac output (CO)?

$CO = HR 	imes SV$

Accepted Answer

An increase in both HR and SV

Question 4

Which factor is most directly responsible for determining the afterload of the left ventricle?

Accepted Answer

The pressure in the systemic circuit

Question 5

A drug acts as a positive inotropic agent. What effect will it have on the heart?

Accepted Answer

It will increase the heart's contractility and raise stroke volume.

Question 6

If a patient’s heart rate is 90 beats/min and their stroke volume is 60 ml/beat, what is their cardiac output?

$CO = HR 	imes SV$

Accepted Answer

$CO = 90 	imes 60 = 5400\,ml/min$

Question 7

Which of the following scenarios would most likely result in a decreased stroke volume?

Accepted Answer

Decreased preload, decreased contractility, and increased afterload

Question 8

Which hormone would most likely increase cardiac output by increasing blood volume and preload?

Accepted Answer

Aldosterone

Question 9

A patient with left ventricular failure is most likely to develop which of the following complications?

Accepted Answer

Pulmonary edema due to backup of blood in the pulmonary circuit

Question 10

Which of the following is a negative chronotropic agent?

Accepted Answer

Parasympathetic nervous system stimulation

Question 11

During vigorous exercise, which of the following changes would you expect in the heart?

Accepted Answer

Increased preload, increased contractility, and increased cardiac output

Question 12

Which of the following best explains why ventricular hypertrophy can be harmful in the long term?

Accepted Answer

It decreases the heart's lumen and filling space, increasing the risk for heart failure.

Question 13

Which of the following would most likely occur if the afterload on the left ventricle increases significantly?

Accepted Answer

Stroke volume decreases and ESV increases.

Question 14

Which of the following is the correct formula for ejection fraction (EF)?

Accepted Answer

$EF = \frac{SV}{EDV}$

Question 15

A patient is given a drug that increases the rate at which the SA node fires. What is the most likely effect?

Accepted Answer

Positive chronotropic effect and increased heart rate

Question 16

Which of the following is a likely compensatory response by the kidneys during heart failure?

Accepted Answer

Increased fluid retention to raise preload

Question 17

Which of the following would be expected in a trained athlete at rest compared to an untrained individual?

Accepted Answer

Lower resting heart rate and higher stroke volume

Question 18

Which of the following is true regarding the effects of the parasympathetic nervous system on the heart?

Accepted Answer

It decreases heart rate and has only weak effects on contractility.

Question 19

A patient with high blood pressure in the pulmonary circuit is most likely to develop which cardiac adaptation?

Accepted Answer

Right ventricular hypertrophy

Question 20

Which of the following would most likely decrease cardiac output?

Accepted Answer

Decreased preload due to blood loss

Cardiac Output and Its Regulation

Study Guide - Practice Questions