The U.S. Food and Drug Administration warned that patients with mechanical heart valves should not use a blood thinner named Pradaxa.
The FDA said a clinical trail in Europe called RE-ALIGN was stopped because patients taking Pradaxa -- otherwise known as dabigatran -- were more likely to suffer from strokes, heart attacks and clots forming on their mechanical heart valves compared to those taking an older medication called warfarin.
Dabigatran patients also bled more after valve surgery compared to those who took warfarin.
Patients who are taking the drug and have mechanical heart valves should immediately go to their doctor and talk about being switched to a different anticoagulant. They should not stop using the drug on their own, because it can cause other problems.
However, the FDA emphasized that it has not changed its recommendations about dabigatran, which is currently approved to treat patients with atrial fibrillation not caused by heart valve problems. It was never approved to treat patients with mechanical heart valves.
Patients with atrial fibrillation should not stop taking the medication unless they have consulted with their doctor. Though there were some bleeding issues in patients with atrial fibrillation that were reported -- including 50 deaths said to be caused by the drug -- the FDA reviewed the matter and said there was no additional bleeding risk associated with dabigatran. Stopping the use of the drug for these patients can increase the risk of stroke, which can lead to disability and death.
The FDA said there were no studies on the affects of dabigatran and patients with bioprosthetic valves so they could not make a recommendation on that front.