REGIONAL ambulance bosses are urging people to take cases of fainting seriously.

Yorkshire Ambulance Service says one in two people will faint at some point in their lives.

It adds that fainting can be caused by dehydration or low blood pressure, but may also be a sign of the heart rhythm disorder, arrhythmia.

The most common type of arrhythmia is a condition known as atrial fibrillation (AF), which puts people at increased risk of a stroke.

Dr Steven Dykes, deputy medical director at the ambulance service, issued advice to coincide with World Heart Rhythm Week.

"One of the best ways to monitor your heart rhythm is to check your pulse regularly," he said.

"A normal pulse is between 60 and 100 beats per minute, but there may be reasons why your pulse is faster or slower, such as caffeine, medication, stress or anxiety.

"If your pulse seems to be racing or slow for some or most of the time, or if it feels irregular, speak to your doctor – even if you don't feel unwell."

For more details, visit knowyourpulse.org.