Cardiology Doctor in Sahakaranagar atrial septal defect This congenital condition may not be diagnosed until adult life. The asymptomatic patient with a small left to right shunt may require no treatment. The detection of right ventricular dilatation on echocardiography strongly suggests a significant shunt. A large shunt (pulmonary blood flow at least twice systemic) or an episode of paradoxical embolism is an indication for surgical or catheter-based closure. This should be performed because of the risk of right ventricular failure. Pulmonary hypertension is an uncommon complication of the condition in adults. If TOE shows the defect has a reasonable rim of surrounding tissue, it may be suitable for closure using a closure device. A number of these have been developed. The most commonly used is the Amplatzer occluder device, made of Nitonol steel mesh . It has two discs joined by an isthmus. The device is loaded into a catheter which is advanced over a guide