Patent Ductus Arteriosus (PDA): Information on Causes, Diagnosis & Treatments
Patent ductus arteriosus (PDA) is a serious congenital heart problem that can develop after birth involving the abnormal flow blood between the heart's two major arteries. Prior to the baby's delivery, two major arteries and the heart's pulmonary and aorta arteries are connected by the ductus arteriosus, a crucial vessel for blood circulation of the fetus. However, just after birth or a few days after delivery, the vessel closes, allowing the normal change to occur in blood flow circulation.
However, the normal closure of the ductus arteriosus remains open because of the defect, allowing oxygenated blood moving through the aorta to blend with oxygen deprived blood returning to the heart from the pulmonary artery. The open vessel places a strain on the heart and causes an increase in the blood pressure in the arteries of the lung.
Many newborns with the patent ductus arteriosus congenital heart defect also suffer from other heart problems that might exacerbate the problem of decreasing oxygenated blood flow to the body. If the heart defect is small, it might not produce any problems or ever require treatment or repair. However, if the patent ductus arteriosus is large and does not receive the proper treatment, it can allow oxygen-depleted blood to flow backward leading to heart failure and/or another complication including a weakened heart muscle.
Doctors have numerous treatment options for the condition including ongoing monitoring, drugs, surgical procedures, or closing the opened blood vessel through cardiac catheterization.
- Who Is at Risk for Patent Ductus Arteriosus?
- Common Symptoms
- Diagnosing Patent Ductus Arteriosus
- Treating the Condition
Who Is at Risk for Patent Ductus Arteriosus?
Patent ductus arteriosus is congenital, meaning that the development of the condition can occur prior to birth, or just after the baby is born. However, there are certain risk factors associated with the condition that increase the potential for its development. These include:
- Premature Birth – Babies who are born prematurely are more likely to develop patent ductus arteriosus compared to newborns who were delivered at full-term.
- Genetic Predisposition and Family History – Genetics can play a key role in the development of patent ductus arteriosus especially if the child suffers from Down syndrome or other genetic condition or the family has a history of heart defects.
- Pregnancy-Related Rubella Infection – If the pregnant mother contracts rubella (German measles) while pregnant, the newborn has an increased potential risk of being born with patent ductus arteriosus. This is because the rubella virus that causes German measles has the ability to cross the placenta and enter the fetus' blood circulatory system. Rubella is known to damage the heart, blood vessels, and other organs.
- High Altitude Deliveries – Delivering a baby at an altitude higher than 10,000 feet can significantly increase the newborns potential of developing patent ductus arteriosus compared to newborns who were birthed at a lower altitude.
Because the ductus arteriosus fails to close normally, the defect allows too much blood to circulate and of the heart and lungs of the baby. Without treatment or repair, the child could suffer from pulmonary hypertension that leaves the heart weakened and enlarged.
Many babies who are born with small patent ductus arteriosus defects might not suffer any complications. However, larger defects left untreated could produce serious problems including:
- Pulmonary Hypertension – Developing pulmonary hypertension (high blood pressure in the lungs) is a serious complication associated with patent ductus arteriosus that can eventually lead to permanent lung damage. Without appropriate treatment, a child suffering from patent ductus arteriosus can develop Eisenmenger syndrome, a serious irreversible condition associated with high blood pressure.
- Heart Failure – The condition can lead to an enlarged and weakened heart eventually resulting in heart failure where the heart lacks the ability to effectively pump blood throughout the body.
- Endocarditis – Patent ductus arteriosus can cause structural heart problems that eventually lead to endocarditis, an infection of the heart where the interlining becomes inflamed.
- Pregnancy – Pregnant mothers who suffer from small patent ductus arteriosus can usually tolerate the pregnancy, labor, and delivery without any significant issues. However, if the condition has complications or the defect is large in size, the mother may have an elevated risk of complications including pulmonary hypertension, arrhythmia, or heart failure. If the mother suffers from Eisenmenger syndrome, her health, and the life of her baby, could be threatened. Because of that, pregnant mothers with a heart defect should discuss all the risks associated with bringing the child to full-term.
The type and severity of the sums associated with patent ductus arteriosus differ between newborns and mothers who suffer from their own heart defect. In addition, if the child is born prematurely, the symptoms might be more significant compared to full-term babies who have symptoms that may be undetected for days, weeks or years. However, if the defect is large, it can produce significant heart failure within hours or days after birth.
Usually, a diagnosis of patent ductus arteriosus is the result of suspected heart defects right after the child was born. The doctor will look for obvious symptoms associated with the condition including heart murmur's that can be identified through a stethoscope. The newborn might display signs of a large patent ductus arteriosus just after being born, during their infancy years, or throughout their childhood.
The most common patent ductus arteriosus symptoms include:
- Easy tiring
- Sweating when eating or crying
- Poor eating habits
- Diminished growth
- Rapid heart rate
- Persistent breathlessness or breathing quickly
The parents should consider taking the baby to see the doctor if certain symptoms persist including:
- Unexpected weight loss or a lack of weight gain as the child ages
- Tiring easily when playing or eating
- Breathing rapidly or being continuously out of breath
- Breathlessness associated with crying or eating
Diagnosing Patent Ductus Arteriosus
An accurate diagnosis for patent ductus arteriosus is usually the result of listening to the child's heartbeat through a stethoscope. Hearing the identifiable heart murmur can lead the doctor or diagnostician to recommend various tests that include:
- Echocardiogram – Using a machine that produces images using sound ways can help the doctor identify the signs and symptoms associated with patent ductus arteriosus. This includes enlarged heart chambers or another potential heart defect.
- Chest X-Rays – X-ray images help identify any heart defect or the functioning condition of the lungs and heart.
- Electrocardiogram – An ECG machine records the heart's electrical activity that can be used to diagnose rhythm problems associated with a heart defect.
- Cardiac Catheterization – The doctor may choose to insert a cardiac catheter in the child's leg. The flexible, long catheter can be inserted into the interior of the heart to allow an examination of the defect that might have been first identified using an echocardiogram, electrocardiogram, or chest x-ray.
Treating the Condition
Based on the severity of the condition, the doctor may choose one or more treatments to repair or manage the problem that includes:
- Watchful Waiting
- Open-Heart Surgery
Many individuals who have been born with patent ductus arteriosus at birth or later in life are required to take antibiotic medications before undergoing some surgical procedures and dental work to prevent infected endocarditis, serious and life-threatening heart infection. In addition, implementing a preventative antibiotic medication regimen may be necessary within the first six months after the repair has been made on the child's heart.