Ever felt an odd flutter in your chest, as if your heart has suddenly squeezed in an extra beat? Most of us have at least one of these ‘ectopic’ beats a day, although we often don’t notice them. But if you have Atrial Fibrillation (AF), electrical impulses cause the upper chambers of your heart to beat in a chaotic way, and often so fast that the heart isn’t able to relax between contractions. It can mean that you’re left feeling tired, dizzy and short of breath. On the other hand you may not notice that anything’s wrong, until someone takes your pulse.
The more serious problem with AF, which affects around 10 percent of those over 75, is that it can increase the risk of a blood clot forming inside your heart. That clot can travel from the heart to the brain, leading to a stroke. AF can increase your risk of having a stroke by up to five times.
Whether you have a high, medium or low risk of having a stroke depends on a number of factors. These include your age, previous strokes or blood clots, high blood pressure and heart disease. If you have AF one of your doctor’s main concerns will be to reduce your risk of having a stroke.
Warfarin is the medication usually prescribed for most people with high to medium risk of stroke. It’s an anticoagulant, so it works by making your blood less likely to clot. Warfarin is effective, but it does have disadvantages. If you are on this drug, you have to go for repeat blood tests to check that your blood hasn’t become too thin. You also have to be very careful about what you eat and drink, as this can affect your blood. Some people who take warfarin find these restriction limit their ability to have a normal life.
NICE (the National Institute for Health and Clinical Excellence) has now approved a new drug, dabigatran (Pradaxa), as an option for the prevention of stroke and systemic embolism (a blockage in a blood vessel, caused, for instance, by a blood clot). However dabigatran hasn’t been recommended for everyone with AF. To be considered for this new treatment you have to fit a number of different criteria, including having nonvalvular AF, and being 65 or older, with one of the following conditions: diabetes mellitus, coronary artery disease or high blood pressure. NICE has recommended this new drug because “on balance, the benefits outweigh the risks, and it is seen as a cost-effective use of resources.”
What are the benefits? AF patients who take dabigatran don’t have to undergo the rigorous monitoring and repeat blood testing that comes with taking warfarin. And in trials, taking 150mg of dabigatran, twice daily, resulted in lower incidence of stroke and related conditions in clinical trials. So is it a clear-cut winner?
“Warfarin has been very important, and has been shown to substantially reduce your risk of stroke,” says Joe Korner, spokesperson for The Stroke Association. “But the problem is that it’s quite a difficult drug to administer, and people need to be monitored very regularly because if you have too much it can turn the problem of clotting into the problem of a bleed, and haemorrhage. That means that GPs are sometimes reluctant to prescribe it. That’s what we’ve had until now, and too often AF is left untreated.
“What’s important about Pradaxa is that it gives GPs another option, a different way of preventing blood clots. It’s not going to be a magic bullet, it isn’t going to replace warfarin, and there are some people for whom it may not be a better alternative. But the actual existence of an alternative treatment is really good. It means that people who can’t tolerate warfarin or who the GP is worried about may be able to get treatment.
“The other thing to bear in mind is that it’s a more expensive drug, (£2.52 a day per patient, compared to £1 a day for warfarin) so that’s an issue for the NHS. But the fact that NICE has approved it is an indication that the benefits of Pradaxa are worthwhile to the NHS.”
Saga Magazine’s Dr David Roche had this to say about the new drug, “dabigatran does the same job as warfarin, without some of its risks and the need for blood tests. It does, however, have some problems of its own. Unlike warfarin it cannot be reversed if you take too much.”