[In vitro bench tests of caval umbrella filters]

Seven ombrelles percutaneous cava filters, now available, are tested on hydraulic testing ground. Measurements are concerned with the blocking function of filters and pressure changes induced in the cava flow and the cava track wall of the testing ground. A statistical analysis of the results (100 measurements per filter) shows homogeneous reactions of each filter when faced with different situations imposed by variations of the testing ground. Greenfield's filter, a reference, is compared with other models. This one and the L.G. filter show satisfactory filtering qualities. Two other filters, Cardial and Vascor, offer a highest filtering power. Other models give poor filtering results.