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Week 3 Case Study
You are examining a 5-week old infant and hear a systolic murmur at the lower left
sternal border. You suspect a ventricular septal defect. The parents are concerned
and have several questions.
What is the cause of a ventricular septal defect?
A ventricular septal defect means that there is a small opening in the wall
(septum) that separates the right and left sides of the baby’s heart. Ventricular septal
defects develop during fetal cardiac formation when the septum dividing the ventricles
fails to close completely. The cause may be multifactorial and linked to chromosomal
abnormalities such as trisomy 21 or 13, maternal conditions like uncontrolled diabetes, or
teratogenic exposures during pregnancy. In many infants, however, the exact cause
remains idiopathic and isolated to abnormal embryologic development of the ventricular
wall (Ball et al., 2023).
What problems will our baby have due to his VSD?
Most babies with small ventricular septal defects have few or no problems at all,
and many grow and develop normally. In some cases, when the opening is larger, the
heart has to work harder to pump blood, which can make a baby breathe faster, feed more
slowly, or tire easily during feeding. Sometimes, babies may not gain weight as quickly
as expected. If the heart is working extra hard, fluid can build up in the lungs, leading to
Week 3 Case Study
You are examining a 5-week old infant and hear a systolic murmur at the lower left
sternal border. You suspect a ventricular septal defect. The parents are concerned
and have several questions.
What is the cause of a ventricular septal defect?
A ventricular septal defect means that there is a small opening in the wall
(septum) that separates the right and left sides of the baby’s heart. Ventricular septal
defects develop during fetal cardiac formation when the septum dividing the ventricles
fails to close completely. The cause may be multifactorial and linked to chromosomal
abnormalities such as trisomy 21 or 13, maternal conditions like uncontrolled diabetes, or
teratogenic exposures during pregnancy. In many infants, however, the exact cause
remains idiopathic and isolated to abnormal embryologic development of the ventricular
wall (Ball et al., 2023).
What problems will our baby have due to his VSD?
Most babies with small ventricular septal defects have few or no problems at all,
and many grow and develop normally. In some cases, when the opening is larger, the
heart has to work harder to pump blood, which can make a baby breathe faster, feed more
slowly, or tire easily during feeding. Sometimes, babies may not gain weight as quickly
as expected. If the heart is working extra hard, fluid can build up in the lungs, leading to
