Current indications for and results of Greenfield filter placement.

Review of the indications for and results of Greenfield filter placement for protection against thromboembolism in 260 patients shows that the most common indication remains a contraindication to anticoagulation therapy (35%) or recurrent thromboembolism in spite of anticoagulation therapy (31%). Prophylaxis in the absence of embolism is a less common indication (18%), but increasingly favorable experience by others with the filter in place of anticoagulation therapy in the elderly may alter the approach to these patients. Although two patients with massive embolism who had undergone pulmonary embolectomy died postoperatively, no deaths occurred as a result of filter placement. Only one of the remaining 35 patients who died (14%) within 2 weeks of filter placement had suspected recurrent embolism. Follow-up studies in 99 patients extending to 100 months showed only two early and no late occlusions of the filter, for a long-term patency rate of 98%. The recurrent embolism rate of 5% is comparable to that of previously reported experience and appears to be independent of the use of long-term anticoagulation therapy.