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ABTS Congenital Cardiac study materials
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ABTS Congenital Cardiac practice questions

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Question 1Neonatal and Infant Congenital Cardiac Surgery

A neonate with pulmonary atresia and an intact ventricular septum has ductal-dependent pulmonary blood flow and is awaiting catheter intervention. Which infusion is most appropriate to maintain ductal patency?

  1. Milrinone infusion
  2. Alprostadil infusion Correct answer.
  3. Oral propranolol
  4. Furosemide by slow intravenous bolus

Explanation

Alprostadil (prostaglandin E1) relaxes ductal smooth muscle and keeps the ductus arteriosus open, preserving pulmonary blood flow until catheter or surgical intervention can be planned. Diuretics, inodilators and beta-blockers have no duct-opening effect.

Question 2Neonatal and Infant Congenital Cardiac Surgery

In a neonate with d-transposition of the great arteries and an intact ventricular septum, when should the arterial switch operation ideally be performed?

  1. Electively once the child is older than 1 year of age
  2. Immediately after 6 months of age
  3. After the infant reaches 10 kg
  4. Within the first 1 to 2 weeks of life Correct answer.

Explanation

The arterial switch is best performed within the first 1–2 weeks of life, while the left ventricle is still conditioned to systemic pressure. Beyond about 3–4 weeks in a patient with an intact ventricular septum, left ventricular mass regresses and retraining may be required.

Question 3Neonatal and Infant Congenital Cardiac Surgery

A 4-month-old with tetralogy of Fallot becomes deeply cyanosed and agitated during a crying episode. Which is the most appropriate initial intervention?

  1. Intravenous furosemide
  2. Urgent cardiac catheterization with balloon valvuloplasty
  3. Knee-chest position with supplemental oxygen Correct answer.
  4. Oral propranolol maintenance

Explanation

Knee-chest positioning raises systemic vascular resistance and reduces the right-to-left shunt, while supplemental oxygen lowers pulmonary vascular resistance. Morphine, fluid boluses and phenylephrine are added if the spell persists.

Question 4Neonatal and Infant Congenital Cardiac Surgery

Which clinical finding is most characteristic of coarctation of the aorta in a neonate?

  1. Cyanosis confined to the lower limbs
  2. Diminished femoral pulses with upper-limb hypertension Correct answer.
  3. Bounding femoral pulses with a wide pulse pressure
  4. A continuous machinery murmur at the left infraclavicular area

Explanation

Coarctation produces a systolic pressure gradient between the upper and lower body, so upper-limb blood pressure is elevated while femoral pulses are weak and delayed. Differential cyanosis points instead to a ductal right-to-left shunt.

Question 5Neonatal and Infant Congenital Cardiac Surgery

Which cardiac lesion is most strongly associated with trisomy 21 in infancy?

  1. d-Transposition of the great arteries
  2. Tricuspid atresia
  3. Complete atrioventricular septal defect Correct answer.
  4. Anomalous origin of the left coronary artery from the pulmonary artery

Explanation

Complete atrioventricular septal defect is the lesion most characteristic of trisomy 21 and occurs in a large proportion of infants with Down syndrome who have congenital heart disease. Transposition is linked to maternal diabetes, and anomalous coronary origin has no such association.

Question 6Neonatal and Infant Congenital Cardiac Surgery

At what age is a bidirectional cavopulmonary (Glenn) anastomosis typically performed in an infant with single-ventricle physiology?

  1. At 3 to 6 months of age Correct answer.
  2. At 2 to 3 years of age
  3. Only after Fontan completion
  4. During the first week of life

Explanation

The bidirectional Glenn is usually performed at 3–6 months, once pulmonary vascular resistance has fallen and the infant is being weaned from neonatal shunt physiology. Fontan completion typically follows at 2–4 years.

Question 7Neonatal and Infant Congenital Cardiac Surgery

Which medication is used for pharmacological closure of a haemodynamically significant patent ductus arteriosus in a preterm infant?

  1. Alprostadil
  2. Ibuprofen Correct answer.
  3. Sildenafil
  4. Dexmedetomidine

Explanation

Cyclo-oxygenase inhibitors such as ibuprofen, indomethacin and paracetamol reduce prostaglandin synthesis and promote constriction of a haemodynamically significant ductus in preterm infants. Alprostadil does the opposite.

