An 18-month-old boy presents to the pediatrician by his mother for a routine check-up. The mother has no concerns, although she asks about the "hole in his heart" that the patient had at birth. The patient has no history of cyanosis or heart failure; however, a holosystolic, harsh murmur was noted at the 3- and 6-month check-ups. On examination, the patient is playful and alert. He has met all developmental milestones. The cardiac examination reveals a regular rate and rhythm with persistence of the holosystolic, harsh murmur. What is the most likely cause of the murmur in this child?
Q232
A 28-year-old primigravid woman is brought to the emergency department after complaining of severe abdominal pain for 3 hours. She has had no prenatal care. There is no leakage of amniotic fluid. Since arrival, she has had 5 contractions in 10 minutes, each lasting 70 to 90 seconds. Pelvic examination shows a closed cervix and a uterus consistent in size with a 38-week gestation. Ultrasound shows a single live intrauterine fetus in a breech presentation consistent with a gestational age of approximately 37 weeks. The amniotic fluid index is 26 and the fetal heart rate is 92/min. The placenta is not detached. She is scheduled for an emergency lower segment transverse cesarean section because of a nonreassuring fetal heart rate. The infant is delivered and APGAR score is noted to be 8 at 1 minute. The doctor soon notices cyanosis of the lips and oral mucosa, which does not resolve when the infant cries. The infant is foaming at the mouth and drooling. He also has an intractable cough. Which of the following is the most likely diagnosis?
Q233
Three days after delivery, a 4000-g (8.8-lb) male newborn has several episodes of right-sided arm and leg twitching and lip smacking. These shaking episodes have occurred about six times over the last hour and have lasted for about 40 seconds. He has also had rapid breathing and poor feeding. He has not had fever or trauma. He was born at 37 weeks' gestation. Pregnancy and delivery were uncomplicated. There is no family history of serious illness. His temperature is 37°C (98.6°F), pulse is 230/min, and respirations are 70/min. He appears irritable and jittery. There are intermittent spasms present. The remainder of the examination shows no abnormalities. Laboratory studies show a serum calcium concentration of 6 mg/dL and a serum parathyroid hormone concentration of 150 pg/mL. Which of the following is the most likely underlying cause of this patient's condition?
Q234
A 42-year-old woman presents to the emergency department in active labor. She has had no prenatal care and is unsure of the gestational age. Labor progresses rapidly and spontaneous vaginal delivery of a baby boy occurs 3 hours after presentation. On initial exam, the child is 1.9 kg (4.2 lb) with a small head and jaw. A sac-like structure containing intestine, as can be seen in the picture, protrudes from the abdominal wall. What complication is closely associated with this presentation?
Q235
A 6-year-old boy is brought in for evaluation by his adopted mother due to trouble starting 1st grade. His teacher has reported that he has been having trouble focusing on tasks and has been acting out while in class. His family history is unknown as he was adopted 2 years ago. His temperature is 36.2°C (97.2°F), pulse is 80/min, respirations are 20/min, and blood pressure 110/70 mm Hg. Visual inspection of the boy's face shows a low set nasal bridge, a smooth philtrum, and small lower jaw. Which of the following findings would also likely be found on physical exam?
Q236
A 2-year-old child is brought to the emergency department with rapid breathing and a severe cyanotic appearance of his lips, fingers, and toes. He is known to have occasional episodes of mild cyanosis, especially when he is extremely agitated. This is the worst episode of this child’s life, according to his parents. He was born with an APGAR score of 8 via a normal vaginal delivery. His development is considered delayed compared to children of his age. History is significant for frequent squatting after strenuous activity. On auscultation, there is evidence of a systolic ejection murmur at the left sternal border. On examination, his oxygen saturation is 71%, blood pressure is 81/64 mm Hg, respirations are 42/min, pulse is 129/min, and temperature is 36.7°C (98.0°F). Which of the following will most likely be seen on chest x-ray (CXR)?
