While in the womb, two major arteries that connect to the heart are joined by one blood vessel known as the ductus arteriosus. It is vital for fetal blood circulation, but it should close within days after birth.
When it fails to close, blood from the pulmonary artery mixes with blood from the aorta and flows the wrong way. The defect is known as Patent ductus arteriosus or PDA. Blood pressure in the arteries of the lungs increases and causes pulmonary hypertension. The heart must work harder and can become damaged. The possible causes of PDA are unclear, but it is thought to be caused by environmental influences or a hereditary defect.
Small PDAs can go unnoticed for decades, but large PDAs can become life-threatening very quickly. Doctors often hear a heart murmur during a routine pediatric exam. The symptoms depend on the severity of the defect and may include:
Doctors are still studying the technical cause of the condition and, aside from the high-risk of contracting PDA amongst premature children and that it is more commonly found in girls, they are not sure of its origins. In order to diagnose PDA doctors typically listen to the rhythms of a child’s heart. PDA can commonly cause a heart murmur (a strange or doubled heartbeat) which doctors will often find using a stethoscope. In some cases, a chest X-ray might be needed as well to more closely examine the baby’s lungs and heart. However, babies born prematurely might have different symptoms from children carried full-term. In this case, more PDA tests may need to be conducted.
Some other tests used to detect PDA include:
An echocardiogram utilizes sound waves to capture an image of the child’s heart. This painless imaging technique allows doctors to see the shape and size of the heart. Additionally, doctors can see if there are any issues or abnormalities in blood flow to and from the heart. Aside from a stethoscope, an echocardiogram is the most commonly used test to diagnose PDA.
The EKG records the heart’s electrical activity detecting irregular or odd heart rhythms, while also identifying the presence of an enlarged heart.
In some cases the PDA will shrivel and close by itself. However, life-threatening complications can occur if the PDA is large and goes uncorrected. The heart can weaken, enlarge and eventually fail. Arrhythmias and infection can also occur. Treatment depends on the severity of the PDA and may include:
Prognosis is good for otherwise healthy kids when a patent ductus arteriosus is treated.
In order to reduce the chances of a baby developing PDA, pregnant women should: