Cardiovascular

End-diastolic volume (EDV) for each ventricle at the end of atrial systole is normally about:

120 ml.

A patient has a heart rate of 70 beats per minute, an EDV of 110 ml, and an ESV of 70 ml. What is the patient's cardiac output?

2.8 L/minute

The amount of blood remaining in each ventricle at the end of the ventricular ejection phase is normally about:

50 ml.

Calculate the cardiac output if the heart rate is 100 beats per minute and the stroke volume is 65 ml.

6500 ml/min

How much blood is pumped from each ventricle during the ventricular ejection phase?

70 ml

Calculate the stroke volume (SV) of a patient whose EDV is 140 milliliters and whose ESV is 60 milliliters.

80 milliliters

Sometimes health care providers will elect not to treat conditions such as atrial fibrillation in which there is no functional atrial contraction. Select the logic behind this.

Most of the blood drains from the atria passively into the ventricles.

Predict the position of the valves during the ventricular ejection phase.

The AV valves are shut while both semilunar valves are forced open.

What best describes the Frank-Starling law?

The Frank-Starling law states that the more the ventricular muscle cells are stretched, the more forcefully they contract.

Which of the following happens immediately after the P wave?

The atria contract.

According to the Frank-Starling law, a bigger preload will result in __________.

a stronger contraction

Which of the following is a chronotropic agent that decreases heart rate?

acetylcholine

Inotropic agents affect:

contractility.

Which of the following is not an effect of the sympathetic nervous system?

decrease in heart rate

Hemorrhage would lead to a __________ preload and therefore __________ cardiac output.

decreased; decreased

The maximum amount of blood in the ventricles at the end of the ventricular filling phase is called __________.

end-diastolic volume

What largely determines preload?

end-diastolic volume (EDV)

Ventricular systole begins during the __________ phase of the cardiac cycle.

isovolumetric contraction

As ventricular systole begins, all four heart valves are closed during the:

isovolumetric contraction phase.

Which chamber experiences a maximum pressure of around 118 mm Hg during contraction?

left ventricle

The degree of stretch experienced by the sarcomeres in the ventricle cells before they contract is called:

preload.

The AV valves close when __________.

pressure in the ventricles increases

What two values are needed in order to calculate cardiac output (CO) for a ventricle?

stroke volume (SV) and heart rate (HR)

The volume of blood pumped by each ventricle in one heartbeat is known as:

stroke volume (SV).

Afterload is described as:

the force the ventricles must overcome to eject blood into their respective arteries.

The aortic valve closes when __________.

the pressure in the left ventricle falls below aortic pressure

What produces the "lub dub" heart sounds?

the vibrations of the ventricular and blood vessel walls when valves shut

Which cranial nerves have a negative chronotropic effect on heart rate?

vagus nerves (CN X)

The chambers that have just emptied when the second heart sound is heard are the __________.

ventricles

During what phase does blood flow from the ventricles into the pulmonary trunk and aorta?

ventricular ejection phase