Patent ductus arteriosus (PDA) is a type of congenital heart defect when the ductus arteriosus does not close after the birth of the infant. The two major arteries, the aorta and the pulmonary artery are linked together by the ductus arteriosus as a part of the fetal blood circulation. The opening of the ductus arteriosus usually closes within minutes or few days after the birth but when it fails, the condition is known as patent ductus arteriosus. This can cause the abnormal blood flow between two of the major arteries that are connected to the heart. The minor form of this condition usually does not present any problems but the large patent ductus arteriosus can weaken the heart muscle resulting in complications and heart failure. This abnormality appears to be more common among the premature infants and occurs in an average of 8 out of 1,000 premature infants.
Symptoms
The symptoms usually differ based on the size of the condition and the maturity of the infants. Although the mild condition may go undetected causing no symptoms, the more severe large PDA can develop symptoms of heart failure soon after the birth of the infant. Usually, the heart murmur is the only indication of PDA which is the abnormal sound during the heartbeat. A large PDA can cause symptoms such as tiredness, rapid heartbeat, poor eating and poor weight gain, sweating with eating, breathlessness or breathing fast.
Causes
Before the birth, the ductus arteriosus is responsible for diverting the blood flow from the lungs while they continue to develop. During this development, the infant receives the oxygen required from the mother. After the birth, the vascular connection should close as the natural process. There isn’t a clear indication of the cause of this congenital heart defect. It is believed that certain genetic and environmental factors appear to play a role. It is also estimated that rubella infection during pregnancy can also cause PDA. It is common in infants with congenital heart problems such as hypoplastic left heart syndrome and pulmonary stenosis. However, the abnormal opening of this system results in too much blood circulation in the baby’s lungs and the heart which can develop various related complications.
Diagnosis
This condition can be detected during the regular check-ups of infants with the heart murmur. If the PDA appears to be small, it may not be detected until later in childhood. In the case the heart defect is suspected, various diagnostic tests may be required. This can include an echocardiogram to determine the function and the potential structural abnormalities of the heart, chest x-rays to identify problems with the heart and the lungs along with the electrocardiogram to monitor the electrical activity of the heart.
Treatment
The goal of the treatment process is to close the PDA which can include medications, catheter-based procedures or surgery. Although the small PDA may close without the need for treatment, the larger ones require treatment, particularly when health problems develop. The catheter-based procedure does not require the surgical opening of the chest to close the PDA enabling quick recovery for the child. The surgery may be required if the infant is too small for the catheter-based procedure or have other health problems due to PDA and is usually not performed until the infant reaches 6 months of age.
References
http://www.mayoclinic.org/diseases-conditions/patent-ductus-arteriosus/basics/treatment/con-20028530
https://medlineplus.gov/ency/article/001560.htm
https://www.nhlbi.nih.gov/health/health-topics/topics/pda/treatment