Q237
A 2-year-old boy with a history of recurrent respiratory infections is brought to the physician for a follow-up examination. His height and weight are both at the 20th percentile. Crackles are heard in both lower lung fields. Cardiac auscultation shows a grade 3/6 holosystolic murmur over the left lower sternal border and a diastolic rumble heard best at the apex. If left untreated, this patient is most likely to develop which of the following?
Q238
A 3-year-old child is brought to the emergency department by his parents. The child presents with significant rapid breathing and appears unwell. On examination, his liver size is 1.5 times larger than children of his age, and he has mild pitting edema in his legs. This child is also in the lower weight-age and height-age percentiles. On auscultation, mild rales were noted and a fixed split S2 was heard on inspiration. There is no family history of congenital disorders or metabolic syndromes. Which of the following is the likely diagnosis?
Q239
A 7-year-old boy is brought by his parents to his pediatrician due to progressive fatigue and shortness of breath while playing sports. He is otherwise healthy with no known medical disorders and no other symptoms. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. On physical examination, his temperature is 36.9ºC (98.4ºF), pulse rate is 90/min, blood pressure is 100/70 mm Hg, and respiratory rate is 18/min. Pulses in all four extremities are equal and normally palpated; there is no radio-femoral delay. The pediatrician suspects a congenital heart disease after auscultation of the heart. Which of the following congenital heart diseases is most likely to present with the clinical features listed above?
Q240
A 2200-g (4-lbs 13-oz) female newborn is delivered at term to a 37-year-old gravida 2, para 1 woman. The newborn is at the 10th percentile for length, 14th percentile for weight, and 3rd percentile for head circumference. Examination shows “punched-out“ skin lesions on the scalp, cleft lip, and a small chin. There is a convex-shaped deformity of the plantar surface of the feet. Auscultation shows a holosystolic murmur heard best at the left lower sternal border. Some of her intestines protrude through the umbilicus, covered by a thin membranous sac. An MRI of the brain shows a single ventricle and a fusion of the basal ganglia. Which of the following additional findings is most likely to be seen in this patient?
Congenital defects US Medical PG Practice Questions and MCQs
Question 231: An 18-month-old boy presents to the pediatrician by his mother for a routine check-up. The mother has no concerns, although she asks about the "hole in his heart" that the patient had at birth. The patient has no history of cyanosis or heart failure; however, a holosystolic, harsh murmur was noted at the 3- and 6-month check-ups. On examination, the patient is playful and alert. He has met all developmental milestones. The cardiac examination reveals a regular rate and rhythm with persistence of the holosystolic, harsh murmur. What is the most likely cause of the murmur in this child?
A. Patent foramen ovale
B. Defect of muscular interventricular septum
C. Failure of endocardial cushion to form
D. Defect of the membranous interventricular septum (Correct Answer)
E. Defective dynein functioning
Explanation: ***Defect of the membranous interventricular septum***
- A **holosystolic, harsh murmur** is characteristic of a **ventricular septal defect (VSD)**, particularly one in the membranous septum due to its common occurrence and typical presentation.
- The patient's lack of cyanosis or heart failure, despite the persistent murmur since birth, suggests a small to moderate VSD, which can often remain asymptomatic and sometimes close spontaneously.
*Patent foramen ovale*
- A **patent foramen ovale (PFO)** typically produces no murmur or a soft systolic ejection murmur, not a harsh holosystolic murmur.
- PFOs are usually asymptomatic unless there's a significant pressure difference causing a right-to-left shunt, which is not indicated here.
*Failure of endocardial cushion to form*
- Failure of the **endocardial cushions** to form leads to **atrioventricular septal defects (AVSDs)**, which typically present with a combination of murmurs (systolic and sometimes diastolic) and often with symptoms of heart failure and recurrent respiratory infections.
- AVSDs are usually associated with **Down syndrome** and present with more severe clinical features than described.
*Defect of muscular interventricular septum*
- While a **muscular VSD** can cause a holosystolic murmur, it often has a **rougher, "swiss cheese" appearance** on imaging due to multiple defects and is less common than membranous VSDs.
