Persistent ductus arteriosus



Ductus arteriosus connects pulmonary artery at its bifurcation to the descending aorta immediately distal to the origin of left subclavian artery. In foetal life it (PDA) diverts the blood from pulmonary artery to aorta. If it (PDA) persists blood from aorta passes to pulmonary artery. In long term the shunt is reversed in presence of sever pulmonary hypertension which is called Eisenmenger’s syndrome.

Clinical features:

Symptoms: Usually absent for many years. Symptoms arise when Eisenmenger’s syndrome develops, e.g. Dyspnoea, fatigue and features of cardiac failure.

Signs:

1.      General: Growth retardation, central cyanosis.
2.      CVS:
a)      Pulse: Large volume, collapsing.
b)      BP: Low diastolic pressure, increased pulse pressure.
c)      LVH: Apex beat shifted downwards and outwards.
d)      Thrill over pulmonary area.
e)      Murmru:
·         Gibson’s murmur.
·         Apical mid-diastolic murmur.

Investigations:

1.      Chest X-ray:
·         Enlargement of heart.
·         Prominent pulmonary artery.
·         Plethoric lung fields.
2.      ECG finding:
·         Usually normal.
·         LVH may present.
3.      Echo:
·         RA and RV dilatation.
·         Demonstration of duct in cross sectional echo.

Management:

1.      Premature infants with PDA: Medical treatment with indomethacin or ibuprofen (used in first week of life to induce closure).
2.      Surgical: Closure of patent ductus at cardiac catheterization with an implantable occlusive device.
3.      Older children and adults with small shunt: Medical management, prophylaxis against infective endocarditis.

Reference:

1.      Davidson’s Principles and Practice of Medicine, 21st edition.
2.      Wikipedia the free encyclopedia.


মন্তব্যসমূহ