230
CARDIOVASCULAR PHYSIOLOGY CONCEPTS
One important reason why stroke vol-
ume is able to increase during running
exercise is that
a. Central venous pressure decreases.
b. Heart rate increases.
c. The rate of ventricular relaxation
decreases.
d. Venous return is enhanced by the
muscle pump system.
In an exercise study, the subject’s resting
heart rate and left ventricular stroke
volume were 70 beats/min and 80 mL/
beat, respectively. W hile the subject was
walking rapidly on a treadmill, the heart
rate and stroke volume increased to
140 beats/min and 100 mL/beat, respec-
tively; ejection fraction increased from
60% to 75%. The subject’s mean arterial
pressure increased from 90 mm Hg at
rest to 110 mm Hg during exercise. One
can conclude that
a. Cardiac output doubled.
b. Compared to rest, the cardiac output
increased proportionately more dur-
ing exercise than systemic vascular
resistance decreased.
6.
Long-term recovery of cardiovascular
homeostasis following moderate hemor-
rhage involves
a. Aldosterone inhibition of renin
release.
b. Enhanced renal loss (excretion) of
sodium.
c. Increased capillary fluid filtration.
d. Vasopressin-mediated water reabsorp-
tion by the kidneys.
7.
A trauma patient is admitted the Emer-
gency Department follow ing massive
blood loss. The bleeding is controlled,
and resuscitation with fluids and pres-
sor agents elevates the mean arterial
pressure to 60 mm Hg. Despite addi-
tional efforts to raise arterial pressure,
the pressure begins to fall after 2 hours,
and the patient dies. W hich of the fol-
low ing m ost likely contributed to the
cardiovascular collapse in this patient?
a. Excessive fluid sodium and water
retention by the kidneys
b. Increased capillary fluid reabsorption
c. Myocardial depression by metabolic
acidosis
2.
3.
c. Ventricular end-diastolic volume
increased.
d. The increase in mean arterial pressure
during exercise indicates that sys-
temic vascular resistance increased.
4.
During the second trimester of preg-
nancy,
a. Systemic vascular resistance is
increased.
b. Heart rate is decreased.
c. Cardiac output is decreased.
d. Blood volume is increased.
5.
The baroreceptor reflex in hemorrhagic
shock
a. Decreases venous compliance.
b. Decreases systemic vascular resist-
ance.
c. Increases vagal tone on the SA node.
d. Stimulates angiotensin II release from
the kidneys.
d. Sympathetic-mediated vasoconstric-
tion
8.
A 43-year-old female patient consistently
has arterial pressure values of about
150/105 mm Hg. This patient’s hyperten-
sion could be the result of
a. Diminished secretion of aldosterone.
b. Excessive renal excretion of sodium.
c. Suppressed release of renin.
d. Thyroid disorder.
9.
The echocardiogram report that you
receive for your patient indicates that he
has left ventricular diastolic dysfunction.
W hich of the following is usually associ-
ated with this condition?
a. Increased ventricular compliance
b. Elevated end-diastolic pressure
c. Decreased end-systolic volume
d. Large decrease in ejection fraction
previous page 243 Cardiovascular Physiology Concepts  2nd Edition read online next page 245 Cardiovascular Physiology Concepts  2nd Edition read online Home Toggle text on/off