NBE Pediatric Echocardiography 5 — Questions and Answers
Question 1: A child with Williams syndrome is referred for echocardiography. Which cardiovascular lesion is most commonly found in this condition?
- Bicuspid aortic valve with stenosis
- Supravalvar aortic stenosis (Correct answer)
- Mitral valve prolapse
- Ebstein anomaly of the tricuspid valve
Correct answer: Supravalvar aortic stenosis
Williams syndrome (elastin gene deletion) is most commonly associated with supravalvar aortic stenosis, characterized by narrowing of the ascending aorta just above the sinuses of Valsalva.
Question 2: During a neonatal echocardiogram, you identify that the pulmonary veins drain into the left atrium but the left atrium connects to the right ventricle via the mitral valve. What is the most likely diagnosis?
- Corrected transposition of the great arteries (L-TGA) (Correct answer)
- Mitral atresia with intact atrial septum
- Atrioventricular discordance with normal great arteries
- Tricuspid atresia
Correct answer: Corrected transposition of the great arteries (L-TGA)
In L-TGA (congenitally corrected transposition), there is both atrioventricular discordance (left atrium connects to right ventricle via mitral valve) and ventriculoarterial discordance.
Question 3: Which Doppler measurement is the gold standard for assessing diastolic dysfunction in children with cardiomyopathy?
- Peak E-wave velocity of mitral inflow alone
- Tissue Doppler imaging of the mitral annulus (e' velocity) combined with E/e' ratio (Correct answer)
- Deceleration time of mitral E wave alone
- Pulmonary vein S/D ratio alone
Correct answer: Tissue Doppler imaging of the mitral annulus (e' velocity) combined with E/e' ratio
Tissue Doppler-derived mitral annular e' velocity and the E/e' ratio provide load-independent assessment of diastolic function and are the preferred parameters in pediatric cardiomyopathy.
Question 4: In a neonate with suspected total anomalous pulmonary venous return (TAPVR), which finding on echocardiography indicates obstructed infracardiac TAPVR?
- Mild right ventricular dilation with normal pulmonary artery pressure
- Small right atrium with left-to-right atrial shunting
- High-velocity turbulent flow in the descending vertical vein below the diaphragm with severe pulmonary hypertension (Correct answer)
- Dilated coronary sinus with left atrial enlargement
Correct answer: High-velocity turbulent flow in the descending vertical vein below the diaphragm with severe pulmonary hypertension
Obstructed infracardiac TAPVR is characterized by high-velocity turbulent flow in the vertical vein as it traverses the diaphragm (portal system obstruction), resulting in severe pulmonary venous hypertension.
Question 5: A 12-year-old athlete has an echocardiogram showing concentric left ventricular hypertrophy with a non-dilated LV cavity. Which condition must be distinguished from athlete's heart?
- Dilated cardiomyopathy
- Hypertrophic cardiomyopathy (HCM) (Correct answer)
- Left ventricular non-compaction
- Restrictive cardiomyopathy
Correct answer: Hypertrophic cardiomyopathy (HCM)
Hypertrophic cardiomyopathy presents with asymmetric or concentric LVH and non-dilated LV, and must be distinguished from athlete's heart because HCM carries risk of sudden cardiac death with exercise.
Question 6: In a child with Ebstein anomaly, which echocardiographic finding defines the severity of tricuspid valve displacement?
- The degree of tricuspid regurgitation severity
- The apical displacement of the septal tricuspid leaflet hinge point relative to the mitral valve insertion (Correct answer)
- The size of the right ventricular outflow tract
- The presence of an atrial septal defect
Correct answer: The apical displacement of the septal tricuspid leaflet hinge point relative to the mitral valve insertion
In Ebstein anomaly, the diagnostic criterion is apical displacement of the septal tricuspid leaflet hinge point ≥8 mm/m² BSA below the mitral valve insertion in the apical 4-chamber view.
Question 7: Which echocardiographic technique provides the most accurate measurement of right ventricular volumes in children with congenital heart disease?
- M-mode measurement of the RV free wall
- 2D area-length method from the apical 4-chamber view
- 3D echocardiography with volumetric analysis (Correct answer)
- Tricuspid annular plane systolic excursion (TAPSE) alone
Correct answer: 3D echocardiography with volumetric analysis
3D echocardiography allows direct volumetric measurement of the asymmetric right ventricle without geometric assumptions, making it the most accurate echocardiographic method for RV volume quantification.
NBE Pediatric Echocardiography 5
A child with Williams syndrome is referred for echocardiography.
Which cardiovascular lesion is most commonly found in this condition?