Superior vena cava thrombosis and pulmonary embolus. Association with right atrial mural thrombus.

This is the first case report to our knowledge of superior vena cava syndrome and lethal, massive pulmonary embolus associated with a noniatrogenic right atrial mural thrombus. In situ, superior vena cava thrombosis was demonstrated by technetium Tc 99m nucleotide mediastinal flow scan and superior vena cava venography. Necropsy confirmed in situ superior vena cava thrombosis as well as trichamber mural thrombi and a massive pulmonary embolus. Intravenous streptokinase therapy for superior vena cava thrombosis was unsuccessful.