) أ.م.د. احمد عبداالمير دفار ( اختصاصي جراحة الصدر و القلب و االوعية الدموية
ATRIAL SEPTAL DEFECTS
Objective : To show the definition and management of ASD (Atrial
Septal Defects)
Atrial septal defect (ASD) is an opening in the atrial septum that enables mixing of
blood from the systemic and pulmonary venous circulations.
Pathophysiology
left-to-right shunting of blood across the defect and a marked increase in pulmonary
blood flow occurs.
The magnitude of the shunt across an ASD depends on the size of the defect.
Eisenmenger’s complex develops when the pulmonary vascular resistance becomes
highly elevated leading to reversal of shunting ( right to left )
Clinical Presentation
A great majority of patients with ASD are asymptomatic. Failure to thrive may be
observed. Occasional dyspnea on extreme exertion is observed. Recurrent respiratory
infection is not uncommon.
Auscultatory findings include a systolic flow (ejection systolic) murmur heard over the
pulmonary area in the 2nd or 3rd left intercostal & a fixed split S2.
Investigations
-Chest X-ray
It may be normal apart of plethoric lungs for small ASDs.
The pulmonary arteries may be enlarged with plethoric lungs & possibly
cardiomegaly if the presentation is late for large ASDs.
-Electrocardiogram
There are ECG findings
-Echocardiography
Echocardiography with color flow Doppler imaging is now the diagnostic modality
of choice.
-Cardiac catheterization
It's seldomly employed in the diagnosis of ASD
Treatment
Surgical intervention is indicated for large ASDs and for children with significant shunt
after 2 years of life (unusual for ASD to close after 2 years of age).
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