- Small muscular VSDs are more prone to spontaneous closure and may have a different murmur intensity or location.
*Defective dynein functioning*
- **Defective dynein functioning** causes conditions like **Kartagener syndrome** (a type of primary ciliary dyskinesia), characterized by **situs inversus**, chronic sinusitis, bronchiectasis, and infertility.
- This condition does not directly cause an isolated holosystolic heart murmur or structural heart defects like a VSD.
Question 232: A 28-year-old primigravid woman is brought to the emergency department after complaining of severe abdominal pain for 3 hours. She has had no prenatal care. There is no leakage of amniotic fluid. Since arrival, she has had 5 contractions in 10 minutes, each lasting 70 to 90 seconds. Pelvic examination shows a closed cervix and a uterus consistent in size with a 38-week gestation. Ultrasound shows a single live intrauterine fetus in a breech presentation consistent with a gestational age of approximately 37 weeks. The amniotic fluid index is 26 and the fetal heart rate is 92/min. The placenta is not detached. She is scheduled for an emergency lower segment transverse cesarean section because of a nonreassuring fetal heart rate. The infant is delivered and APGAR score is noted to be 8 at 1 minute. The doctor soon notices cyanosis of the lips and oral mucosa, which does not resolve when the infant cries. The infant is foaming at the mouth and drooling. He also has an intractable cough. Which of the following is the most likely diagnosis?
A. Pulmonary hypoplasia
B. Defective swallowing reflex
C. Esophageal stricture
D. Achalasia
E. Esophageal atresia (Correct Answer)
Explanation: ***Esophageal atresia***
- The triad of **cyanosis**, **foaming at the mouth** (due to inability to swallow saliva), and **intractable coughing** strongly suggests esophageal atresia, especially given the history of polyhydramnios (amniotic fluid index of 26) which often accompanies this condition.
- The inability of the newborn to clear secretions due to the blind-ending esophagus leads to aspiration and respiratory distress.
*Pulmonary hypoplasia*
- This condition is characterized by underdeveloped lungs and would present with severe respiratory distress, but typically without the prominent signs of **excessive oral secretions** and **foaming at the mouth**.
- Pulmonary hypoplasia is often associated with conditions causing oligohydramnios (e.g., renal agenesis), whereas this case presents with polyhydramnios.
*Defective swallowing reflex*
- While a defective swallowing reflex could lead to aspiration, it usually wouldn't cause the rapid accumulation of **foaming at the mouth** and intractable coughing to the degree seen with a complete esophageal obstruction.
- This is a more generalized neurological issue, whereas esophageal atresia is a structural malformation.
*Esophageal stricture*
- An esophageal stricture would cause difficulty swallowing (dysphagia), but typically allows some passage of liquids and wouldn't present with immediate, complete inability to swallow saliva and copious **foaming at the mouth** from birth.
- Strictures are more commonly acquired (e.g., from reflux or injury) rather than presenting congenitally with such acute and severe symptoms.
*Achalasia*
- Achalasia is a motility disorder of the esophagus characterized by impaired relaxation of the lower esophageal sphincter and absence of peristalsis; it is extremely rare in neonates.
- Symptoms like **dysphagia** and **regurgitation** typically develop gradually and are less likely to cause the acute, severe respiratory distress and foaming at the mouth seen immediately after birth in this case.
Question 233: Three days after delivery, a 4000-g (8.8-lb) male newborn has several episodes of right-sided arm and leg twitching and lip smacking. These shaking episodes have occurred about six times over the last hour and have lasted for about 40 seconds. He has also had rapid breathing and poor feeding. He has not had fever or trauma. He was born at 37 weeks' gestation. Pregnancy and delivery were uncomplicated. There is no family history of serious illness. His temperature is 37°C (98.6°F), pulse is 230/min, and respirations are 70/min. He appears irritable and jittery. There are intermittent spasms present. The remainder of the examination shows no abnormalities. Laboratory studies show a serum calcium concentration of 6 mg/dL and a serum parathyroid hormone concentration of 150 pg/mL. Which of the following is the most likely underlying cause of this patient's condition?