Question 8Neonatal and Infant Congenital Cardiac Surgery

A neonate with isolated congenital complete heart block has a ventricular rate of 50 beats per minute and a narrow escape rhythm. Which management is most appropriate?

  1. Isoproterenol infusion as definitive long-term therapy
  2. Radiofrequency ablation of the atrioventricular node
  3. Permanent epicardial pacemaker implantation Correct answer.
  4. Observation alone until 1 year of age

Explanation

Congenital complete atrioventricular block with a slow ventricular rate, symptoms or ventricular dysfunction is an indication for permanent pacing, and epicardial leads are preferred in small infants. Isoproterenol is only a temporising measure.

Question 9Neonatal and Infant Congenital Cardiac Surgery

After a Norwood operation with a modified Blalock–Taussig–Thomas shunt, a neonate has an arterial oxygen saturation of 82%, a mixed venous saturation of 42% and a rising lactate; echocardiography shows a large shunt with pulmonary overcirculation. Which step is most likely to improve systemic oxygen delivery?

  1. Enlarging the shunt by catheter intervention
  2. Transfusing packed red cells to a haematocrit of 60%
  3. Reducing pulmonary blood flow while supporting systemic cardiac output Correct answer.
  4. Increasing the inspired oxygen to 100% and hyperventilating the neonate

Explanation

Systemic oxygen delivery depends on cardiac output and arterial oxygen content; when the shunt is too large, pulmonary overcirculation steals systemic flow and the mixed venous saturation falls despite an acceptable arterial saturation. The aim is a balanced circulation with arterial saturation around 75–85%, achieved by limiting pulmonary blood flow and supporting ventricular function.

Question 10Neonatal and Infant Congenital Cardiac Surgery

A 3-day-old with obstructed supracardiac total anomalous pulmonary venous connection is ventilated and profoundly cyanosed. What is the most appropriate management?

  1. Balloon atrial septostomy as definitive treatment
  2. Urgent surgical repair after stabilization Correct answer.
  3. Elective repair at 6 months of age
  4. Prostaglandin E1 infusion to maintain ductal patency

Explanation

Obstructed total anomalous pulmonary venous connection is a surgical emergency, because pulmonary venous hypertension rapidly causes pulmonary oedema, hypoxaemia and death. Stabilization is brief and definitive repair should not be delayed.

Question 11Neonatal and Infant Congenital Cardiac Surgery

Which statement best describes the standard complete repair of truncus arteriosus in infancy?

  1. Ligation of the truncal valve and placement of a systemic-to-pulmonary shunt
  2. VSD closure with a right ventricle-to-pulmonary artery conduit Correct answer.
  3. Anatomic repair using the native main pulmonary artery without any conduit
  4. Banding of both pulmonary arteries with later conduit placement

Explanation

Complete repair consists of closing the ventricular septal defect, detaching the pulmonary arteries from the truncal root, and restoring right ventricle-to-pulmonary artery continuity with a conduit. The truncal valve is often dysplastic and may require repair at the same operation.

Question 12Neonatal and Infant Congenital Cardiac Surgery

A neonate with a type B interrupted aortic arch and a ventricular septal defect becomes jittery and has a prolonged QT interval. Which electrolyte abnormality should be suspected?

  1. Hypocalcaemia Correct answer.
  2. Hyperkalaemia
  3. Hypernatraemia
  4. Hypoglycaemia

Explanation

Type B interrupted aortic arch is strongly associated with 22q11.2 deletion syndrome, in which hypoparathyroidism causes hypocalcaemia that may present with jitteriness, seizures or arrhythmia. Ionised calcium should be measured and replaced.

Question 13Neonatal and Infant Congenital Cardiac Surgery

A 5-day-old presents in shock with weak pulses and a 70 mmHg gradient across the aortic valve; the left ventricle is poorly contracting and the ductus is closing. Which initial step is most appropriate?

  1. Give intravenous furosemide and observe closely
  2. Perform immediate surgical aortic valve replacement
  3. Start prostaglandin E1 while arranging balloon aortic valvotomy Correct answer.
  4. Start high-dose epinephrine to increase contractility

Explanation

Prostaglandin E1 reopens the ductus and restores systemic perfusion while balloon aortic valvotomy is arranged. High-dose inotropes raise afterload and myocardial oxygen demand in an obstructed left ventricle and can precipitate deterioration.

