The Harry M. Zweig Memorial Fund for Equine Research

En Bloc Removal of Intravascular Thrombi via an Extracorporeal Bypass Circuit in Experimentally Induced Jugular Thrombosis in Horses

Principal Investigator: Rolfe Radcliffe
Contact Information: Email:; Phone: 607-253-4414
Project Costs: $25,144
Project Period: 1/1/2015-12/31/2015

Radcliffe R.Our broad objectives are to improve and develop new jugular thrombosis treatment methods in horses. Our
specific aims are: 1. Validate an experimental model of jugular thrombosis in horses to facilitate the
development of new treatment modalities. 2. Test the AngioVac Cannula System in horses for treatment of
complete jugular thrombosis. Vascular thrombosis is a significant problem in horses, and effective treatments
are lacking. Treatment in humans has evolved rapidly over the past decade. Currently, local methods are
considered standard of care for catheter associated thrombosis in people; these techniques have the advantages
of reduced complications compared to systemic fibrinolytic drugs, shortened hospitalization times, and quicker
return to function. The AngioVac® Cannula System has shown great promise for the treatment of venous
thrombosis in people and will be directly applied to horses in this study.

A total of sixteen horses with experimentally induced left jugular vein thrombosis will be used for this project.
The experimental design will involve two parts: Part 1 will consist of eight horses (Control Group) for
verification of the thrombosis procedure and expected lack of thrombus resolution during a 30 day follow-up
period; Part 2 will consist of eight horses (Treatment Group) treated with mechanical thrombolysis using the
AngioVac® Cannula System at acute and subacute times post-thrombosis induction. Treatment horses will also
be monitored for 30 days post-treatment to document success rate, potential complications and limitations of
this procedure. First, we plan to purchase equipment and supplies, acquire horses and document normal jugular
vein structure and function during the early stage of the project. Second, we will induce jugular vein
thrombosis in 8 horses (Control Group) and monitor for 30 days to document complete thrombosis and lack of
resolution without treatment. Third, we will induce jugular vein thrombosis in an additional 8 horses
(Treatment Group) and follow with the AngioVac® Cannula System for en bloc removal of the jugular
thrombus. Lastly, we will compare the two groups using appropriate statistical analysis, interpret the findings
and begin manuscript preparation. Successful application of this system to horses will provide owners and
veterinarians with a cost-effective treatment for a common and potentially debilitating problem in horses.