A. Neonatal ingestion of formula with high phosphate load (Correct Answer)
B. Neonatal hypoglycemia
C. Increased neonatal thyroid hormone secretion
D. Maternal opioid abuse during pregnancy
E. Maternal familial hypocalciuric hypercalcemia
Explanation: ***Neonatal ingestion of formula with high phosphate load***
- The newborn's symptoms, including **twitching, lip smacking, rapid breathing, poor feeding, irritability, jitteriness**, and intermittent spasms, are classic signs of **neonatal hypocalcemia with seizures**.
- The lab results confirm **hypocalcemia (serum calcium 6 mg/dL)** with **elevated parathyroid hormone (PTH 150 pg/mL)**, indicating **secondary hyperparathyroidism** caused by high phosphate intake.
- High-phosphate formulas (especially cow's milk-based formulas) can cause hyperphosphatemia, which binds calcium and stimulates PTH release, leading to this clinical picture.
- The **tachycardia (pulse 230/min)** can occur as a compensatory response to metabolic stress and seizure activity in neonates with severe hypocalcemia.
*Neonatal hypoglycemia*
- While hypoglycemia can cause seizures and irritability, it typically presents with **blood glucose <40 mg/dL** and would not explain the specific calcium and PTH abnormalities seen.
- The laboratory findings clearly point to a calcium-related disorder, not glucose dysregulation.
*Increased neonatal thyroid hormone secretion*
- **Neonatal hyperthyroidism** can present with **tachycardia, irritability, poor weight gain, and tremors**, which might seem to fit this case.
- However, neonatal thyrotoxicosis typically causes **hypercalcemia** (from increased bone turnover), not hypocalcemia, making this an unlikely diagnosis.
- Additionally, hyperthyroidism would not explain the markedly elevated PTH seen in this patient.
*Maternal opioid abuse during pregnancy*
- **Neonatal abstinence syndrome (NAS)** from maternal opioid abuse causes irritability, tremors, and poor feeding but typically includes specific signs like **nasal stuffiness, sneezing, yawning, high-pitched cry, and diarrhea**.
- NAS would not directly lead to hypocalcemia with elevated PTH, and there is no mention of maternal substance use history.
*Maternal familial hypocalciuric hypercalcemia*
- When a mother has **familial hypocalciuric hypercalcemia (FHH)**, she has mild chronic hypercalcemia.
- The fetus is exposed to elevated maternal calcium in utero, which **suppresses fetal parathyroid gland development**.
- After birth, this results in **neonatal hypocalcemia with LOW or inappropriately normal PTH** (transient hypoparathyroidism), not the elevated PTH seen in this patient.
- The markedly elevated PTH (150 pg/mL) effectively rules out this diagnosis.
Question 234: A 42-year-old woman presents to the emergency department in active labor. She has had no prenatal care and is unsure of the gestational age. Labor progresses rapidly and spontaneous vaginal delivery of a baby boy occurs 3 hours after presentation. On initial exam, the child is 1.9 kg (4.2 lb) with a small head and jaw. A sac-like structure containing intestine, as can be seen in the picture, protrudes from the abdominal wall. What complication is closely associated with this presentation?
A. Lack of abdominal wall muscles
B. Dehydration and necrosis of bowel
C. Duodenal atresia
D. Twisting of the bowel around itself
E. Cardiac defect (Correct Answer)
Explanation: ***Cardiac defect***
- The presentation of a **sac-like structure containing intestine protruding from the abdominal wall** (suggesting an **omphalocele**) along with **microcephaly** (small head), **micrognathia** (small jaw), and **low birth weight** are classic features of **Patau syndrome (Trisomy 13)** or **Edwards syndrome (Trisomy 18)**.
- These chromosomal abnormalities are strongly associated with various significant anomalies, including severe **cardiac defects** (e.g., ventricular septal defects, patent ductus arteriosus, atrial septal defects), which occur in **>80% of cases**.
