The ductus arteriosus is a fetal vessel between the aorta and the pulmonary artery that normally closes in the first days after birth. When it stays open, blood shunts from the aorta to the lungs; this is common in premature babies and can cause heart failure if the opening is large.
Key symptoms
- Small PDA: often no symptoms
- Fast breathing and poor feeding in infants
- Poor weight gain and sweating with feeds
- Frequent chest infections; breathlessness on exertion in older children
What you find on exam
- Continuous machine-like murmur below the left clavicle
- Bounding pulses and wide pulse pressure
- Active precordium
- Pink arms and blue legs if pulmonary pressure becomes high
Tests
- Echocardiogram with Doppler to confirm it and measure its size
- Chest X-ray: large heart and more lung blood flow in large shunts
- ECG: left ventricular hypertrophy in large shunts
- Oxygen saturation in an arm and a leg
Treatment basics
- Premature infants: indomethacin, ibuprofen or acetaminophen to close it
- Fluid limits and diuretics for heart failure
- Transcatheter device closure or surgical ligation if it stays open and is significant
- Alprostadil to keep it open in duct-dependent heart defects
Red flags
- Signs of heart failure in an infant
- Feeding intolerance or bloody stool in a premature baby (necrotizing enterocolitis)
- Blue lower body that suggests pulmonary hypertension
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.