18. The Heart

Cardiac Cycle

Open Question
What is cardiac output, and how is it calculated?
Open Question
You have been called upon to demonstrate the technique for listening to valve sounds.a. Explain where you would position your stethoscope to auscultate (1) the aortic valve of a patient with severe aortic valve insufficiency and (2) a stenotic mitral valve.b. During which period(s) would you hear these abnormal valve sounds most clearly? (During atrial diastole, ventricular systole, ventricular diastole, or atrial systole?)c. What cues would you use to differentiate between an insufficient and a stenotic valve?
Open Question
Harvey has a heart murmur in his left ventricle that produces a loud 'gurgling' sound at the beginning of systole. Which valve is probably faulty?
Open Question
Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

a. Systole is the contraction portion of the cardiac cycle and diastole is the relaxation portion.
Open Question
Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

b. Atrial systole is responsible for ejecting most of the blood into the ventricles during the ventricular filling phase of the cardiac cycle.
Open Question
Which chamber generates the highest pressure during systole?

a. Right atrium
b. Right ventricle
c. Left atrium
d. Left ventricle
Open Question
Fill in the blanks: The first heart sound is called______and it is caused by the closing of the_____valves. It occurs at the beginning of the_____phase of the cardiac cycle. The second heart sound is called_____and it is caused by the closing of the______ valves. It occurs at the beginning of the_____phase of the cardiac cycle.
Open Question
Cardiac output is equal to:

a. end-diastolic volume minus end-systolic volume.
b. heart rate multiplied by stroke volume.
c. stroke volume divided by end-diastolic volume.
d. heart rate multiplied by preload.
Open Question
Fill in the blanks: An increase in preload causes a/an_____ in stroke volume in accordance with the_____ law. An increase in afterload causes a/an ______in stroke volume. An increase in contractility causes a/an______in stroke volume.
Open Question
Which of the following statements is false?

a. The sympathetic nervous system releases epinephrine and norepinephrine, which are positive chronotropic and inotropic agents.
b. The endocrine system regulates cardiac output through chronotropic and inotropic hormones and through hormones that regulate water balance.
c. The parasympathetic nervous system releases acetylcholine and epinephrine, which are strongly negative inotropic agents.
d. Factors such as electrolyte concentrations, body temperature, and age all affect cardiac output.
Open Question
You are an athletic trainer who is working with someone planning to run a marathon. Your trainee tells you to give him a workout that will make his heart 'beat faster than ever before.' What do you tell him about the effects of too rapid a heart rate?
Multiple Choice
A doctor puts his stethoscope on a patient's chest over the location of the heart and hears an abnormal swishing sound. Which of the following conditions is the best diagnosis for the patient's condition?
Open Question
Multiple ChoiceMore than one choice may apply.Given a volume of 150 ml at the end of diastole, a volume of 50 ml at the end of systole, and a heart rate of 60 bpm, the cardiac output isa. 600 ml/min.b. 6 liters/min.c. 1200 ml/min.d. 3 liters/min.
Open Question
a. Describe how heart contraction and relaxation influence coronary blood flow.b. Name the major branches of the coronary arteries, and note the heart regions served by each.
Open Question
Freshly oxygenated blood is first received by thea. atrium,b.atrium, c. right ventricle, d. left ventricle.