Enhancement of Thrombolytic Therapy by Transcutaneous Ultrasound and Perfluorocarbon Exposed Sonicated Dextrose Albumin in Thrombotic Arterial Occlusion

Background and Objectives：Perfluorocarbon exposed sonicated dextrose albumin (PESDA) microbubbles has been suggested to facilitate thrombus disruption under the transcutaneous ultrasound (US). Thus, we investigated whether such a noninvasive approach could augment thrombolytic effect of fibrinolytic agent in an experimental thrombotic model. Materials and Methods：Thrombus formation was induced with electrical injury in the rabbit iliofemoral arteries (n＝20)；Thrombus occlusion was documented by angiography in all arteries. In the control group, only tissue plasminogen activator (t-PA, 3 mg/kg) was administered intravenously in five rabbits. In the Group 1 (n＝9), injured arteries were exposed to transcutaneous US (20 kHz, 30 W/cm 2, continuous mode) with t-PA (3 mg/kg). In the Group 2 (n＝6), the same treatment was given while admini-stering PESDA continuously (10 ml/min, intravenous). Angiographic results were evaluated at 10 minute interval for 1 hour respectively. Results：In the control group, two of five iliofemoral arteries (40.0%) were recanalized and one of nine iliofemoral arteries (11.1%) was recanalized in Group 1. In contrast, four of six iliofemoral arteries (66.7%) were recanalized angiographically in Group 2 (p＝0.392 vs. control group；p＝ 0.047 vs. Group 1). However, late reocclusion occurred in all iliofemoral arteries of Group 2. Conclusion： Although PESDA with transcutaneous US significantly enhanced initial angiographic patency rate of t-PA, it wa