IN-VITRO MODEL FOR THE EVALUATION OF INFERIOR VENA-CAVA FILTERS - EFFECT OF EXPERIMENTAL PARAMETERS ON THROMBUS-CAPTURING EFFICACY OF THE VENA TECH-LGM FILTER

PURPOSE: To determine the experimental parameters in an in vitro model that influence the thrombus-capturing efficacy of the Vena Tech-LGM f ilter. MATERIALS AND METHODS: The Vena Tech-LGM filter was evaluated i n an in vitro model of the vena cava with a computer-controlled flow s ystem with a total of 5,200 thrombi, The influences of the following e xperimental parameters on the capture rate were analyzed with a multip le logistic regression model: type of testing (single, double, and mul tiple shot testing), thrombus diameter and length, IVC diameter and or ientation, flow quality and quantity, flow velocity, and the length of the prepositioned thrombus. RESULTS: A significant influence on the c apture rate could be demonstrated for the type of testing, the thrombu s diameter and length, the IVC diameter, and with double shot testing for the length of the prepositioned thrombus and the IVC orientation, The flow quality and the peak velocity were not significant, Based on these results, a protocol for in vitro testing of IVC filters was desi gned. CONCLUSIONS: Experimental parameters influence the thrombus-capt uring efficacy of the Vena Tech-LGM fiber and should be taken into acc ount when in vitro testing is performed.