Preclinical in vivo testing of the Arrow-Trerotola percutaneous thrombolytic device for venous thrombosis.
OBJECTIVE
To test the safety and efficacy of using the Arrow-Trerotola percutaneous thrombolytic device (PTD) for treating deep vein thrombosis (DVT) in an animal model.


METHODS
An established canine model of iliocaval subacute thrombosis was used. Thrombosis was caused by balloon occlusion of the infrarenal inferior vena cava (IVC) for 7 (n = 12), 10 (n = 1), or 17 (n = 1) days. Treatment was performed with use of an 8-F, over-the-wire (0.035-inch) PTD with a 15-mm-diameter basket. The procedure was performed without IVC filtration. Two acute procedures were performed and 12 procedures were intended as survival procedures with 30-day follow-up. Pulmonary arteriography, blood gases, and pulmonary artery pressure measurement were performed before and after the procedure, and at follow-up. The animals were killed after the follow-up procedure and their IVC, iliac veins, and lungs were removed and examined histologically. Heparin was used intraprocedurally but thrombolytic agents were not used. Low-molecular-weight heparin was given daily after the procedure.


RESULTS
Thrombolysis was completely (12 of 13) or partially (one of 13) successful in all animals in the 7- and 10-day groups, but was unsuccessful in the animal in the 17-day group (n = 1). Variable amounts of segmental and subsegmental pulmonary emboli were found in all animals with small increases in pulmonary artery pressure. Two animals died within 6 days of the procedure, possibly due to pulmonary emboli. At 30-day follow-up, IVC patency was preserved in 80% (eight of 10) of animals, but significant caval narrowing due to intimal hyperplasia was noted at follow-up. All pulmonary emboli had resolved angiographically at follow-up, but evidence of recanalized or resolving pulmonary thromboemboli was found in seven of the 12 surviving animals. No acute vascular injury (eg, perforation) occurred.


CONCLUSIONS
The modified PTD used in this study is effective in treating subacute (<7 days old) venous thrombosis, but temporary filtration will probably be necessary to keep pulmonary emboli to a minimum during the procedure. The 30-day patency is encouraging. The results in this animal model indicate that the Arrow-Trerotola PTD may be useful in the percutaneous treatment of DVT in humans.
Trerotola
S O
SO
Department of Radiology, Indiana University School of Medicine, Indianapolis, USA. streroto@iupui.edu
McLennan
G
G
Davidson
D
D
Lane
K A
KA
Ambrosius
W T
WT
Lazzaro
C
C
Dreesen
J
J
D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D005500:Follow-Up Studies; D011655:Pulmonary Embolism / Q000517:prevention & control; D015912:Thrombolytic Therapy / Q000295:instrumentation*; D020246:Venous Thrombosis / Q000628:therapy*