Submitted by Dr T on November 10, 2010 – 11:49am
Atrial fibrillation (AF) is a major risk factor for stroke. AF remains a potent risk factor, accounting for approximately 15% of all thrombo-embolic strokes. Other factors such as hypertension, diabetes mellitus, congestive heart failure and prior stroke, all increase the risk of stroke in AF.
Currently, acetylsalicylic acid (Aspirin or ASA) and warfarin (Coumadin), are the only approved therapies for stroke prevention in patients with AF.
Although effective, Coumadin requires regular monitoring and dose adjustments. There are several new drugs that may be easier to use with a similar stroke risk reduction profile as Coumadin.
Dabigatran and another drug, Rivaroxaban, have been compared to Coumadin or other agents like Lovenox, which is an injectable blood thinner agent. Dabigatran, a new drug and a so-called oral “direct thrombin inhibitor” has just been released the US and may provide the first alternative to Coumadin.
Neither of these medications will need the frequent blood checks as we do for Coumadin, which is something that most patients will be excited about.
In a recent trial, Dabigatran reduced the risk of stroke/peripheral embolic events, by 34% (p<0.001) and the risk of hemorrhagic stroke by 74% (p<0.001) compared with warfarin (Coumadin).
Dabigatran has a rapid onset of action, with very few drug-drug interactions and patients don’t require any form of monitoring. It is soon to be released onto the market, but to my knowledge, at present limited to the treatment for patients with atrial fibrillation and their protection against stroke.
However, one of the drawbacks is that, unlike Coumadin, there is no easy way to reverse the effects of the blood thinning with either of these two, an issue that may be important after an injury or other causes of bleeding.