OBSTRUCTION OF THE SUPERIOR VENA CAVA: A REVIEW OF THE LITERATURE AND REPORT OF TWO PERSONAL CASES

Abstract
The first authentic case was reported by William Hunter in 1757. A critical review of the literature discloses 250 authentic cases from 1904 through 1945, 145 verified by autopsy or surgery. A bibliography of literature since 1904 is presented. Bibliographic data are tabulated according to etiology. Comparisons are made with Fisher''s collection of 252 cases prior to 1904 and composite figures presented covering total incidence of important etiological factors in 502 cases from world''s literature through 1945. Trends in etiology since 1904, as regards various types of chronic fibrous mediastinitis, show a drop in incidence of syphilitic mediastinitis from 28.6% to 0.9%. During the same period tuberculous mediastinitis dropped from 11.4% to 5.4%. After 1922 the incidence of idiopathic or non-specific chronic fibrous mediastinitis increased from 5% to 11.7%. Trauma and acute respiratory tract infections are emphasized as frequent causes of idiopathic or non-specific chronic fibrous mediastinitis. Available literature indicates that 75 to 80% of cases of superior vana caval obstruction are due to chronic mediastinitis, malignant primary thoracic tumors, and aneurysms. Considerable evidence is presented indicating that obstruction of the superior vena cava is not uncommon. Applied anatomy of superior vena caval obstruction is presented with particular emphasis of the 4 principal collateral circulatory routes and the mediastinal lymphatic system. The collateral circulatory systems are defined and presented in one composite schematic representation. Two case reports of superior vena caval obstruction from idiopathic or nonspecific chronic fibrous mediastinitis are presented. In one the point of obstruction is below the azygos opening of the superior vena cava, proving this location of the obstruction to be compatible with life, contrary to exptl. observations of Carlson. The principal collateral system involved at this point of obstruction was shown to be the azygos.