Patent ductus arteriosus
Patent ductus arteriosus is persistence of the fetal ductus connecting the aorta and pulmonary artery, causing a continuous machinery murmur and a left-to-right shunt. In preterm infants it is treated with prostaglandin inhibitors; in others it is closed by transcatheter device or surgery, before pulmonary vascular disease develops.
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What this article covers
- Overview
Definition: patent ductus arteriosus (PDA) is persistence, beyond the neonatal period, of the fetal ductus arteriosus connecting the descending aorta and the pulmonary artery.
- Epidemiology
Common, especially in preterm infants. Associated with congenital rubella and high altitude.
- Risk factors
Prematurity (the strongest association). Congenital rubella syndrome.
- Pathophysiology
Failure of ductal closure: the normally closing ductus remains patent after birth.
- Clinical features
A continuous machinery murmur at the left infraclavicular region.
- Differential diagnosis
Venous hum: a benign continuous murmur that varies with head position, distinguished from PDA because it disappears with neck compression or when supine, unlike the fixed machinery murmur.
- Diagnosis
Establish and characterize with echocardiography demonstrating ductal flow: the diagnostic basis is echocardiography visualizing the ductus and continuous flow from the aorta to the pulmonary artery…
- Management
First-line in preterm infants, close with a prostaglandin inhibitor: indomethacin or ibuprofen (a prostaglandin synthesis inhibitor) given as a 3-dose course promotes ductal closure; acetaminophen…
- Complications
Heart failure and pulmonary hypertension.
- Prognosis
Excellent after closure of an isolated duct.
- Prevention
Timely closure of significant ducts. Endocarditis and endarteritis prevention counseling.
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