Question 14Neonatal and Infant Congenital Cardiac Surgery

A 3-kg neonate with pulmonary atresia requires a modified Blalock–Taussig–Thomas shunt. Which shunt diameter is most appropriate?

  1. 5.0 mm
  2. 2.0 mm
  3. 3.5 mm Correct answer.
  4. 6.0 mm

Explanation

A modified Blalock–Taussig–Thomas shunt of about 3.0–3.5 mm is appropriate for a 3-kg neonate. Oversizing causes pulmonary overcirculation and heart failure, while undersizing produces persistent hypoxaemia and shunt thrombosis.

Question 15Neonatal and Infant Congenital Cardiac Surgery

What is the principal purpose of fenestrating an extracardiac Fontan conduit?

  1. To maintain systemic ventricular preload at the cost of mild cyanosis Correct answer.
  2. To reduce the risk of conduit thrombosis
  3. To allow future catheter access to the pulmonary arteries
  4. To decrease pulmonary artery pressure by increasing pulmonary blood flow

Explanation

A fenestration allows a controlled right-to-left shunt that maintains ventricular preload and cardiac output while pulmonary vascular resistance is labile, at the price of mild hypoxaemia. It often closes spontaneously or can be closed percutaneously later.

Question 16Neonatal and Infant Congenital Cardiac Surgery

Which operation restores the morphological left ventricle to the systemic circulation in congenitally corrected transposition of the great arteries?

  1. Fontan completion
  2. Double switch operation Correct answer.
  3. Arterial switch operation alone
  4. Classic Senning procedure alone

Explanation

The double switch combines an atrial baffle with an arterial switch so that the morphological left ventricle becomes the systemic pump. In some patients a pulmonary artery band is needed first to train the left ventricle.

Question 17Neonatal and Infant Congenital Cardiac Surgery

A neonate with Ebstein anomaly is deeply cyanosed; echocardiography shows a massively enlarged right atrium and severe tricuspid regurgitation. Which mechanism best explains the cyanosis?

  1. Intrapulmonary arteriovenous malformations
  2. Severe pulmonary valve stenosis
  3. Right-to-left shunting across a stretched atrial septum Correct answer.
  4. Left ventricular failure with pulmonary oedema

Explanation

Severe tricuspid regurgitation raises right atrial pressure above left atrial pressure, so blood shunts right-to-left through the foramen ovale and causes cyanosis; effective pulmonary blood flow also falls. Management may require ductal patency and, in severe cases, a systemic-to-pulmonary shunt.

Question 18Neonatal and Infant Congenital Cardiac Surgery

During cardiopulmonary bypass in a neonate, which test is most commonly used to titrate heparin and protamine dosing?

  1. Platelet function assay
  2. Activated clotting time Correct answer.
  3. Bleeding time
  4. D-dimer

Explanation

The activated clotting time is the standard point-of-care test used to titrate heparin and protamine during paediatric cardiopulmonary bypass, usually targeting values above 400–480 seconds. Neonates have low antithrombin and a large circuit prime relative to blood volume.

Question 19Neonatal and Infant Congenital Cardiac Surgery

A 3-month-old with a large perimembranous ventricular septal defect has poor feeding, tachypnoea and failure to thrive despite diuretic therapy, with normal pulmonary vascular resistance. What is the most appropriate recommendation?

  1. Continue medical therapy until 2 years of age
  2. Pulmonary artery banding with delayed closure
  3. Surgical closure during the current admission Correct answer.
  4. Percutaneous device closure at 6 months of age

Explanation

A large ventricular septal defect with failure to thrive, tachypnoea and poor feeding despite diuretic therapy is an indication for surgical closure during infancy. Delay exposes the child to progressive pulmonary vascular disease and persistent growth failure.

Question 20Neonatal and Infant Congenital Cardiac Surgery

A 2-week-old has refractory hypotension and hypoxaemia (lactate 12 mmol/L) after an arterial switch operation; tamponade and residual lesions have been excluded and maximal inotropic and pulmonary vasodilator therapy is in place. Which next step is most appropriate?

