Double balloon dilation involves catheters inserted in the left and right femoral vessels placed parallel to stenotic lesions and inflated simultaneously. The two balloon technique creates a substantial decrease in pressure gradients by achieving greater dilation from the use of two smaller balloons as opposed to a single large balloon. Balloons are inflated and deflated repeatedly to reduce the resistance of the vessels to inflation. Once the balloons are removed an end-hole catheter is passed over the wires to ensure a moderate systemic pressure drop occurs and then a stent is placed. Substantial pressure drops are common following single balloon dilation procedures. Hydrophilic catheter treatments can also be used through placement of the catheter through the femoral veins to access the stenosis in the vena cava to measure haemodynamic and angiography. Angiography allows for visualisation of the stenosis in the vena cava and measurements of the pressures and length of narrowing can be obtained from the technique, including the narrowest diameter of the stenosis. Balloon angioplasties can also be performed in the narrowed vena cava using Sterling balloons. Dilations are also performed with higher pressure Dorado balloons, using the same wire as the Sterling balloon. Sustained results of increased flow and significant reduction in obstructions following stent implantation occurs from balloon angioplasty treatments. Epidemiology
Congenital stenosis of the vena cava is a rare congenital heart disease affecting 0.7 - 8.7% of the population. Vena cava anomalies are very rare and arise from incorrect development in the foetal heart.
Congenital stenosis of vena cava is a congenital anomaly in which the superior vena cava or inferior vena cava has an aberrant interruption or coarctation. In some cases, it can be asymptomatic, and in other cases it can lead to fluid accumulation and cardiopulmonary collapse. Symptoms and signs
Congenital heart defects may not show signs or symptoms until later stages of the childs life and have a delayed diagnosis. Congenital stenosis of the inferior vena cava is asymptomatic in many patients. Adolescent males with the condition have shown to presents with symptoms such as spontaneous lower extremity DVT, leg swelling, leg pain, varices in the lower extremities, hepatic thrombosis and hematochezia. Chylothorax has been observed rarely as a symptom of congenital stenosis of the superior vena cava in infant patients. Chylothorax results as a rare complication in which chyle leaks into the thoracic space following direct incidental damage and can also lead to increased thoracic duct pressure. Chylothorax leakage commonly occurs in patients with additional complex congenital heart lesions, increasing the risk of underlying vascular anomalies. Other symptoms which may become present later than adolescence includes venous hypertension, post necrotic hepatic cirrhosis and portal hypertension from the manifestation of the condition. Diagnosis
Congenital stenosis of the vena cava is a sub-classification of the overarching spectrum of congenital heart disease involving the vessels surrounding the heart resulting in disruption to normal cardiovascular blood flow. Diagnosis commonly occurs in early adolescence, expressed as symptoms such as deep vein thrombosis (DVT) occurring spontaneously.