2. • ASD isan acyanotic CHD characterized by defect
in theinteratrial septum
• Causing aleft to right flow between theatria
• Severity dependson :
- sizeof defect
- sizeof shunt
- associated anomalies
• Resulting in spectrum from :
- asymptomatic to
- right sided overload, pulm. Art. HTN, and even
atrial arrhythmias
3. • ASD represents10% of all CHD ( emed )
• 3 common types
- Ostium secundum ( 75% )
- Ostium Primum ( 15 – 20% )
- Sinusvenosus( 5 – 10% )
4.
5. • Male: female= 1:2
• Most infant and children areasymptomatic,
but thisagain dependson severity of defect
• Symptomsaremoreprevalent aspatient ages,
usually around ageof 40
6. • Magnitudeof L – R shunt dependson :
- Defect size
- Complianceof ventricles
- Relativeresistancein both pulmonary and
systemic circulation
• Shunting occursduring latevent systoleand
early diastole
7. • Thevolumeoverload isusually well tolerated
in children
• Even though thepulmonary flow may bemore
than twice
• However if left untreated… reversal of shunt
can eventually occur at alater age.
9. Signs
• Widefixed split of S2 ( mostly seen in largedefects)
• S1 may besplit with thesecond component being
increased in intensity dueto delayed tricuspid closureand
forceful contraction of right ventricle
• ESM - increaseright sided flow ( 2nd
IC spaceat upper left
sternal border )
• Largedefectsmay haverumbling MDM at lower left
sternal border ( increaseflow acrosstricuspid)
11. ECG
Enlarged ‘p’
wave
indicating
Right atrial
hypertrophy
rSR’ seen and tall R wave
Indicating RBBB and
RVH
Also notethat theaVF is
predominantly upwardsas
compared to Lead I
indicating Right Axis
Deviation
LAD with rSR’ in V1 issuggestive
of Ostium primum defect
12. Echocardiography
• Main diagnostic investigation
• Transthoracic 2D echocardiography especially subcostal view
isvery helpful
• Transesophageal Echo used for sinusvenosusdefect
• Doppler echo isused to demonstratetheflow acrossthe
septum
13. MRI
• Can beuseto identify sizeand location of defect
• A major advantageof MRI istheability to quantify
right ventricular size, volume, and function along
with theability to identify thesystemic and
pulmonary venousreturn.
14. Treatment
• No medical treatment
• Surgical
- Median sternotomy with direct closureof small to
moderatedefect
- Larger defectsclosed with autologouspericardium or
syntethic patcheslikepolyester polymer
( Dacron )or polytetrafluoroethylene( PTFE )
15. • Minimally invasivetechniqueswith hemisternotomy
and limited thoracotomy isto improvecosmetic
outcome
• PercutaneousTranscatheter Closure
- viafemoral vein
- successisasgood as96% in good hands