  1. Initiate venoarterial extracorporeal membrane oxygenation Correct answer.
  2. Increase inhaled nitric oxide to 80 ppm
  3. Escalate vasoactive support with a second inotrope
  4. Begin systemic anticoagulation for presumed thrombosis

Explanation

Venoarterial extracorporeal membrane oxygenation is indicated when cardiopulmonary failure persists after full resuscitation, once residual lesions and tamponade have been excluded. Further escalation of inotropes or pulmonary vasodilators in this setting raises myocardial oxygen demand without improving outcome.

Question 21Neonatal and Infant Congenital Cardiac Surgery

A neonate with pulmonary atresia and an intact ventricular septum has right ventricular-to-coronary fistulas with aortic-to-coronary flow that depends on right ventricular pressure. What is the principal hazard of decompressing the right ventricle?

  1. Pulmonary venous obstruction from left atrial hypertension
  2. Lowering RV pressure may cause coronary ischemia Correct answer.
  3. Coronary sinus rupture during venous cannulation
  4. Systemic air embolism through the fistula

Explanation

When coronary perfusion depends on suprasystemic right ventricular pressure through ventriculo-coronary fistulas, decompressing the right ventricle lowers the driving pressure and can cause ischaemic collapse. These patients are often managed with a systemic-to-pulmonary shunt without right ventricular decompression, followed by single-ventricle palliation.

Question 22Neonatal and Infant Congenital Cardiac Surgery

A 2-month-old with poor feeding and sweating has cardiomegaly, mitral regurgitation and depressed left ventricular function; the left coronary artery arises from the pulmonary artery. Which mechanism best explains the ischaemia?

  1. Global myocardial ischemia from severe anemia
  2. Coronary steal into the low-pressure pulmonary artery Correct answer.
  3. Aortic root dilation compressing the left main coronary artery
  4. Coronary ostial stenosis from a dysplastic aortic valve

Explanation

After pulmonary vascular resistance falls, flow in the anomalous left coronary artery reverses into the pulmonary artery, producing a coronary steal and subendocardial ischaemia. Surgical reimplantation or reconstruction restores a two-coronary circulation.

Question 23Neonatal and Infant Congenital Cardiac Surgery

Which combination of procedures constitutes the hybrid stage 1 palliation for hypoplastic left heart syndrome?

  1. Norwood arch reconstruction, BT shunt, and atrial septectomy
  2. Bilateral pulmonary artery bands, ductal stent, and atrial septostomy Correct answer.
  3. Bidirectional Glenn, ductal stent, and balloon aortic valvotomy
  4. Pulmonary artery band, ductal ligation, and atrial septectomy

Explanation

The hybrid stage 1 palliation combines bilateral pulmonary artery bands to limit pulmonary blood flow, a ductal stent to secure systemic perfusion, and an atrial septostomy to decompress the left atrium. It avoids cardiopulmonary bypass and arch reconstruction in high-risk neonates.

Question 24Neonatal and Infant Congenital Cardiac Surgery

A neonate with hypoplastic left heart syndrome and a severely restrictive atrial septum is profoundly cyanosed with pulmonary oedema shortly after birth. Which management addresses the underlying problem?

  1. Prostaglandin E1 infusion with close observation
  2. Increasing inspired oxygen and starting inhaled nitric oxide
  3. Emergency creation of an unrestrictive interatrial communication Correct answer.
  4. Diuresis with furosemide and delayed intervention

Explanation

When the atrial septum is restrictive, pulmonary venous blood cannot reach the systemic circulation, producing pulmonary hypertension, oedema and profound desaturation. Urgent septostomy, stent placement or surgical septectomy must precede stage 1 palliation.

Question 25Neonatal and Infant Congenital Cardiac Surgery

A neonate with tetralogy of Fallot and absent pulmonary valve has severe respiratory distress with hyperinflation, and the branch pulmonary arteries are massively dilated. Which feature most directly causes the respiratory compromise?

  1. Severe pulmonary stenosis limiting pulmonary blood flow
  2. Restrictive ventricular septal defect limiting cardiac output
  3. Bronchial compression by the dilated pulmonary arteries Correct answer.
  4. Left ventricular outflow tract obstruction

Explanation

Aneurysmal dilatation of the central pulmonary arteries compresses the tracheobronchial tree, causing air trapping and severe respiratory distress, sometimes with airway malacia. Repair includes reducing and plicating the dilated pulmonary arteries.

