Journal of Ultrasound in Medicine, Vol 16, Issue 8 529-535, Copyright © 1997 by American Institute of Ultrasound in Medicine
Prototype therapeutic ultrasound emitting catheter for accelerating thrombolysis
K. Tachibana and S. Tachibana
First Department of Internal Medicine, Fukuoka University School of Medicine, Japan.
The aim of this study was to evaluate the performance of a new therapeutic
ultrasound device for accelerating thrombolysis by urokinase. Artificial
thrombi were produced in vitro by Chandler's loop method. Urokinase (240
IU) was added to the artificial thrombi (n = 5) before exposure to
ultrasound with the new catheter-delivered device. Ultrasound (1.3 MHz) was
applied with an intensity of 0.3 W/cm2 for 60 s. The degree of fibrinolysis
was obtained by measurement of thrombus weight and calculated as
percentages. Fibrinolysis was compared between control thrombus groups (n =
5) treated with urokinase alone or with ultrasound alone (analysis of
variance, P < 0.05). Ultrasound plus urokinase (33.1 +/- 6.1% [mean +/-
standard deviation]) was significantly different urokinase alone (12.3 +/-
2.4%) after 15 min of incubation. Ultrasound alone resulted in no
fibrinolysis (0.9 +/- 2.5%). Ultrasound energy from the catheter-based
device was sufficient to induce acceleration of fibrinolysis with
urokinase.
