Pathophysiology: Chapter 34: Alterations of Cardiovascular Function in Children

Question 1

Most cardiovascular developments occur between which weeks of gestation?

a. Fourth and seventh weeks c. Twelfth and fourteenth weeks
b. Eighth and tenth weeks d. Fifteenth and seventeenth weeks

Answer 1

ANS: A
Cardiogenesis begins at approximately 3 weeks’ gestation; however, most cardiovascular
development occurs between 4 and 7 weeks’ gestation.

Question 2

The function of the foramen ovale in a fetus allows what to occur?

a. Right-to-left blood shunting c. Blood flow from the umbilical cord
b. Left-to-right blood shunting d. Blood flow to the lungs

Answer 2

ANS: A
The nonfused septum secundum and ostium secundum result in the formation of a flapped
orifice known as the foramen ovale, which allows the right-to-left shunting necessary for
fetal circulation. The foramen ovale is not involved in the blood flow described by the
other options.

Question 3

At birth, which statement is true?

a. Systemic resistance and pulmonary resistance fall.
b. Gas exchange shifts from the placenta to the lung.
c. Systemic resistance falls and pulmonary resistance rises.
d. Systemic resistance and pulmonary resistance rise.

Answer 3

ANS: B
From the available options, the only change that takes place in the circulation at birth is the
shift of gas exchange from the placenta to the lungs.

Question 4

When does systemic vascular resistance in infants begin to increase?

a. One month before birth
b. During the beginning stage of labor
c. One hour after birth
d. Once the placenta is removed from circulation

Answer 4

ANS: D
The low-resistance placenta is removed from circulation, which causes an immediate
increase in systemic vascular resistance to approximately twice of that before birth.

Question 5

Which event triggers congenital heart defects that cause acyanotic congestive heart
failure?
a. Right-to-left shunts c. Obstructive lesions
b. Left-to-right shunts d. Mixed lesions

Answer 5

ANS: B
Congenital heart defects that cause acyanotic congestive heart failure usually involve
left-to-right shunts (see Table 33-4). Acyanotic congestive heart failure does not involve
any of the other options.

Question 6

Older children with an unrepaired cardiac septal defect experience cyanosis because of
which factor?
a. Right-to-left shunts c. Obstructive lesions
b. Left-to-right shunts d. Mixed lesions

Answer 6

ANS: A
Older children who have an unrepaired septal defect with a left-to-right shunt may become
cyanotic because of pulmonary vascular changes secondary to increased pulmonary blood
flow. None of the other options accurately describe the process that results in cyanosis.

Question 7

Which congenital heart defects occur in trisomy 13, trisomy 18, and Down syndrome?

a. Coarctation of the aorta (COA) and pulmonary stenosis (PS)
b. Tetralogy of Fallot and persistent truncus arteriosus
c. Atrial septal defect (ASD) and dextrocardia
d. Ventricular septal defect (VSD) and patent ductus arteriosus (PDA)

Answer 7

ANS: D
Congenital heart defects that are related to dysfunction of trisomy 13, trisomy 18, and
Down syndrome include VSD and PDA (see Table 33-2). The other defects are not
associated with dysfunction of trisomy 13, trisomy 18, and Down syndrome.

Question 8

An infant has a continuous machine-type murmur best heard at the left upper sternal
border throughout systole and diastole, as well as a bounding pulse and a thrill on
palpation. These clinical findings are consistent with which congenital heart defect?
a. Atrial septal defect (ASD) c. Patent ductus arteriosus (PDA)
b. Ventricular septal defect (VSD) d. Atrioventricular canal (AVC) defect

Answer 8

ANS: C
If pulmonary vascular resistance has fallen, then infants with PDA will characteristically
have a continuous machine-type murmur best heard at the left upper sternal border
throughout systole and diastole. If the PDA is significant, then the infant also will have
bounding pulses, an active precordium, a thrill on palpation, and signs and symptoms of
pulmonary overcirculation. The presentations of the other congenital heart defects are not
consistent with the described the symptoms.

