Influence of thrombus age on the mechanical thrombectomy efficacy of the amplatz thrombectomy device in vitro.
OBJECTIVE
To determine the efficacy of thrombectomy for the Amplatz Thrombectomy Device (ATD) according to the age of the thrombus.


METHODS
Thrombectomy was performed with the 7 Fr or 8 Fr ATD. Five-day-old or 8-day-old thrombi were made from porcine blood by clotting within silicone tubes to be used in a flow model. Emboli sizes, weight, remaining thrombus and activation time were evaluated.


RESULTS
The age of the thrombus had no influence on the activation time necessary for complete thrombolysis. A significant difference was found in the overall amount of embolization only with the 7 Fr device although a similar trend was shown with the 8 Fr device. The amount of embolized thrombotic material was higher for both devices if older thrombi (i.e., 8 days old) were processed. The overall impression was that the 8 Fr device showed slightly better results (less remaining thrombus and embolization).


CONCLUSIONS
A tendency toward higher amounts of embolization was observed if older thrombi were used in the model. Therefore the interventional radiologist should be aware of the potentially higher risk of peripheral embolization when performing mechanical thrombectomy (with the ATD) in older thrombotic occlusions, especially since the higher rate of embolization was mainly due to an increased proportion of larger embolic particles (1 mm), which are clinically more significant.
Grimm
Jan
J
Klinik für Diagnostische Radiologie, Christian Albrechts Universität zu Kiel, A. Heller Strasse 9, 24105 Kiel, Germany. jgrimm@helix.mgh.harvard.edu
Jahnke
Thomas
T
Muhle
Claus
C
Heller
Martin
M
Müller-Hülsbeck
Stefan
S
D000818:Animals; D001157:Arterial Occlusive Diseases / Q000628:therapy*; D004195:Disease Models, Animal; D004617:Embolism / Q000209:etiology / Q000473:pathology; D004621:Embolization, Therapeutic / Q000295:instrumentation; D004867:Equipment Design; D005263:Femoral Artery / Q000473:pathology* / Q000601:surgery*; D008955:Models, Cardiovascular; D011183:Postoperative Complications / Q000209:etiology / Q000473:pathology; D013552:Swine; D017131:Thrombectomy / Q000295:instrumentation*; D013927:Thrombosis / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome