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

Principal Investigator: Rolfe Radcliffe

Co-PI: Marjory Brooks

Department of Clinical Sciences
Sponsor: Harry M. Zweig Memorial Fund for Equine Research
Title: En Bloc Removal of Intravascular Thrombi via an Extracorporeal Bypass Circuit in Experimentally Induced Jugular Thrombosis in Horses
Project Amount: $10,000
Project Period: January 2014 to December 2014

DESCRIPTION (provided by applicant): 

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 AngioVacÒ 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 twelve 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 six 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 six horses (Treatment Group) treated with mechanical thrombolysis using the AngioVac® Cannula System at 24-30 hours 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 6 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 6 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.