Question 26Neonatal and Infant Congenital Cardiac Surgery

A neonate with transposition of the great arteries and an intact ventricular septum is cyanosed shortly after birth. Which initial infusion is most appropriate while arrangements are made for definitive treatment?

  1. Furosemide
  2. Sodium nitroprusside
  3. Prostaglandin E1 Correct answer.
  4. Adrenaline

Explanation

In transposition with intact ventricular septum, systemic and pulmonary circulations run in parallel, so survival depends on mixing at the atrial or ductal level. Prostaglandin E1 keeps the ductus arteriosus open and improves mixing until balloon atrial septostomy or arterial switch can be performed. Vasodilators, inotropes and diuretics do not correct the underlying parallel circulation.

Question 27Neonatal and Infant Congenital Cardiac Surgery

A 10-day-old infant has poor feeding, tachypnoea and feeble femoral pulses. Blood pressure is 95/60 mmHg in the right arm and 55/35 mmHg in the right leg. Which diagnosis best fits these findings?

  1. Coarctation of the aorta Correct answer.
  2. Interrupted aortic arch
  3. Critical aortic stenosis
  4. Pulmonary atresia with intact septum

Explanation

A marked upper-to-lower limb blood pressure gradient with weak femoral pulses is the classic neonatal presentation of coarctation of the aorta. Critical aortic stenosis usually produces weak pulses in all limbs and severe left ventricular dysfunction, while interrupted arch often presents earlier with shock. Pulmonary atresia with intact septum presents with cyanosis rather than upper-limb hypertension.

Question 28Neonatal and Infant Congenital Cardiac Surgery

A 4-month-old with tetralogy of Fallot becomes deeply cyanosed and irritable during a crying episode. Which immediate measure is most appropriate?

  1. Give intravenous atropine and lay flat
  2. Place the infant knee-to-chest and give oxygen Correct answer.
  3. Place the infant supine and give a diuretic
  4. Start high-dose dopamine and intubate electively

Explanation

A hypercyanotic spell reflects increased right-to-left shunting from dynamic subpulmonary obstruction. The knee-to-chest position raises systemic vascular resistance, oxygen improves pulmonary vasodilatation, and morphine or fluid boluses may be added. Diuretics reduce preload and can worsen the spell, while dopamine may increase infundibular obstruction.

Question 29Neonatal and Infant Congenital Cardiac Surgery

Which chromosomal abnormality is most strongly associated with an atrioventricular septal defect in an infant?

  1. Trisomy 21 Correct answer.
  2. 22q11.2 deletion syndrome
  3. Turner syndrome
  4. Marfan syndrome

Explanation

Trisomy 21 (Down syndrome) has the strongest association with atrioventricular septal defects, particularly the complete form. Turner syndrome is linked more with coarctation and bicuspid aortic valve, Marfan syndrome with aortic root disease, and 22q11.2 deletion with conotruncal anomalies.

Question 30Neonatal and Infant Congenital Cardiac Surgery

A neonate with tricuspid atresia and a small ventricular septal defect is cyanosed with duct-dependent pulmonary blood flow. Which initial palliation is most appropriate?

  1. Pulmonary artery banding
  2. A systemic-to-pulmonary shunt Correct answer.
  3. Balloon atrial septostomy alone
  4. Arterial switch operation

Explanation

Tricuspid atresia with restricted pulmonary blood flow requires a reliable source of pulmonary blood flow, usually a modified Blalock–Taussig shunt in the neonatal period. Balloon septostomy improves atrial mixing but does not increase pulmonary flow, and pulmonary artery banding would further reduce it. The arterial switch is used for transposition, not tricuspid atresia.

Question 31Neonatal and Infant Congenital Cardiac Surgery

A 3-month-old with double outlet right ventricle, a subaortic ventricular septal defect and pulmonary stenosis is scheduled for complete repair. Which operation is most appropriate?

  1. Complete Fontan circulation with fenestration
  2. Arterial switch operation with coronary reimplantation and Lecompte maneuver
  3. Bidirectional Glenn anastomosis with shunt takedown
  4. VSD baffle to aorta plus RV-PA conduit Correct answer.