- **Omphalocele** itself is associated with cardiac anomalies in approximately **30-50% of cases**, making cardiac defects the most closely associated complication.
*Lack of abdominal wall muscles*
- This description is more indicative of **prune belly syndrome (Eagle-Barrett syndrome)**, characterized by absence or deficiency of abdominal wall musculature.
- With **gastroschisis**, there is also an abdominal wall defect, but the defect is typically lateral to the umbilicus and there is no protective sac covering the bowel.
*Dehydration and necrosis of bowel*
- This complication is more characteristic of **gastroschisis** due to the direct exposure of the unprotected bowel to amniotic fluid, leading to inflammation, thickening, and potential vascular compromise.
- In an **omphalocele**, the bowel is protected by a sac (containing peritoneum and amnion), significantly reducing the immediate risk of dehydration and necrosis unless the sac ruptures.
*Duodenal atresia*
- **Duodenal atresia** is strongly associated with **Down syndrome (Trisomy 21)**, characterized by a "double bubble" sign on imaging.
- While omphalocele can occasionally occur with Trisomy 21, the constellation of findings in this case (microcephaly, micrognathia, low birth weight) is more consistent with Trisomy 13 or 18 rather than Trisomy 21.
*Twisting of the bowel around itself*
- **Volvulus** refers to the twisting of a loop of intestine around its mesentery, which can lead to bowel obstruction and ischemia.
- While volvulus can occur with intestinal malrotation (which may be present with omphalocele), it is not the most closely associated **congenital** complication of the chromosomal syndrome suggested by this clinical presentation.
Question 235: A 6-year-old boy is brought in for evaluation by his adopted mother due to trouble starting 1st grade. His teacher has reported that he has been having trouble focusing on tasks and has been acting out while in class. His family history is unknown as he was adopted 2 years ago. His temperature is 36.2°C (97.2°F), pulse is 80/min, respirations are 20/min, and blood pressure 110/70 mm Hg. Visual inspection of the boy's face shows a low set nasal bridge, a smooth philtrum, and small lower jaw. Which of the following findings would also likely be found on physical exam?
A. Cataracts
B. Congenital deafness
C. Holosystolic murmur (Correct Answer)
D. Limb hypoplasia
E. Wide notched teeth
Explanation: **Holosystolic murmur**
- The child exhibits classic features of **fetal alcohol syndrome** (FAS), including the distinctive facial anomalies (low set nasal bridge, smooth philtrum, small lower jaw) and developmental/behavioral issues (trouble focusing, acting out).
- Up to 50% of children with FAS develop **congenital heart defects**, with **ventricular septal defects (VSDs)** being the most common, which are characterized by a **holosystolic murmur** at the lower left sternal border.
*Cataracts*
- **Cataracts** are not a typical feature of fetal alcohol syndrome but are often associated with congenital infections such as **rubella** or **cytomegalovirus**.
- While some genetic syndromes can include cataracts, they are not a primary finding for the constellation of symptoms observed here.
*Congenital deafness*
- **Congenital deafness** is not a hallmark of fetal alcohol syndrome; rather, it is commonly associated with congenital infections like **rubella**, **CMV**, or genetic syndromes such as **CHARGE syndrome**.
- Children with FAS may have hearing problems due to recurrent ear infections, but not typically congenital deafness.
*Limb hypoplasia*
- **Limb hypoplasia** is typically seen in conditions like **thalidomide embryopathy** or certain genetic syndromes, such as **Roberts syndrome**.
- While growth restriction is common in FAS, significant limb hypoplasia as described is not a characteristic feature.
*Wide notched teeth*
- **Wide notched teeth**, also known as **Hutchinson teeth**, are pathognomonic for **congenital syphilis**.
- This finding is unrelated to fetal alcohol syndrome, and the patient's other symptoms do not suggest congenital syphilis.
