RNC-NIC Neonatal Cardiovascular Assessment and Care 2 — Questions and Answers
Question 1: Which congenital heart defect is classically associated with a 'boot-shaped' cardiac silhouette on chest X-ray?
- Transposition of the great arteries
- Tetralogy of Fallot (Correct answer)
- Total anomalous pulmonary venous return
- Truncus arteriosus
Correct answer: Tetralogy of Fallot
Tetralogy of Fallot causes right ventricular hypertrophy and reduced pulmonary blood flow, resulting in an upturned cardiac apex (boot or coeur en sabot appearance) on chest X-ray.
Question 2: Tetralogy of Fallot consists of which four anatomical abnormalities?
- VSD, ASD, PDA, and coarctation of the aorta
- VSD, pulmonary stenosis, overriding aorta, and right ventricular hypertrophy (Correct answer)
- ASD, VSD, aortic stenosis, and left ventricular hypertrophy
- PDA, VSD, pulmonary hypertension, and tricuspid atresia
Correct answer: VSD, pulmonary stenosis, overriding aorta, and right ventricular hypertrophy
Tetralogy of Fallot is defined by a VSD, pulmonary stenosis (obstruction to right ventricular outflow), an aorta that overrides the VSD, and resultant right ventricular hypertrophy.
Question 3: Prostaglandin E1 (PGE1) is initiated in a neonate with suspected ductal-dependent congenital heart disease. What is its primary mechanism of action?
- Increases cardiac contractility and heart rate
- Decreases pulmonary vascular resistance
- Maintains or reopens the ductus arteriosus (Correct answer)
- Reduces systemic vascular resistance
Correct answer: Maintains or reopens the ductus arteriosus
PGE1 stimulates prostaglandin receptors in the ductal wall to relax smooth muscle, maintaining ductal patency and preserving pulmonary or systemic blood flow in duct-dependent lesions.
Question 4: A neonate diagnosed with transposition of the great arteries (TGA) is hemodynamically unstable. Which intervention is most critical to improve oxygenation before surgical repair?
- Indomethacin infusion to close the ductus arteriosus
- Balloon atrial septostomy (Rashkind procedure) to improve intracardiac mixing (Correct answer)
- Immediate arterial switch operation within the first hour of birth
- High-frequency oscillatory ventilation
Correct answer: Balloon atrial septostomy (Rashkind procedure) to improve intracardiac mixing
Balloon atrial septostomy creates or enlarges an atrial communication, allowing mixing of oxygenated and deoxygenated blood and dramatically improving systemic oxygen delivery in TGA.
Question 5: Which statement about ventricular septal defects (VSD) in newborns is most accurate?
- All VSDs require surgical repair within the first week of life
- Small, muscular VSDs frequently close spontaneously within the first year of life (Correct answer)
- VSDs always produce audible murmurs immediately at birth
- VSDs are the least common congenital heart defect diagnosed in neonates
Correct answer: Small, muscular VSDs frequently close spontaneously within the first year of life
Small muscular VSDs commonly close spontaneously as the muscular septum grows; the decision to intervene is based on size, location, and hemodynamic significance.
Question 6: A neonate with hypoplastic left heart syndrome (HLHS) is awaiting the Norwood procedure. Which management strategy is CONTRAINDICATED in the preoperative period?
- Prostaglandin E1 infusion to maintain ductal patency
- Administration of supplemental oxygen above room air (Correct answer)
- Monitoring four-extremity oxygen saturations
- Nasogastric tube feedings to support caloric intake
Correct answer: Administration of supplemental oxygen above room air
Supplemental oxygen lowers pulmonary vascular resistance, increasing pulmonary blood flow and stealing from the systemic circulation, worsening systemic hypoperfusion in single-ventricle HLHS physiology.
Question 7: Which chest X-ray finding is classically described as an 'egg on a string' appearance and is associated with which congenital heart defect?
- Boot-shaped heart; Tetralogy of Fallot
- Snowman sign; total anomalous pulmonary venous return
- Egg on a string; transposition of the great arteries (Correct answer)
- Box-shaped heart; Ebstein anomaly
Correct answer: Egg on a string; transposition of the great arteries
Transposition of the great arteries produces a narrow superior mediastinum (due to the parallel relationship of the great vessels) and an oval cardiac silhouette, creating the 'egg on a string' appearance.
RNC-NIC Neonatal Cardiovascular Assessment and Care 2
Which congenital heart defect is classically associated with a 'boot-shaped' cardiac silhouette on chest X-ray?