While the clinical syndrome produced by obstruction of the superior vena cava may be quite disabling, it fortunately occurs with relative infrequency. Chronic mediastinal inflammation, malignant neoplasms, and aortic aneurysms appear to be the commonest causes of the obstruction. Although palliative efforts may be indicated in some cases of obstruction due to malignant tumor, the major therapeutic challenge concerns those cases in which the obstruction is due to benign, constrictive inflammatory changes in the mediastinum. The reported clinical experience with superior vena caval replacement or by-pass has been somewhat discouraging. Deterling and Bhonslay,2in 1955, reviewed their experimental studies and the published clinical experience with superior vena caval replacement and concluded that partial or complete failure of the graft was the most frequent result. It would appear, however, that autogenous tissue, especially autogenous venous tissue, should prove to be the most suitable material for superior vena caval grafting. It,