Acute Pericardial Effusion during Endovascular Intervention for Superior Vena Cava Syndrome: Case Series and Review.

We describe three cases of acute pericardial effusion during endovascular treatment of superior vena cava (SVC) syndrome, one of which resulted in fatal pericardial tamponade. SVC syndrome results from impaired venous return from the head and upper extremities to the right atrium. Malignancy and catheter-induced SVC stenosis accounts for the majority of cases of SVC syndrome. Endovascular therapy is the treatment of choice for SVC syndrome due to its rapid relief of symptoms and low morbidity. Acute pericardial effusion and pericardial tamponade may result from inadvertent extraluminal traversal of the SVC in the so-called danger zone above the right atrium, as well as secondary to dissection of wires in a location where fascial planes have been altered by neoplasia or inflammation.