[Determining the effectiveness of percutaneous cava filters: experimental studies].
OBJECTIVE
In vitro clot-trapping capacity of 16 different caval filters should be evaluated under varying experimental conditions.


METHODS
In a flow model simulating in vivo conditions (soft latex tube, dextran solution at 37 degrees C, pulsatile flow at a mean rate of 3 1/min) the efficiency of 16 caval filters was evaluated in horizontal and vertical position by using 640 or 1280 clots/filter (8 sizes). Non-self centering filters were tested in centric and in tilted position.


RESULTS
Efficiency of optimally centered caval filters varied between 97.8 and 69.4%. The largest thrombi were captured by all optimal centered filters. A change from vertical to horizontal position of the flow model resulted in a variation of filter efficiency by about 4.8%. Efficiency of non-self centering filters decreased significantly when placed in a tilted position (mean decrease 15.5%; range 2.7%-37.7%) resulting in a deterioration of the capture rate by as much as 43.2%.


CONCLUSIONS
Under optimal study conditions efficiency of all evaluated caval filters was high. Tilting of caval filters resulted in a significant efficiency decrease.
Neuerburg
J
J
Klinik für Radiologische Diagnostik des Klinikums, Medizinischen Fakultät, RWTH-Aachen.
Haupt-Pichler
A
A
Katterbach
F J
FJ
Eilers
R
R
Siess
T
T
Buro
K
K
von Pichler
C
C
Mottaghy
K
K
Günther
R W
RW
D000818:Animals; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D008955:Models, Cardiovascular; D011655:Pulmonary Embolism / Q000517:prevention & control; D011673:Pulsatile Flow; D013552:Swine; D016896:Treatment Outcome; D016306:Vena Cava Filters
Bestimmung der Effektivität perkutaner Kavafilter: Experimentelle Untersuchungen.