Question 236: A 2-year-old child is brought to the emergency department with rapid breathing and a severe cyanotic appearance of his lips, fingers, and toes. He is known to have occasional episodes of mild cyanosis, especially when he is extremely agitated. This is the worst episode of this child’s life, according to his parents. He was born with an APGAR score of 8 via a normal vaginal delivery. His development is considered delayed compared to children of his age. History is significant for frequent squatting after strenuous activity. On auscultation, there is evidence of a systolic ejection murmur at the left sternal border. On examination, his oxygen saturation is 71%, blood pressure is 81/64 mm Hg, respirations are 42/min, pulse is 129/min, and temperature is 36.7°C (98.0°F). Which of the following will most likely be seen on chest x-ray (CXR)?
A. Egg on a string
B. Boot-shaped heart (Correct Answer)
C. Increased pulmonary vascular markings
D. Cardiomegaly with globular heart
E. Figure-3 sign
Explanation: ***Boot-shaped heart***
- The patient's presentation with **cyanosis**, **squatting spells**, and a **systolic ejection murmur** is classic for **Tetralogy of Fallot** (TOF).
- A **boot-shaped heart** (Coeur en sabot) on chest X-ray is a characteristic finding in TOF, caused by **right ventricular hypertrophy** and an upturned cardiac apex, leading to a concave pulmonary artery segment.
*Egg on a string*
- This CXR finding is characteristic of **Transposition of the Great Arteries (TGA)**, where the aorta and pulmonary artery are switched, creating an "egg" outline with a narrow vascular pedicle ("string").
- TGA typically presents with severe **cyanosis** from birth and does not usually involve squatting spells or a loud systolic murmur from a prominent **right ventricular outflow tract obstruction**.
*Increased pulmonary vascular markings*
- This finding is common in conditions with **left-to-right shunting** or **increased pulmonary blood flow**, such as a **ventricular septal defect (VSD)** or **patent ductus arteriosus (PDA)**.
- In Tetralogy of Fallot, there is typically **decreased pulmonary blood flow** due to **pulmonic stenosis**, leading to *decreased* pulmonary vascular markings.
*Cardiomegaly with globular heart*
- A **globular heart** is a non-specific finding often associated with **pericardial effusion** or **dilated cardiomyopathy**, where the heart appears enlarged and rounded.
- While TOF can cause cardiomegaly (specifically **right ventricular hypertrophy**), the characteristic shape is "boot-shaped," not globally enlarged or globular.
*Figure-3 sign*
- The **figure-3 sign** on CXR is pathognomonic for **aortic coarctation**, caused by indentation of the aorta at the coarctation site and post-stenotic dilation.
- This condition presents with signs of **heart failure**, **differential cyanosis** (if preductal), and **blood pressure discrepancies** between upper and lower extremities, not the cyanotic spells and squatting seen in this case.
Question 237: A 2-year-old boy with a history of recurrent respiratory infections is brought to the physician for a follow-up examination. His height and weight are both at the 20th percentile. Crackles are heard in both lower lung fields. Cardiac auscultation shows a grade 3/6 holosystolic murmur over the left lower sternal border and a diastolic rumble heard best at the apex. If left untreated, this patient is most likely to develop which of the following?
A. Digital clubbing (Correct Answer)
B. Thrombocytosis
C. Secondary hypertension
D. Aortic dissection
E. Chronic kidney disease
Explanation: ***Digital clubbing***
- The presence of a **holosystolic murmur** at the left lower sternal border and a **diastolic rumble** at the apex, along with recurrent respiratory infections and poor growth, strongly suggests a significant **ventricular septal defect (VSD)** with subsequent pulmonary hypertension and eventual Eisenmenger syndrome.
- **Clubbing** is a common manifestation of chronic hypoxemia, which occurs as shunt reversal develops in Eisenmenger syndrome due to severe pulmonary hypertension.
*Thrombocytosis*
- While some congenital heart defects can be associated with hematological changes, **thrombocytosis** is not a characteristic long-term complication of untreated VSD or Eisenmenger syndrome.
- Instead, **polycythemia** (increased red blood cell count) is more likely due to chronic hypoxemia.
*Secondary hypertension*
- **Pulmonary hypertension** is a direct complication of a large, untreated VSD, but systemic **secondary hypertension** is not a typical consequence of this condition.
