Classically continuous machinery murmur left subclavicular . Patent ductus arteriosus carries a high risk of endocarditis
- Common in premature babies
- PGE keeps PDA open and NSAIDs close PDA
- Premature babies or female births at altitude
- Maternal rubella in first trimester
- Fetal alcohol syndrome
- Female-to-male ratio, 2:1
- Fetal life, the ductus arteriosus allows most of the blood leaving the right ventricle to bypass the pulmonary circulation and pass into the descending aorta.
- This closes hours after birth but can persist post-birth and is an abnormal connection between the pulmonary trunk and descending aorta
- There is continuous flow into the pulmonary circulation
- Shunt volume is determined by the size of the connection and the pulmonary vascular resistance
Dynamic response to chemicals
- Prostaglandin E2 (PGE2) maintains patency
- NSAIDs inhibit PG production cause fetal closure of the ductus arteriosus.
- Infant: SOB, Sweating, poor feeding, weight loss or no weight gain.
- Left subclavicular thrill, Enlarged left heart and apical heave
- Continuous machinery murmur, Wide pulse pressure and bounding pulse
- Signs of Endocarditis must always be considered
- Eisenmenger's there is PA to Aortic flow with cyanosis of the lower limbs and clubbing of the toes but not the fingers.
- FBC, U&E, CRP ? infection ? Endocarditis
- ECG: may be normal or T wave and ST changes
- B-type natriuretic peptide: may be elevated and can help guide treatment
- CXR: pulmonary plethora (high volume going via lungs) Cardiomegaly
- Echocardiogram: PDA best seen parasternal short axis view and from the suprasternal notch
- Cardiac (right/left heart). Catheterization and Angiography: assess size and anatomy
- Spontaneous closure of the patent ductus arteriosus (PDA) is common
- Failure to close then IV indomethacin or ibuprofen is frequently effective in closing a patent ductus arteriosus (PDA) if it is administered in the first 10-14 days of life. Other drugs include Aspirin
- Medical management of heart failure e.g. diuretics, Digoxin
- Transcutaneous: All should be closed due to the real risk of Endocarditis. Most can now have a percutaneous route to close the patent ductus arteriosus (PDA) using an Amplatzer duct occluder. Even if not completely occluded the PDA will usually thrombose.
- Surgical: Surgical ligation or surgical ligation and division remain the standard treatment of large patent ductus arteriosus. Low-risk procedure in the hands of an experienced pediatric cardiovascular surgeon
- Keeping PDA open: sometimes in cyanotic disease keeping the PDA open is important. The ductus arteriosus in neonates and infants is highly sensitive to vasodilatation by PGE1. Patency of the ductus is necessary in patients with cyanotic heart disease until surgical correction of the heart problem is undertaken. This will ensure additional oxygenation of the blood. Administration of PGE1 has been found to be highly effective in such cases.