超音波による血管閉塞予防法開発のための基礎的検討

抄録

Background: Reocclusion occurred after various recanalization therapies. In particular, reocclusion was frequently observed immediately after the recombinant tissue-type plasminogen activator (rt-PA) treatment. This is a fatal problem, because anticoagulant therapy is prohibited within 24 hours after the rt-PA treatment. We report the thrombus growth control effect of non-invasive ultrasound (US) in an in vitro clot growth model.
Method: A clot was prepared by incubation of citrated human plasma, CaCl₂ solution and thrombin at 37°C for 60 min in a latex tube. After incubation, the latex tube was filled with degassed citrated human plasma. The plasma around the clot was irradiated with US in a water bath at 37°C. The US irradiation condition was: transducer size 10 mm, frequency 500 kHz, continuous wave, average intensity 0.32 W/cm², 30 min. To evaluate the thrombus growth control effect, the clot’s weight was measured before and after US irradiation.
Results: The clot’s increased weight was significantly suppressed in the US group compared with the Non-US group (58.3 mg vs. 107.7 mg, p<0.0025).
Conclusions: In this study, we showed that the non-invasive US could control the growth of thrombus. This safe and simple US method may be used to prevent the reocclusion after recanalization therapy.