Q: Calculate the cardiac output (CO) for a patient with a heart rate (HR) of 90 beats/min and a stroke volume (SV) of 60 mL/beat. Use the formula $$CO = HR \times SV.$$

$$CO = 90 \times 60 = 5400\ \text{mL/min}$$

Q: A patient has a heart rate of 80 beats/min, an end diastolic volume (EDV) of 130 mL, and an end systolic volume (ESV) of 60 mL. What is the stroke volume (SV) and cardiac output (CO)? Use $$SV = EDV - ESV$$ and $$CO = HR \times SV.$$

$$SV = 70\ \text{mL},\ CO = 5600\ \text{mL/min}$$

Question 1

Which of the following best describes the function of the pericardial fluid found in the pericardial cavity?

Accepted Answer

It lubricates the heart, reducing friction as the heart beats.

Question 2

A patient is diagnosed with pericarditis, which causes the pericardial membranes to become inflamed. What is a likely consequence of this condition?

Accepted Answer

Friction rub and chest pain due to the heart rubbing against the pericardial sac.

Question 3

Which of the following correctly matches a heart chamber with the blood vessel that delivers blood to it?

Accepted Answer

Left atrium – pulmonary veins

Question 4

During ventricular systole, which valves are open and which are closed?

Accepted Answer

AV valves are closed; SL valves are open.

Question 5

A patient has a stenotic aortic valve. What effect does this have on blood flow and heart sounds?

Accepted Answer

Blood flow through the aorta is restricted, causing a murmur during ventricular systole.

Question 6

Which of the following best explains the Frank-Starling law of the heart?

Accepted Answer

The greater the preload (stretch of cardiac muscle), the greater the force of contraction and stroke volume.

Question 7

Calculate the cardiac output (CO) for a patient with a heart rate (HR) of 90 beats/min and a stroke volume (SV) of 60 mL/beat. Use the formula $$CO = HR 	imes SV.$$

Accepted Answer

$$CO = 90 	imes 60 = 5400\ 	ext{mL/min}$$

Question 8

Which of the following is a direct effect of sympathetic stimulation on the heart?

Accepted Answer

Increased heart rate and contractility

Question 9

A patient presents with left-sided heart failure. Which of the following symptoms is most likely to occur?

Accepted Answer

Pulmonary congestion and edema

Question 10

Which of the following best describes the role of gap junctions in cardiac muscle tissue?

Accepted Answer

They allow ions to pass directly between cells, enabling coordinated contraction.

Question 11

Which event is represented by the QRS complex on an electrocardiogram (ECG)?

Accepted Answer

Ventricular depolarization

Question 12

A patient has a heart rate of 80 beats/min, an end diastolic volume (EDV) of 130 mL, and an end systolic volume (ESV) of 60 mL. What is the stroke volume (SV) and cardiac output (CO)? Use $$SV = EDV - ESV$$ and $$CO = HR 	imes SV.$$

Accepted Answer

$$SV = 70\ 	ext{mL},\ CO = 5600\ 	ext{mL/min}$$

Question 13

Which of the following best explains why the left ventricle has a thicker wall than the right ventricle?

Accepted Answer

It pumps blood to the systemic circuit, which requires more force.

Question 14

Which of the following is a correct sequence of blood flow through the heart and lungs?

Accepted Answer

Right atrium → right ventricle → pulmonary trunk → lungs → left atrium

Question 15

Which of the following would most likely result from a myocardial infarction (heart attack)?

Accepted Answer

Replacement of dead cardiac tissue with scar tissue

Question 16

Which of the following best describes the function of the chordae tendineae?

Accepted Answer

They anchor the atrioventricular valves to the papillary muscles, preventing valve prolapse.

Question 17

A patient is experiencing ventricular fibrillation. What is the most immediate danger of this condition?

Accepted Answer

The heart is unable to pump blood effectively, leading to loss of circulation.

Question 18

Which of the following statements about the intrinsic cardiac conduction system is correct?

Accepted Answer

It initiates and distributes electrical impulses to coordinate heart contraction.

Question 19

Which of the following would most likely increase stroke volume (SV)?

Accepted Answer

Increased preload (greater stretch of cardiac muscle)

Question 20

Which of the following best explains why hyperkalemia (elevated potassium) can be life-threatening for heart function?

Accepted Answer

It disrupts the pacemaker potential, potentially leading to arrhythmias.

The Cardiovascular System: The Heart (Chapter 18 Study Notes)

Guida di studio - Domande di pratica

Study guide - Flashcard