Fainting could be a sign of a fatal condition
Cardiology Fainting or palpitations may be signs of an underlying heart rhythm disorder that could potentially prove fatal. Here's how to check whether you are at risk.
Arrhythmia is common, unsuspected and potentially serious
Fainting or palpitations may be nothing to worry about, but they can also be early warnings of a potentially fatal condition. Both commonly occur in people with cardiac arrhythmias - the medical term for an irregular heart rhythm. Heart rhythm disorders are Britain’s biggest killer.
There are four main types of arrhythmias. They are common, potentially serious, and often unsuspected.
Fainting (syncope) resulting from an insufficient blood supply to the brain, can be a symptom of the most common arrhythmia - atrial fibrillation (AF), an irregular and/or too-rapid heart rhythm. This is means blood does not flow through the body properly, which may result in blood clots. If a clot forms in the heart and travels to the brain it can cause a potentially fatal AF-related stroke.
"AF causes 12,000 debilitating and fatal AF-related strokes in the UK each year. These are more debilitating and more likely to be fatal than most other strokes. Many could be avoided if AF is diagnosed and appropriate anticoagulation therapy prescribed," says Trudie C A Lobban MBE FRCP Edin, Founder and Chief Executive of the charities STARS, Arrhythmia Alliance and AF Association.
"AF affects one in four of us over the age of 40, and the symptoms are often palpitations or a faint, which are all too often overlooked," she adds. "Anyone of any age experiencing a faint could have an underlying arrhythmia, which could result in an AF-related stroke."
Aspirin proven ineffective in preventing AF-related strokes
Anticoagulants, which help prevent clots forming and therefore, reducing the risk of an AF-related stroke, have long been used to treat AF, but many people have AF unknowingly, and so suffer strokes that may have been avoided.
Lobban points out that aspirin, commonly taken as a stroke-preventative, has been proven ineffective in preventing AF-related strokes.
The good news is that a simple pulse check will indicate the possibility of AF before it results in a potentially fatal AF-related stroke. However, the UK currently has no national screening programme of pulse checks or heart rhythm screening, so you need to know how to do it yourself.
Lobban says: "Checking your pulse will indicate your heart rhythm as well as your heart rate - how often the heart beats - but also the regularity of the rhythm, which is important in diagnosing AF."
How to take your own pulse
To get your baseline pulse and normal heart rhythm, take your resting pulse when you wake in the morning and before bed, for seven days.
To assess your resting pulse rate in your wrist, sit down for five minutes beforehand. Remember that any stimulants (such as caffeine or nicotine) taken before the reading will affect the rate. You will need a watch or clock with a second hand.
Hold your left or right hand out with your palm facing up and your elbow slightly bent.
With your other hand, place your index and middle fingers on your wrist, at the base of your thumb. Your fingers should sit between the bone on the edge of your wrist and the stringy tendon attached to your thumb. You may need to move your fingers around to find the pulse. Keep firm pressure on your wrist with your fingers in order to feel your pulse.
Count for 30 seconds, and multiply by two to get your heart rate in beats per minute. If your heart rhythm is irregular, count for one minute and do not multiply.
Record the results. A heart rate of 60 to 100 beats a minute is normal, but also pay attention to the rhythm. If it is irregular - anything other than a steady boom, boom, boom - consult your doctor.
Everyone is different, so regular pulse checks will help you understand what is normal for you, and detect changes warranting investigation.
See KnowYourPulse for more details.
More information for healthcare practitioners
The Arythmia Allicance offers the STARS Blackout Checklist (recently updated) to help with diagnosis, resources for patients, and information about ECGs.