Make the Diagnosis: Fall 2023

A 5-day-old infant was referred to the Emergency Department from her primary care doctor with tachypnea, a heart murmur, and decreased oral intake. She was born via cesarean section due to a breech presentation following an uncomplicated pregnancy. She was briefly in the NICU for respiratory distress, but was discharged home on day of life 3.

In the emergency department her labs were notable for hypoglycemia but were otherwise reassuring. Blood, urine, and cerebrospinal fluid cultures were sent, and she was started on antibiotics. A chest X-ray showed cardiomegaly and concern for pulmonary vascular congestion. An echocardiogram demonstrated 2 small ventricular septal defects but was otherwise structurally and functionally normal. She was started on a nasal cannula for tachypnea and was admitted to the neonatal intensive care unit for continued evaluation and management.

What is an important diagnosis to consider in this infant?