Patent ductus arteriosus is a congenital heart condition in which the ductus, a small opening or pathway between the pulmonary and aortic valves present in all unborn children, remains open or patent. In most cases, the ductus closes within a day after birth. However, in patent ductus arteriosus, the ductus remains open, causing blood to mix between the two valves.
Two problems are caused by patent ductus arteriosus. Blood flows from left to right, creating overflow of blood to the lungs through the pulmonary valve. This can result in higher than normal pressure in the lungs and may lead to a persistence of high pulmonary pressure, which can only be addressed by lung transplant. Additionally, the aortic valve sends not only oxygenated but also unoxygenated blood to the body, which over time can result in poor growth and clubbing of the extremities.
In most cases, patent ductus arteriosus is so small that these effects are not significant. Frequently, a cardiologist will evaluate newborns with patent ductus arteriosus regularly to see if the ductus will close on its own. Physicians determine that the ductus is still patent by hearing a heart murmur with a stethoscope.
If the newborn is thriving, then initial pediatric visits will continue to check this murmur. However, if the newborn exhibits poor growth, breathing difficulties or cyanosis, the parents are referred to a pediatric cardiologist for complete diagnosis, usually through echocardiogram. Most children with patent ductus arteriosus never need medical intervention, as the ductus will ultimately close.
Patent ductus arteriosus, like most heart defects, is relatively uncommon, with one notable exception. Premature infants have a high risk for the condition. In babies with very low birthrates, 30% may have patent ductus arteriosus.
Because of the immaturity of the lungs in premature children, the effects are far more severe and often necessitate early repair. Any type of surgery performed on a premature child has greater risks for hemorrhage, stroke and respiratory failure than surgeries performed on children with well-developed anatomy. Patent ductus repairs, however, do not pose much risk, and most are done successfully.
In older children, repair by catheterization is generally chosen because it is considered minimally invasive and does not require general anesthesia. Catheterization repair inserts a tiny catheter into one of the main arteries, usually in the thigh. A coil device on the top of the catheter is released once the ductus is reached. It successfully blocks the ductus, inhibiting further exchange of blood between the pulmonary and aortic arteries.
Spring coil technology has an excellent rate of success. Most children who have this surgery need no further medical intervention and have a similar life expectancy to their peers. Cardiologists may follow the child for a time after the repair to ensure the ductus has been completely closed. They may also recommend antibiotic prophylaxis before dental procedures. In general however, there are no activity restrictions on the child with repaired patent ductus arteriosus, and he or she can be expected to live a normal and healthy life.
