Extracranial internal carotid artery dissection can cause ischemic stroke by thrombus formation or thromboembolism and subsequent arterial occlusion.  In fact, it is the 2nd most common etiology of strokes in patients younger than 45 years.  Traditionally, anticoagulant or antiplatelet agents have been administered to prevent ischemic insults, but does increased bleeding risk outweigh the benefits of these agents?

In 2010, the Cochrane Reviews determined there were no randomized controlled trials comparing either anticoagulants or antiplatelets to the control of no therapy.  Therefore there is no evidence supporting the routine use of antithrombotic agents in the treatment of extracranial internal carotid artery dissection.  There were also no randomized controlled trials comparing anticoagulants to antiplatelets, but the studies that did exist showed no significant difference between the two agents.

Currently underway is a large study that will hopefully shed some light on this controversy.

Lyrer P, Engelter S. Antithrombotic drugs for carotid artery dissection. Cochrane Database Syst Rev. 2010 Oct 6;(10):CD000255. doi: 10.1002/14651858.CD000255.pub2. Review.

Lyrer PA. Extracranial arterial dissection: anticoagulation is the treatment of choice: against. Stroke. 2005 Sep;36(9):2042-3. Epub 2005 Aug 18.

Stevic I, Chan HH, Chan AK. Carotid artery dissections: thrombosis of the false lumen. Thromb Res. 2011 Oct;128(4):317-24.