An evolution in protocols regarding indications and modalities for Partial Interruption of the Inferior Vena Cava (PIIVC) on 621 patients at Grenoble University Hospital is reported and the influence of new methods in diagnosis (vascular sonography) and therapy (percutaneous filters) is assessed. This comparative study covers the intervals from 1982-1984 (Period A - 333 patients), and 1989-1991 (Period B - 288 patients). The percentage of patients with venous thromboembolic disease who underwent PIIVC clearly decreased (21.8% in period A vs. 13% in period B, p < 0.01). The incidence of what are currently miscalled "prophylactic", but are in fact adjunctive indications also diminished (115 patients in period A, or 34.5% of the PIIVC cases vs. 60 patients in period B, or 20.8% of the PIIVC cases, p < 0.05). There was a reduction in the use of Miles caval clips (59 patients or 17.7% for period A vs. 34 patients or 11.8% for period B, p < 0.05). Although there has been an increase in the use of percutaneous caval filters, the use of percutaneous filters has not lead to an increase in the real rate of PIIVC performed by an Angiology Unit with a large experience in the diagnosis and follow-up of patients with venous thromboembolic disease.