- The primary issue is increased pressure in the pulmonary circulation, not systemic blood pressure dysregulation.
*Aortic dissection*
- **Aortic dissection** is primarily associated with conditions like uncontrolled **systemic hypertension**, Marfan syndrome, or Ehlers-Danlos syndrome.
- It is not a direct or likely complication of an untreated large VSD or the resulting pulmonary hypertension.
*Chronic kidney disease*
- While long-standing cyanotic heart disease can sometimes lead to organ dysfunction, **chronic kidney disease** is not a primary or direct long-term complication of an untreated VSD or Eisenmenger syndrome.
- Kidney issues in cardiac disease are typically related to severe heart failure or specific syndromes like cardiorenal syndrome, which are not the most prominent features here.
Question 238: A 3-year-old child is brought to the emergency department by his parents. The child presents with significant rapid breathing and appears unwell. On examination, his liver size is 1.5 times larger than children of his age, and he has mild pitting edema in his legs. This child is also in the lower weight-age and height-age percentiles. On auscultation, mild rales were noted and a fixed split S2 was heard on inspiration. There is no family history of congenital disorders or metabolic syndromes. Which of the following is the likely diagnosis?
A. Liver failure
B. Atrial septal defect (Correct Answer)
C. Endocardial cushion syndrome
D. Transposition of the great vessels
E. Patent foramen ovale
Explanation: ***Atrial septal defect***
- A **fixed split S2** is a hallmark physical finding, caused by delayed pulmonic valve closure due to increased right ventricular volume.
- The symptoms of **rapid breathing**, **hepatomegaly**, **edema**, and **failure to thrive** are consistent with chronic volume overload on the right side of the heart, leading to pulmonary hypertension and eventual right-sided heart failure.
*Liver failure*
- While **hepatomegaly** and **edema** can occur in liver failure, the accompanying **fixed split S2** points primarily to a cardiac etiology.
- Absence of jaundice, coagulopathy, or significant encephalopathy makes primary liver failure less likely.
*Endocardial cushion syndrome*
- This condition involves defects in the **atrial septum**, **ventricular septum**, and **AV valves**, leading to more severe and earlier onset heart failure symptoms, often with a different murmur profile.
- It would typically present with a **loud systolic murmur** due to mitral or tricuspid regurgitation, or a Holosystolic murmur due to a VSD, which is not mentioned here.
*Transposition of the great vessels*
- This is a **cyanotic heart defect** presenting with profound cyanosis shortly after birth, which is not described in this 3-year-old child.
- The clinical presentation with a **fixed split S2** and signs of chronic heart failure is not typical for an uncorrected transposition.
*Patent foramen ovale*
- A **patent foramen ovale (PFO)** is typically asymptomatic and usually doesn't cause significant shunting or symptoms like heart failure unless there are conditions leading to right-to-left shunting.
- It does not typically present with a **fixed split S2** or the other widespread signs of chronic cardiac compromise seen in this patient.
Question 239: A 7-year-old boy is brought by his parents to his pediatrician due to progressive fatigue and shortness of breath while playing sports. He is otherwise healthy with no known medical disorders and no other symptoms. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. On physical examination, his temperature is 36.9ºC (98.4ºF), pulse rate is 90/min, blood pressure is 100/70 mm Hg, and respiratory rate is 18/min. Pulses in all four extremities are equal and normally palpated; there is no radio-femoral delay. The pediatrician suspects a congenital heart disease after auscultation of the heart. Which of the following congenital heart diseases is most likely to present with the clinical features listed above?
A. Atrial septal defect (Correct Answer)
B. Double-outlet right ventricle with subaortic ventricular septal defect
C. Coarctation of the aorta
D. Aortopulmonary window defect
E. Complete atrioventricular septal defect
Explanation: ***Atrial septal defect***
- An **atrial septal defect (ASD)** typically presents in older children or adults with symptoms like **fatigue** and **shortness of breath on exertion (dyspnea)** due to increased pulmonary blood flow, after years of being asymptomatic.
