The LGM Vena-Tech caval filter: Results of a multicenter study

Caval filters have proved essential to the prog-ess being made in the prevention of recurrent pulmonary embolism. A prospective multicenter study was conducted to evaluate the efficacy and possible complications relating to the LGM Vena-Tech percutaneous caval filter, which has been used in Europe since 1989. A total of 222 patients who had undergone LGM Vena-Tech filter placement between September 1989 and December 1991 were included in this study. Two hundred twenty caval filters were positioned via the percutaneous route: 154 of them via the jugular or subclavian vein and 66 via the femoral vein. Two filters could not be implanted. The in-hospital mortality rate was 1.7% (four patients), which included one patient who died of intraoperative recurrent pulmonary embolism. Mean follow-up was 15 months. Forty-one patients died during follow-up (actuarial survival 65.4% +/- 6% at 30 months). There were five cases of recurrent pulmonary embolism (cumulative freedom from pulmonary embolism 93.2% +/- 3.8% at 30 months). Ten patients had thrombosis of the inferior vena cava (actuarial caval patency 94% +/- 3.6% at 30 months). Eight filters (3.6%) migrated over distances that were less than the height of one vertebra. Shifting did not lead to any cases of thrombosis or recurrent pulmonary embolism. Ten filters tilted between 15 and 25 degrees in relation to the inferior vena cava axis. Recurrent pulmonary embolism never occurred concurrently with filter tilting. The LGM Vena-Tech caval filter ensures satisfactory prevention of pulmonary embolism with a low rate of complications. However, because its long-term fate is not known, its use should be restricted to cases in which heparin treatment has failed or is contraindicated.