Congenital heart diseases ( acyanotic particularly topic enclosed with patent ductus arteriosus )

1. Congenital heart diseases
PDA ( patent ductus
arteriosus)
Balashankaramoorthy
MBBS Final year

5. • is a congenital anomaly in which the ductus
arteriosus remains open after birth .
• this produces a persistent communication between
the proximal left pulmonary artery and the
descending aorta .
• since the pressure in the aorta is higher than that in
pulmonary artery , it produces continuous
arterioventricular left to right shunt the volume
depends on the size of the ducts
• About 50% of the left ventricular output is
reciruclated through the lungs with a consequent
increase in the work of the heart .

6. SYMPTOMS :
More common in female to male ratio of about 2:1 .
If the shunt is small then it may be asymptomatic for
years .
if the shunt is moderate to large there is retardation of
growth & development , it produces left heart volume
overload
cardiac failure may develop producing dyspnea .
in some cases it may raise pulmomary artery pressure
resulting in pulmonary hypertensiom & eisenmengers
syndrome .

7. • persistent ductus with reversed shunting :
• when the pulmonary vascular resistance increases ,
pulm artery pressure increase until it equals or
exceeds aortic pressure .
• then the shunt through the pda may reverse causing
eisenmengers syndrome .
• patient with eisenmengers syndrome are cyanotic
and may have differential cyanosis .
• it is characterised by clubbing of the toes but not the
fingers because right to left ductal shunting is distal
to the subclavian arteries .

9. • Chest XRAY ( shows enlargement of pulm.artery with
increased vascular markings - plethoric fields )
• Ecg usually normal with small ductal shunts , it may
demonstrate left atrial enlargement left ventricular
hypertrophy , sinus tachycardia or atrial fibrillation
in patients with moderate to large shunts .
• Echo & colour doppler shows pda & anount of blood
flow through the ductus arteriosus .
• MRI & CT it can assess the degree of calcification
which is important in case of surgicsl therapy is
considered .

11. • Small ductus arteriosus may predispose to endarteritis and
ductus closure should be done unless clinically silent .
• Ductus closure is indicated for any child or adult who is
symptomatic from significant left to right shunting through the
PDA
• Transcatheter occluding devices ( eg . coils , buttons and
umbrellas ) are increasingly used .
• Video guided thoracoscopic clip closure
• Surgical ligation or division of the pda remaims the treatment
of choice for the rare very large ductus arteriosus
• symptomatic patients with PDA usually improves with a
medical regimen of diuretics , digoxin and ACE inhibitors ,
antidysarythmia medications , anticoagulation may be useful in
patients with atrial fibrillation / flutter

12. • 1st week of life ( if ductus is patent )- prostaglandin
synthetase inhibitors (like indomethacin or ibuprofen
) may be useful which induce the closure.
• However if there is an imapired lung perfusion (eg
severe pulm.stenosis and left to right shunt through
the ductus ) the ductus must be kept open with
prostaglandin treatment to improve oxygenation .

13. Thankyou
Happy learning cardiology