Upper extremity deep venous thrombosis. Underdiagnosed and potentially lethal.

The significance of upper extremity deep venous thrombosis (DVT) has been minimized in comparison to iliofemoral thrombosis, likely due to the erroneous belief that subsequent pulmonary thromboembolism is rare. The possibility of pulmonary thromboembolism originating in the upper extremity veins must now be seriously considered with catheters and medical instrumentation being performed more commonly in accessing the central venous system. It has been incorrectly assumed that the risk of pulmonary embolism was low due to the abundant collateral flow, and thus lack of stasis around an upper extremity even with venous occlusion. However, several studies, including a recent prospective trial, concluded that pulmonary embolism is not a rare complication in upper extremity DVT. Significantly, when comparing all sources of secondary upper extremity DVT, catheter-related upper extremity DVT is at greatest risk of subsequent pulmonary thromboembolism. We present an illustrative case documenting extensive pulmonary embolization that occurred following insertion of a central venous catheter and subsequent thrombosis of the right subclavian and innominate veins. With absolute contraindications to thrombolytic and anticoagulation therapy, prevention of further embolization was achieved by percutaneous insertion of a superior vena cava filter.