COMPARATIVE STUDY ON FATIGUE STRENGTH OF 8 KINDS OF VENA CAVA FILTERS UNDER TWO WORKING CONDITIONS

In order to explore the reasons of fatigue failure of vena cava filters, it is necessary to study the fatigue strength of the filter under cyclic variable loads. SolidWorks software was used to build models of 8 filters, ABAQUS software was used to analyze the fatigue strength of 8 filters under circumferential pulsating cyclic load and radial compression cyclic load, and the safety of one filter was verified by experiments. In the circumferential fatigue analysis, all the alternating strain points of 8 filters are below the fatigue limit curve, and the safety factors are greater than 1, which meet the fatigue life requirements. In the radial fatigue analysis, some alternating strain points of the new filter and the TrapEase filter are above the fatigue limit curve, and the safety factors are less than 1. The other 6 filters meet the fatigue life requirements. The recyclable filter may not meet the requirement of fatigue life of 10 years and can be used as a temporary filter. Through 14 days, 21 days and 28 days of animal experiments, three small sweetgum pigs were implanted with Aegisy filter. The safety of Aegisy filter is comprehensively evaluated. The results show a good reference for the design, development and clinical application of vena cava filters.