Use of a temporary caval filter in a young man with pulmonary embolism to prevent migration of massive caval thrombus during an attempt of caval thrombolysis.

A 33 year old male with no known risk factors for hypercoagulability developed a massive thrombi in the inferior vena cava (IVC). The patient had a history of both pulmonary embolism and embolism related syncope. The thrombus which extended proximally to the level of the renal vein and distally to the left superficial femoral vein did not respond to anticoagulant therapy or thrombolysis. Thirteen days after admission, we decided to use a temporary caval filter to provide protection from migration of the thrombus while attempting invasive thrombolytic therapy, which was performed using a tissue type plasminogen activator through a coaxial catheter of the temporary filter. This resulted in a marked decrease in the size of the thrombus, and multiple thrombi were found to be trapped in the temporary filter. Although the temporary caval filter was effective in capturing emboli, resulting in a decrease in the thrombus size, the thrombus was not completely dissolved within two weeks, which is the maximal implantation time. A permanent filter was eventually used to prevent pulmonary embolism, which could arise from the remaining thrombus. We have found placement of a temporary caval filter to be a safe and effective adjunct, in select cases, when attempting thrombolysis of massive thrombi in the IVC. Since we inserted the temporary filter 13 days after admission, use of a temporary filter during thrombolysis may have been more effective if conducted earlier in our patient's clinical course.