©️ Mayo clinic & Cincinnati Children's
Patent Ductus Arteriosus (PDA)
PDA is where there is a persistent opening between the Aorta and the pulmonary artery, present at birth, and is more common in preterm babies than full-term infants. This is a normal physiological phenomenon for fetal blood flow in the womb (allowing blood to bypass the lungs), and usually closes within the first hours after birth. If it does not close however, it is called a patent ductus arteriosus.
This does not cause issues and may not need treatment. However if the PDA is large and lets oxygen-poor blood flow in the incorrect direction, this can weaken the heart muscle, causing heart failure and other complications.
Risk factors
☞ Prematurity
☞ respiratory distress and surfactant treatment
☞ fluid administration
☞ asphyxia
☞ high altitude
☞ congenital heart disease
(All affecting lungs and alveoli)
Symptoms
☞ Fast breathing
☞ Dyspnoea
☞ More respiratory infections
☞ Tire more easily
☞ Poor growth
☞ Small PDAs may not present with any symptoms and may not be discovered until there is evaluation of a heart murmur (extra sound heard when listening to the heart, caused by a turbulence/disturbance in the blood flow through the heart/blood vessels).
PDA is a risk factor for endocarditis.
Diagnosis
PDA causes a distinct heart murmur heard on physical exam. Most often, this murmur, along with symptoms of heart failure in premature infants, most commonly lead to PDA diagnosis.
Chest X-ray shows enlarged heart and increased blood flow to lungs.
Echocardiogram confirms diagnosis, and can determine ductus arteriosus size, and whether the heart chambers are enlarged due to extra blood flow.
Treatment:
Initially, PDA is given a chance to close on its own if the heart failure is under control. If symptoms are severe however, or it is unlikely to close on its own, surgical/medical treatment is necessary.
Medicines work best in newborns. Indomethacin or Ibuprofen constricts the muscle in the wall of the PDA to assist in closing it. However not all babies may receive these due to side effects. Panadol may be used as a second line treatment.
Surgical intervention involves cardiac catheterisation laboratory with device or coil via left intercostal incision, and tying off the ductus arteriosus.
Risk of complications are low.
Graphics for PDA:
Normal:
PDA:
PDA Ligated:
1. PDA shunting blood from aorta to the pulmonary artery.
2. PDA ligated.
Above images: https://www.cincinnatichildrens.org/patients/child/encyclopedia/defects/graphicsummaries/pdags
~~~