Explanation

Double outlet right ventricle with a subaortic VSD and pulmonary stenosis is repaired by baffling the VSD to the aorta and restoring right ventricle-to-pulmonary artery continuity, often with a conduit. The arterial switch is used for transposition, while Fontan and Glenn procedures are staged palliations for single-ventricle physiology.

Question 32Neonatal and Infant Congenital Cardiac Surgery

A 2-month-old has noisy breathing, stridor and feeding difficulty. Imaging shows a double aortic arch encircling the trachea and oesophagus. Which treatment is most appropriate?

  1. Observation until school age with repeat imaging
  2. Surgical division of the ring Correct answer.
  3. Tracheostomy alone without ring division
  4. Aortopexy without division of the ring

Explanation

A symptomatic double aortic arch causes extrinsic compression of the trachea and oesophagus and is treated by surgical division of the vascular ring, usually by dividing the smaller arch. Observation risks chronic airway injury, and tracheostomy or aortopexy alone does not relieve the encircling compression.

Question 33Neonatal and Infant Congenital Cardiac Surgery

A 4-month-old develops a persistent milky pleural drain after bidirectional Glenn. Which initial nutritional strategy is most appropriate?

  1. High-fat formula supplementation
  2. Low-fat diet with MCT Correct answer.
  3. Standard formula feeding
  4. Total parenteral nutrition with no enteral feed

Explanation

Postoperative chylothorax is initially managed with drainage and a low-fat diet containing medium-chain triglycerides, which are absorbed directly into the portal circulation rather than the lymphatics. If drainage persists, enteral feeding may be stopped and total parenteral nutrition used. High-fat feeds increase chyle flow and worsen the leak.

Question 34Neonatal and Infant Congenital Cardiac Surgery

A 26-week preterm infant has a large patent ductus arteriosus with pulmonary overcirculation. Ibuprofen and indomethacin are contraindicated because of renal impairment. Which management is most appropriate?

  1. Increase positive end-expiratory pressure
  2. Observation until term-equivalent age
  3. Surgical ligation Correct answer.
  4. High-dose furosemide infusion

Explanation

When a haemodynamically significant patent ductus arteriosus cannot be closed medically because of contraindications, surgical ligation is the definitive option. Positive end-expiratory pressure and diuretics may modify symptoms but do not close the ductus. Prolonged observation risks worsening pulmonary overcirculation and bronchopulmonary dysplasia.

Question 35Neonatal and Infant Congenital Cardiac Surgery

A 6-month-old has a systolic murmur, elfin facies and supravalvular aortic stenosis. Which condition is most likely?

  1. Turner syndrome
  2. Williams syndrome Correct answer.
  3. Alagille syndrome
  4. Noonan syndrome

Explanation

Williams syndrome, caused by a 7q11.23 microdeletion, classically produces elfin facies, supravalvular aortic stenosis and peripheral pulmonary stenosis. Turner syndrome is associated with coarctation, Noonan syndrome with pulmonary valve stenosis, and Alagille syndrome with peripheral pulmonary stenosis and bile duct paucity.

Question 36Neonatal and Infant Congenital Cardiac Surgery

A 1-year-old has a sinus venosus atrial septal defect. Which associated anomaly must be sought before repair?

  1. A persistent patent ductus arteriosus
  2. A discrete aortic coarctation
  3. A congenital coronary artery fistula
  4. Partial anomalous pulmonary venous return Correct answer.

Explanation

Sinus venosus atrial septal defects are frequently associated with partial anomalous pulmonary venous return, especially of the right upper pulmonary vein to the superior vena cava. The repair must redirect these veins to the left atrium to avoid persistent left-to-right shunting. Patent ductus arteriosus, coarctation and coronary fistula are not specific associations.

Question 37Neonatal and Infant Congenital Cardiac Surgery

Which finding is the strongest contraindication to completing a Fontan circulation in a child with single-ventricle physiology?

  1. Aortic arch reconstruction during infancy
  2. Previous bidirectional Glenn
  3. Elevated pulmonary vascular resistance Correct answer.
  4. Mild atrioventricular valve regurgitation

Explanation

The Fontan circulation depends on passive pulmonary blood flow, so elevated pulmonary vascular resistance causes low cardiac output and failure of the circulation. Prior arch reconstruction, a previous Glenn and mild atrioventricular valve regurgitation are common and not absolute contraindications. Severe ventricular dysfunction or significant valve regurgitation would also increase risk.