Question 9

An infant has a crescendo-decrescendo systolic ejection murmur located between the
second and third intercostal spaces along the left sternal border. A wide fixed splitting of
the second heart sound is also found. These clinical findings are consistent with which
congenital heart defect?
a. Atrial septal defect (ASD) c. Patent ductus arteriosus (PDA)
b. Ventricular septal defect (VSD) d. Atrioventricular canal (AVC) defect

Answer 9

ANS: A
Because most children with ASD are asymptomatic, diagnosis is usually made during a
routine physical examination by the auscultation of a crescendo-decrescendo systolic
ejection murmur that reflects increased blood flow through the pulmonary valve. The
location of the murmur is between the second and third intercostal spaces along the left
sternal border. A wide fixed splitting of the second heart sound is also characteristic of
ASD, reflecting volume overload to the right ventricle and causing prolonged ejection time
and a delay of pulmonic valve closure. The presentations of other congenital heart defects
are not consistent with the described symptoms.

Question 10

An infant has a loud, harsh, holosystolic murmur and systolic thrill that can be detected at
the left lower sternal border that radiates to the neck. These clinical findings are consistent
with which congenital heart defect?
a. Atrial septal defect (ASD) c. Patent ductus arteriosus (PDA)
b. Ventricular septal defect (VSD) d. Atrioventricular canal (AVC) defect

Answer 10

ANS: B
On physical examination, a loud, harsh, holosystolic murmur and systolic thrill can be
detected at the left lower sternal border. The intensity of the murmur reflects the pressure
gradient across the VSD. An apical diastolic rumble may be present with a
moderate-to-large defect, reflecting increased flow across the mitral valve. The
presentations of the other congenital heart defects are not consistent with the described
symptoms.

Question 11

Where can coarctation of the aorta (COA) be located?
a. Exclusively on the aortic arch
b. Proximal to the brachiocephalic artery
c. Between the origin of the aortic arch and the bifurcation of the aorta in the lower
abdomen
d. Between the origin of the aortic arch and the origin of the first intercostal artery
ANS: C
COA can occur anywhere between the origin of the aortic arch and the bifurcation of the
aorta in the lower abdomen. The other options do not accurately describe the location of a
COA.

Answer 11

ANS: C
COA can occur anywhere between the origin of the aortic arch and the bifurcation of the
aorta in the lower abdomen. The other options do not accurately describe the location of a
COA.

Question 12

Classic manifestations of a systolic ejection murmur heard at the left interscapular area,
cool mottled skin on the lower extremities but hypertension noted in the upper extremities,
and decreased or absent femoral pulse are indicative of an older child with which
congenital defect?
a. Tetralogy of Fallot c. Ventricular septum defect (SD)
b. Aortic stenosis d. Coarctation of the aorta (OA)

Answer 12

ANS: D
Clinical manifestations of coarctation of the aorta include hypertension noted in the upper
extremities with decreased or absent pulses in the lower extremities. Children may also
have cool mottled skin and occasionally experience leg cramps during exercise. A systolic
ejection murmur, heard best at the left interscapular area, is also considered a classic
clinical manifestation of this disorder. The other options are not initially associated with
these symptoms.

Question 13

What is the initial manifestation of aortic coarctation observed in a neonate?

a. Congestive heart failure (CHF) c. Pulmonary hypertension
b. Cor pulmonale d. Cerebral hypertension

Answer 13

ANS: A
Initially, the newborn usually exhibits symptoms of CHF. The other options are not
initially associated with aortic coarctation.

Question 14

Which compensatory mechanism is spontaneously used by children diagnosed with
tetralogy of Fallot to relieve hypoxic spells?
a. Lying on their left side c. Squatting
b. Performing the Valsalva maneuver d. Hyperventilating

Answer 14

ANS: C
Squatting is a spontaneous compensatory mechanism used by older children to alleviate
hypoxic spells. Squatting and its variants increase systemic resistance while decreasing
venous return to the heart from the inferior vena cava. The other options would not result
in these changes.

