ABSTRACT
The earliest mechanical approaches to prevent pulmonary thromboembolism were associated with significant complications when the techniques were limited to direct operative approaches to the vena cava for ligation, placation or external clip application. When endovascular techniques were developed for vena caval filter placement more than 30 years ago, morbidity was reduced significantly, since venous access could be achieved under local anesthesia. But a more significant change occurred in the 1980s, when percutaneous sheaths and dilators converted the procedure from surgical to radiological. With this change, a variety of innovative filters emerged, characterized by relative ease of insertion and smaller profile to minimize the size of the sheath for introduction. The focus of complications had shifted from the procedure to the actual placement and performance of the filter. Unfortunately, most efforts in recent years have been to further reduce the profile of the carrier systems, so current publications found in the radiological journals have more to do with techniques and ease of insertion than evaluation of device performance over time. In fact, there is very little information about the long-term performance and complications of most of the vena caval filters used today.
