Review Question - QID 106578

A 4-year-old with dyspnea and fatigue on exertion with a normal prenatal course, no other significant abnormalities, and a holosytolic murmur along the left sternal border is most likely suffering from a ventricular septal defect (VSD).

VSDs are the most common congenital heart defect, followed by ASDs, and most VSDs close by the time children are 2 years old. They are typically asymptomatic, but depending on the size of the defect, can become symptomatic as the left-to-right shunt causes pulmonary congestion, leading to pulmonary hypertension over a long period of time. This pulmonary hypertension can lead to right heart strain with a reversal of the shunt to a right-to-left shunt, termed Eisenmenger's syndrome. These symptomatic VSDs are typically corrected surgically after diagnostic imaging via echocardiogram for confirmation. New guidelines suggest that these patients do not require antibiotic prophylaxis unless the VSD has been surgically repaired with a foreign material.

Frank et al. discuss the evaluation of heart murmurs in the pediatric population and red flags that warrant further evaluation. These murmurs include holosystolic or diastolic murmur, grade 3 or higher murmur, harsh quality, an abnormal S2, maximal murmur intensity at the upper left sternal border, a systolic click, or increased intensity when the patient stands. They state that diagnosis should depend on several key factors including family history of sudden cardiac death or congenital heart disease, in utero exposure to certain medications or alcohol, maternal diabetes mellitus, history of rheumatic fever or Kawasaki disease, and genetic disorders such as chromosomal disorders.

Mosimann et al. discuss the outcomes of VSDs following surgical repair. They state that of all VSDs diagnosed in an intrauterine fashion, 49% cases resulted in intrauterine death or termination, and postnatal death occurred in 9% of cases. Of the neonates that were successfully delivered, 29% were surgical candidates. Further, of these surgical candidates, 100% survived post VSD repair.

Illustration A shows the two most common types of VSDs. Illustration B shows an echocardiographic image of a moderate ventricular septal defect.

Incorrect Answers:
Answer 1: Endocardial cushion defects are most common in patients with Trisomy 21 (Down's Syndrome). This patient has an otherwise normal physical exam with no abnormalities on genetic testing. Endocardial cushion defects would also present earlier as cyanotic heart defects.
Answer 2: Tetralogy of Fallot typically presents as a cyanotic defect during periods of stress (such as the child crying, being anxious) known as "tet spells." They typically present as systolic murmurs in the upper left sternal border and can be relieved with knees to chest.
Answer 3: PDAs are common in patients with congenital rubella infections. This patient had a normal prenatal course. The murmur of PDAs is typically a murmur that is described as constant, machine-like murmur, along the upper left sternal border.
Answer 5: ASDs typically present with a wide, fixed split of S2. They are not typically symptomatic.