Patent ductus arteriosus
Patent ductus arteriosus (PDA) is a condition where the ductus arteriosus does not close after birth. It is the second most common congenital heart disease affecting approximately 1 in 1600 to 5000 live births in the US.
The ductus arteriosus shunts blood from the pulmonary artery to the aorta bypassing the lungs. It closes soon after birth by a complex process that is regulated by oxygen tension and decreases in prostaglandin E2. In a PDA, the vessel fails to close, resulting in transmission of blood between the aorta and the pulmonary artery. This shunting, or transmission of blood, allows some oxygenated blood from the aorta, which has a higher pressure, to the pulmonary artery, which has the lower pressure. If the shunt is large enough, the infant may become short of breath due the increase fluid return to the lungs, increased lung pressure, and thus increased energy demands to fill the lungs.
Some congenital heart defects, such as transposition of the great vessels, are incompatible with life and a PDA may be neccessary in keeping the infant alive by allowing oxygenated and deoxygenated blood to mix. In these cases prostaglandins are used to keep the ductus arteriosus open.
- Continuous machine like heart murmur
- Differential cyanosis (cyanosis of lower extremities and not the upper extremities)
- Widened Pulse Pressure
- Acute Pericarditis
- Aortopulmonary Septal Defect
- Coarctation of the Aorta
- Coronary Artery Fistula
- Pediatric Acute Respiratory Distress Syndrome
- Pediatric Sinus of Valsalva Aneurysm
- Pediatric Tachycardia
- Pulmonic Valvular Stenosis
- Sickle Cell Anemia
- Tetralogy of Fallot With Absent Pulmonary Valve
- Careful physical examination demonstrating characteristic machine like murmur
Laboratory tests are usually not helpful. MRA and Cardiac CT can also be used as diagnostic tools
Spontaneous closure is usually common but if significant respiratory distress or impaired oxygen delivery is present, therapy is usually required.
IV indomethacin is usually effective when administered in the first 10-14 days of life.
Cardiac catheterization and catheter closure in addition to surgical ligation are also options if medical therapy fails.
- Mitchell, S. C., Korones, S. B., Berendes, H. W. Congenital heart disease in 56,109 births: incidence and natural history. Circulation 43: 323-332, 1971.
- Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436