Differential Diagnosis for a 12-hour-old Girl with a Murmur
The patient's presentation with a murmur, cyanosis of the hands and feet, and a normal pulse oximetry reading suggests a cardiac etiology. The following differential diagnoses are considered:
- Single most likely diagnosis
- Patent Ductus Arteriosus (PDA): The presence of a midsystolic ejection murmur at the upper left sternal border with radiation to the back is consistent with PDA. The cyanosis of the hands and feet (differential cyanosis) can occur in PDA, especially if there is right-to-left shunting.
- Other Likely diagnoses
- Aortic Coarctation: The murmur's location and radiation, along with differential cyanosis, could suggest coarctation of the aorta. However, the presence of symmetric peripheral pulses and normal capillary refill time makes this less likely.
- Ventricular Septal Defect (VSD): A VSD could present with a similar murmur, but the lack of other signs such as a gallop or increased respiratory distress makes it less likely.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Hypoplastic Left Heart Syndrome (HLHS): Although less likely given the patient's relatively stable condition and lack of severe respiratory distress, HLHS is a critical diagnosis that requires prompt recognition and treatment.
- Total Anomalous Pulmonary Venous Connection (TAPVC): This condition can present with cyanosis and a murmur, and it is essential to consider it in the differential diagnosis due to its high mortality rate if left untreated.
- Transposition of the Great Arteries (TGA): TGA is another critical diagnosis that can present with cyanosis and requires prompt recognition and treatment.
- Rare diagnoses
- Tricuspid Atresia: This congenital heart defect can present with cyanosis and a murmur, but it is less common and would typically be associated with more severe symptoms.
- Pulmonary Atresia: This condition can also present with cyanosis and a murmur, but it is rare and would typically be associated with more severe respiratory distress.
Given the patient's presentation, the best next step in management would be to perform an echocardiogram to confirm the diagnosis and guide further management. This would help to differentiate between the possible diagnoses and identify any potential life-threatening conditions that require prompt intervention.