atrial septal defect
DESCRIPTION
short and simpleTRANSCRIPT
Atrial Septal Defect
Arvin Raj061303507Group B2
• ASD is an acyanotic CHD characterized by defect in the interatrial septum
• Causing a left to right flow between the atria
• Severity depends on : - size of defect - size of shunt - associated anomalies• Resulting in spectrum from : - asymptomatic to - right sided overload, pulm. Art. HTN, and
even atrial arrhythmias
• ASD represents 10% of all CHD ( emed )
• 3 common types
- Ostium secundum ( 75% )
- Ostium Primum ( 15 – 20% )
- Sinus venosus ( 5 – 10% )
• Male : female = 1:2
• Most infant and children are
asymptomatic, but this again depends on
severity of defect
• Symptoms are more prevalent as patient
ages, usually around age of 40
• Magnitude of L – R shunt depends on :
- Defect size
- Compliance of ventricles
- Relative resistance in both pulmonary
and
systemic circulation
• Shunting occurs during late vent systole
and early diastole
• The volume overload is usually well
tolerated in children
• Even though the pulmonary flow may
be more than twice
• However if left untreated… reversal
of shunt can eventually occur at a
later age.
Presentation
Symptoms• Often asymptomatic• Easy fatigability• Recurrent chest infection• Exertional dyspnoea• Palpitations related to arryhthmias
Signs
• Wide fixed split of S2 ( mostly seen in large
defects )
• S1 may be split with the second component being
increased in intensity due to delayed tricuspid
closure and forceful contraction of right ventricle
• ESM - increase right sided flow ( 2nd IC space at
upper left sternal border )
• Large defects may have rumbling MDM at lower
left sternal border ( increase flow across tricuspid)
CXR
Enlarged pulmonary arteries and increased vascular markings
Enlarged right atrium along with dilatation of right ventricle
ECG
Enlarged ‘p’ wave indicating Right atrial hypertrophy
rSR’ seen and tall R waveIndicating RBBB and RVH
Also note that the aVF is predominantly upwards as compared to Lead I indicating Right Axis Deviation
LAD with rSR’ in V1 is suggestive of Ostium primum defect
Echocardiography
• Main diagnostic investigation
• Transthoracic 2D echocardiography especially
subcostal view is very helpful
• Transesophageal Echo used for sinus venosus defect
• Doppler echo is used to demonstrate the flow across
the septum
MRI
• Can be use to identify size and location of
defect
• A major advantage of MRI is the ability to
quantify right ventricular size, volume, and
function along with the ability to identify
the systemic and pulmonary venous
return.
Treatment
• No medical treatment
• Surgical
- Median sternotomy with direct closure of
small to moderate defect
- Larger defects closed with autologous
pericardium or syntethic patches like
polyester polymer
( Dacron )or polytetrafluoroethylene ( PTFE )
• Minimally invasive techniques with
hemisternotomy and limited thoracotomy
is to improve cosmetic outcome
• Percutaneous Transcatheter Closure
- via femoral vein
- success is as good as 96% in good hands