The Simon nitinol inferior vena cava filter: preliminary experience in the UK.

The Simon nitinol filter is one of a new range of inferior vena cava filters designed for percutaneous placement. It employs a thermal memory alloy allowing it to be introduced in a straight form via a 9F sheath when cool but transforming instantly into its predetermined filter shape at body temperature. It was placed rapidly and successfully in six patients via a femoral approach and one patient via an antecubital vein. The only complication was an asymptomatic IVC obstruction in one patient.