Question 38Neonatal and Infant Congenital Cardiac Surgery

A neonate with pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arteries has cyanosis and confluent central pulmonary arteries. Which long-term surgical strategy is most appropriate?

  1. Pulmonary artery banding
  2. Single-lung transplantation
  3. Staged unifocalization Correct answer.
  4. Primary conduit repair

Explanation

In pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries, the pulmonary blood supply is often segmental and multifocal. Staged unifocalization brings the collaterals together into a single pulmonary supply, after which VSD closure can be considered. Primary conduit repair is generally unsuitable when multiple collaterals supply the lungs, and banding does not address pulmonary atresia.

Question 39Neonatal and Infant Congenital Cardiac Surgery

An infant has a parachute mitral valve, a supravalvular mitral ring, subaortic stenosis and coarctation of the aorta. Which eponym describes this combination?

  1. Scimitar syndrome
  2. Bland-White-Garland syndrome
  3. Ebstein anomaly
  4. Shone complex Correct answer.

Explanation

Shone complex refers to multiple levels of left-sided obstructive lesions, classically a parachute mitral valve, supravalvular mitral ring, subaortic stenosis and coarctation. Ebstein anomaly involves the tricuspid valve, Scimitar syndrome involves anomalous pulmonary venous drainage, and Bland-White-Garland syndrome is anomalous left coronary artery from the pulmonary artery.

Question 40Neonatal and Infant Congenital Cardiac Surgery

A neonate with transposition of the great arteries is considered for arterial switch. Echocardiography suggests an intramural coronary artery. Why does this finding matter?

  1. It mandates a Mustard operation instead of arterial switch
  2. It is a contraindication to prostaglandin E1 infusion
  3. It raises the risk of coronary ischemia after transfer Correct answer.
  4. It makes balloon atrial septostomy unnecessary

Explanation

An intramural coronary course makes coronary transfer during the arterial switch technically demanding and increases the risk of kinking, obstruction and myocardial ischemia. It does not automatically preclude the arterial switch, but it warrants an experienced surgeon and careful planning. Prostaglandin E1 and septostomy may still be required to maintain mixing before surgery.

Question 41Pediatric and Adult Congenital Cardiac Surgery

In the normal fetal circulation, what direction does blood flow take through the ductus arteriosus?

  1. From the right atrium to the left atrium
  2. From the pulmonary artery to the aorta Correct answer.
  3. From the umbilical vein to the inferior vena cava
  4. From the aorta to the pulmonary artery

Explanation

Fetal pulmonary vascular resistance is high, so most right ventricular output leaves the main pulmonary artery through the ductus arteriosus and enters the descending aorta. After birth, pulmonary resistance falls and flow reverses to left-to-right, which is why the vessel is called the ductus arteriosus.

Question 42Pediatric and Adult Congenital Cardiac Surgery

Which ventricular septal defect is most likely to close spontaneously during childhood?

  1. Inlet (atrioventricular canal-type) defect
  2. Subarterial (doubly committed) defect
  3. Perimembranous defect with aortic cusp prolapse
  4. Small muscular (trabecular) defect Correct answer.

Explanation

Small muscular defects have the highest rate of spontaneous closure, usually within the first two years as the ventricular septum grows. Perimembranous, subarterial and inlet defects close less often and more frequently require intervention.

Question 43Pediatric and Adult Congenital Cardiac Surgery

Which combination of findings defines tetralogy of Fallot?

  1. VSD, pulmonary stenosis, overriding aorta, right ventricular hypertrophy Correct answer.
  2. VSD, pulmonary atresia, overriding aorta, biventricular hypertrophy
  3. VSD, aortic stenosis, coarctation, left ventricular hypertrophy
  4. Atrial septal defect, pulmonary stenosis, right aortic arch, left ventricular hypertrophy

Explanation

Tetralogy of Fallot comprises a ventricular septal defect, right ventricular outflow tract obstruction, an overriding aorta and right ventricular hypertrophy. The degree of outflow obstruction, rather than the septal defect itself, determines shunt direction and cyanosis.

Question 44Pediatric and Adult Congenital Cardiac Surgery

In a neonate with d-transposition of the great arteries, what is the main purpose of starting a prostaglandin E1 infusion?

