Patent Ductus Arteriosus

Dr. Kalpana MallaMBBS MD (Pediatrics) Manipal Teaching Hospital

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Patent ductus arteriosusClick to edit Master text stylesPersistence ofSecond level

Third level

ductus arteriosus Closes spontaneously in normal term infants at 3-5 days of age

Fourth level Fifth level

Patent ductus arteriosus5-10 % of CHDs More common in premature infants Male: female ratio is 1:3 Higher incidence of PDA in infants born at high altitudes (> 10,000 feet)

Patent Ductus Arteriosus (PDA)Usually closes within 24 to 72 hours after birth Closure of the ductus may be delayed, or not occur at all in preterm infants Patent PDA causes pulmonary blood flow, pulmonary congestion, workload of the RV pulmonary venous return and workload of the RV

HemodynamicsLR shunt from aorta to PA Flow occurs both in systole & diastole as pressure gradient + throughout cardiac cycle b/t two arteries- continuous murmur Systolic as well as diastolic overloading of pul artery To lungs Lt atrium (enlarges) To normal mitral valve accentuated S1 ,mitral delayed diastolic murmur

To Lt ventricle during diastole diastolic overloading (LV enlarges)prolongation of Lt ventricle systoledelayed closure of aortic valve late A2

C/FDepend on size of the shunt and the degree of associated pulmonary hypertension Asymptomatic if small ductus Large ductus frequent lower RTIs CHF poor weight gain

Physical examinationTachycardia Exertional dyspnea Hyperactive precordium Bounding peripheral pulses with wide pulse pressure Systolic thrill at upper left sternal border

Physical findingsAuscultation: P2 normal or accentuated, Rough grade 1-4/6 continuous murmur machinery murmur at left infraclavicular or upper LSB which peaks at S2 and fades before the S1

Ductus arteriosus

Investigations:1.

CXR: N to cardiomegaly , increased pulmonary vascular markings

2. ECG: N or LVH , BVH in large shunts, RVH with development of pulmonary vascular obstructive disease 3. Echo: presence of PDA, size of cardiac chambers

Management:Medical: Indomethacin ineffective in term infants In preterm infants indomethacin is used (8090% success in infants > 1200 grams) nonsurgical closure Subacute bacterial endocarditis prophylaxis

Surgical closure: Surgical correction when the PDA is large except in patients with pulmonary vascular obstructive disease Transcatheter closure of small defects has become standard therapy

Natural history:Spontaneous closure unlikely in full term infants CHF & recurrent chest infections if large shunt Infective endocarditis Pulmonary vascular obstructive disease if PAH is untreated PDA aneurysm may develop, rarely

AV CanalIncludes:ASD VSD Abnormalities of the Mitral and/or Tricuspid valves

Greater incidence in children with Downs Syndrome

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