New thrombolytic brush catheter in thrombosed polytetrafluoroethylene dialysis grafts: preclinical animal study.
OBJECTIVE
To assess the safety, efficacy, endothelial changes, and risks of pulmonary embolic events after the use of a new thrombolytic brush catheter in mature thrombosed polytetrafluoroethylene (PTFE) dialysis grafts in an animal model.


METHODS
Loop configuration PTFE grafts were implanted in the femoral vessels of 12 canines 4 weeks before mechanical thrombosis was performed. The thrombus was allowed to consolidate for 24 hours in 10 animals, 72 hours in one animal, and 7 days in one animal. Standard percutaneous criss-cross catheter access was performed, and a soft, low-speed, brush (6 mm in diameter), aided by 250,000 U of periprocedural urokinase, was utilized for thrombolysis. The native vessels, just distal to the anastomosis, and lungs were evaluated macro- and microscopically.


RESULTS
Thrombolysis was complete in all grafts with the exception of a small segment between the crossing of the access vascular sheaths. The total thrombolysis time ranged from 8 to 12 minutes; this included 5 minutes of pulse-spray lacing. No difference in thrombolysis time was found with regard to the age or amount of thrombus. Minimal endothelial changes were noted and no evidence of acute pulmonary embolus was found on necropsy or histologic studies.


CONCLUSIONS
This method offers a simple, safe, and efficient means of recanalization of thrombosed PTFE dialysis grafts in this canine model.
Castañeda
F
F
Department of Radiology, University of Illinois College of Medicine at Peoria, 61605, USA.
Wyffels
P L
PL
Patel
J C
JC
Swischuk
J L
JL
Li
R
R
Cole
B A
BA
Cragg
A H
AH
D000818:Animals; D001807:Blood Vessel Prosthesis; D002404:Catheterization / Q000295:instrumentation; D004285:Dogs; D004867:Equipment Design; D006083:Graft Occlusion, Vascular / Q000188:drug therapy*; D010960:Plasminogen Activators / Q000008:administration & dosage; D011138:Polytetrafluoroethylene; D006435:Renal Dialysis; D015912:Thrombolytic Therapy / Q000295:instrumentation* / Q000379:methods; D013927:Thrombosis / Q000188:drug therapy*; D013997:Time Factors; D014568:Urokinase-Type Plasminogen Activator / Q000008:administration & dosage
D011138:Polytetrafluoroethylene; D010960:Plasminogen Activators; D014568:Urokinase-Type Plasminogen Activator