  1. To lower pulmonary blood flow by constricting the pulmonary arteries
  2. To keep the ductus arteriosus open and improve mixing Correct answer.
  3. To close the ductus arteriosus and so prevent pulmonary oedema
  4. To raise systemic vascular resistance and improve coronary perfusion pressure

Explanation

In d-transposition the systemic and pulmonary circulations run in parallel, so survival depends on mixing at atrial, ventricular or ductal level. Prostaglandin E1 maintains ductal patency and improves mixing until a balloon atrial septostomy or the arterial switch operation can be performed.

Question 45Pediatric and Adult Congenital Cardiac Surgery

Which drug is used for pharmacological closure of a haemodynamically significant patent ductus arteriosus in a preterm infant?

  1. Alprostadil
  2. Propranolol
  3. Ibuprofen Correct answer.
  4. Sildenafil

Explanation

Cyclo-oxygenase inhibitors such as ibuprofen and indomethacin constrict ductal smooth muscle and close a significant patent ductus in preterm infants. Alprostadil has the opposite effect and is used to keep the ductus open in duct-dependent lesions.

Question 46Pediatric and Adult Congenital Cardiac Surgery

A 6-year-old presents with upper limb hypertension and weak femoral pulses. Which additional finding is most commonly associated with coarctation of the aorta?

  1. Secundum atrial septal defect
  2. Pulmonary valve stenosis
  3. Ebstein anomaly
  4. Bicuspid aortic valve Correct answer.

Explanation

A bicuspid aortic valve is present in roughly half to two-thirds of patients with coarctation, reflecting a shared developmental mechanism, and may itself require surveillance or intervention. Other recognised associations include ventricular septal defect, patent ductus arteriosus and the Shone complex.

Question 47Pediatric and Adult Congenital Cardiac Surgery

An infant has noisy breathing and choking during feeds, and imaging shows a vascular ring encircling the trachea and oesophagus. Which anomaly most commonly produces a complete vascular ring?

  1. Anomalous left coronary artery from the pulmonary artery
  2. Double aortic arch Correct answer.
  3. Right aortic arch with mirror-image branching
  4. Left aortic arch with aberrant right subclavian artery

Explanation

A double aortic arch encircles both the trachea and the oesophagus with right and left arches, producing stridor, wheeze and feeding difficulty in infancy. An aberrant right subclavian artery from a left arch compresses the posterior oesophagus only and does not complete a ring.

Question 48Pediatric and Adult Congenital Cardiac Surgery

A secundum atrial septal defect lies within which part of the atrial septum?

  1. The fossa ovalis Correct answer.
  2. The superior vena cava–right atrial junction
  3. The coronary sinus wall
  4. The lower septum near the inferior vena cava

Explanation

Ostium secundum defects occur in the region of the fossa ovalis and account for most atrial septal defects. Superior and inferior sinus venosus defects lie at the caval junctions and are frequently accompanied by partial anomalous pulmonary venous connection.

Question 49Pediatric and Adult Congenital Cardiac Surgery

Which cardiac lesion is most characteristic of children with trisomy 21?

  1. Complete atrioventricular septal defect Correct answer.
  2. Tricuspid atresia
  3. Anomalous left coronary artery from the pulmonary artery
  4. d-Transposition of the great arteries

Explanation

Complete atrioventricular septal defect results from failure of endocardial cushion fusion and is strongly associated with trisomy 21. It combines a primum atrial septal defect, an inlet ventricular septal defect and a common atrioventricular valve.

Question 50Pediatric and Adult Congenital Cardiac Surgery

A 2-day-old with cyanosis and severe pulmonary oedema is found to have pulmonary veins draining below the diaphragm into the portal vein. Which statement about this lesion is correct?

  1. It is caused by failure of the septum secundum to form
  2. It typically presents in adolescence with mild exercise limitation
  3. It requires urgent surgical relief of pulmonary venous obstruction Correct answer.
  4. It is associated with decreased pulmonary vascular markings on chest radiograph

Explanation

Infracardiac total anomalous pulmonary venous connection passes through the diaphragm into the portal system, and hepatic sinusoidal resistance causes severe pulmonary venous hypertension. These infants develop pulmonary oedema and cyanosis within the first days of life and need urgent surgical repair.