- The absence of cyanosis and normal pulses are consistent with an ASD, as it's typically an **acyanotic heart defect** where shunting occurs from left to right.
*Double-outlet right ventricle with subaortic ventricular septal defect*
- This condition involves both great arteries originating from the **right ventricle**, often leading to **cyanosis** from birth or early infancy due to mixing of oxygenated and deoxygenated blood.
- Patients typically present much earlier with signs of **heart failure**, **cyanosis**, and **failure to thrive**, which are not reported in this 7-year-old boy.
*Coarctation of the aorta*
- **Coarctation of the aorta** is characterized by a **narrowing of the aorta**, leading to a classic finding of **radio-femoral delay** and **different blood pressures in the upper and lower extremities**, which are specifically stated to be absent in this patient.
- While it can cause shortness of breath and fatigue, the lack of radio-femoral delay makes this diagnosis unlikely.
*Aortopulmonary window defect*
- An **aortopulmonary window (APW)** is a rare defect involving a communication between the aorta and pulmonary artery, usually presenting in **infancy** with severe symptoms of **heart failure** and **pulmonary hypertension** due to a large left-to-right shunt.
- This patient's presentation at 7 years of age without early severe symptoms makes APW less likely.
*Complete atrioventricular septal defect*
- A **complete atrioventricular septal defect (AVSD)** involves a defect in both the atrial and ventricular septa and a common AV valve, usually causing **severe symptoms of heart failure** and **pulmonary hypertension in infancy**.
- It is also strongly associated with **Down syndrome**, which is not mentioned, and severe symptoms would have presented much earlier than age 7.
Question 240: A 2200-g (4-lbs 13-oz) female newborn is delivered at term to a 37-year-old gravida 2, para 1 woman. The newborn is at the 10th percentile for length, 14th percentile for weight, and 3rd percentile for head circumference. Examination shows “punched-out“ skin lesions on the scalp, cleft lip, and a small chin. There is a convex-shaped deformity of the plantar surface of the feet. Auscultation shows a holosystolic murmur heard best at the left lower sternal border. Some of her intestines protrude through the umbilicus, covered by a thin membranous sac. An MRI of the brain shows a single ventricle and a fusion of the basal ganglia. Which of the following additional findings is most likely to be seen in this patient?
A. Polydactyly (Correct Answer)
B. Single palmar crease
C. Hypoplastic philtrum
D. Overlapping fingers
E. Webbed neck
Explanation: ***Polydactyly***
- The constellation of findings, including **growth restriction**, **cleft lip**, **holosystolic murmur** (suggesting a VSD), **omphalocele**, **microcephaly** (3rd percentile), and severe brain abnormalities like a **single ventricle** and **fused basal ganglia**, is highly indicative of **trisomy 13 (Patau syndrome)**.
- **Polydactyly** (extra fingers or toes) is a very common and characteristic skeletal anomaly seen in infants with trisomy 13.
*Single palmar crease*
- A **single palmar crease** (simian crease) is a common finding in **Down syndrome (Trisomy 21)**, which presents with a different phenotype.
- While it can occasionally be seen in other conditions, it is not a primary or characteristic feature of Patau syndrome.
*Hypoplastic philtrum*
- A **hypoplastic philtrum** (thin upper lip and smooth philtrum) is a hallmark feature of **fetal alcohol syndrome**.
- This patient's presentation does not align with the typical features of fetal alcohol syndrome.
*Overlapping fingers*
- **Overlapping fingers** (camptodactyly or syndactyly with overlapping) are a characteristic feature of **Edwards syndrome (Trisomy 18)**.
- Edwards syndrome has distinct features like rocker-bottom feet, prominent occiput, and micrognathia, which differ from this patient's findings.
*Webbed neck*
- A **webbed neck** is a classic phenotypic feature associated with **Turner syndrome (XO)** and sometimes seen in Noonan syndrome.
- This patient's findings, particularly the severe brain malformations and omphalocele, are not characteristic of Turner syndrome.