Question 15

An infant diagnosed with a small patent ductus arteriosus (PDA) would likely exhibit
which symptom?
a. Intermittent murmur c. Need for surgical repair
b. Lack of symptoms d. Triad of congenital defects

Answer 15

ANS: B

Infants with a small PDA usually remain asymptomatic; the other options are incorrect.

Question 16

What is the most common cause of chronic sustained hypertension observed only in a
newborn?
a. Renal parenchymal disease c. Renal artery stenosis
b. Primary hypertension d. Congenital renal malformation

Answer 16

ANS: D
Congenital renal malformation is a cause of chronic sustained hypertension in a newborn.
Although renal artery stenosis is observed in newborns, it is also observed in older
children. Renal parenchymal disease and primary hypertension are commonly observed in
older children diagnosed with chronic sustained hypertension.

Question 17

Which condition is consistent with the cardiac defect of transposition of the great vessels?

a. The aorta arises from the right ventricle.
b. The pulmonary trunk arises from the right ventricle.
c. The right ventricle pumps blood to the lungs.
d. An intermittent murmur is present.

Answer 17

ANS: A
Transposition of the great arteries refers to a condition in which the aorta arises from the
right ventricle and the pulmonary artery arises from the left ventricle. A transposition of
the great vessels is not associated with any of the other options.

Question 18

Which scenario describes total anomalous pulmonary venous return?

a. The foramen ovale closes after birth.
b. Pulmonary venous return is to the right atrium.
c. Pulmonary venous return is to the left atrium.
d. The left atrium receives oxygenated blood.

Answer 18

ANS: B
Total anomalous pulmonary venous return occurs when the pulmonary veins abnormally
connect to the right side of the heart either directly or through one or more systemic veins
that drain into the right atrium. None of the other options accurately describe the
presentation of a total anomalous pulmonary venous return.

Question 19

Which heart defect produces a systolic ejection murmur at the right upper sternal border
that transmits to the neck and left lower sternal border?
a. Coarctation of the aorta c. Aortic stenosis
b. Pulmonic stenosis d. Hypoplastic left heart syndrome

Answer 19

ANS: C
Blood flow through the stenotic area of the aorta produces a systolic ejection murmur at
the right upper sternal border that transmits to the neck and left lower sternal border. None
of the other options produce the described assessment findings.

Question 20

Which heart defect produces a systolic ejection click at the upper left sternal border with a
thrill palpated at the upper left sternal border?
a. Coarctation of the aorta (COA) c. Aortic stenosis
b. Pulmonary stenosis (PS) d. Hypoplastic left heart syndrome

Answer 20

ANS: B
PS results in a systolic ejection murmur at the left upper sternal border, reflecting an
obstruction to flow through the narrowed pulmonary valve. A variable systolic ejection
click is present in some children, as well as valvular stenosis at the upper left sternal
border. PS also produces a thrill that may be palpated at the upper left sternal border. None
of the other options produce the described assessment findings.

Question 21

Which heart defect results in a single vessel arising from both ventricles, providing blood
to both the pulmonary and systemic circulations?
a. Coarctation of the aorta
b. Tetralogy of Fallot
c. Total anomalous pulmonary connection
d. Truncus arteriosus

Answer 21

ANS: D
Truncus arteriosus is the failure of the large embryonic artery, the truncus arteriosus, to
divide into the pulmonary artery and the aorta, which results in a single vessel arising from
both ventricles, providing blood flow to the pulmonary and systemic circulations. None of
the other options produce the described structural malformation.

Question 22

What is the suggested mean blood pressure for an 8- to 9-year-old child?

a. 104/55 mm Hg c. 112/62 mm Hg
b. 106/58 mm Hg d. 121/70 mm Hg

Answer 22

ANS: B
The suggested mean blood pressure for an 8- to 9- year-old child is 106/58 mm Hg. For a
child of 6 to 7 years old, 104/55 mm Hg is appropriate; for a 12- to 13-year-old child,
112/62 mm Hg is appropriate, and for a 16- to 18-year-old young man, 121/70 mm Hg is
appropriate.