Scientists at the University of Glasgow are investigating how our ‘fight or flight’ mode plays a part in causing an abnormal heart rhythm, called atrial fibrillation, which markedly increases the risk of having a stroke.‌‌‌

Thanks to a £150,000 grant from the British Heart Foundation (BHF), Dr Antony Workman and his team are carrying out research into adrenaline and its role in Atrial Fibrillation (AF).
AF is a rapid, irregular beating of the heart’s upper chambers, the atria. It’s the most common type of irregular heart rhythm and is a major cause of stroke.

Normally, the heart’s natural pacemaker sends out a regular electrical impulse that travels through the heart. But when someone has AF, impulses can fire off from different places in the atria, causing chaotic electrical activity, which makes them have an irregular, and sometimes fast, pulse.

Around 92,000 people in Scotland have been diagnosed with AF but it’s estimated that there are thousands more living with undiagnosed AF. Stroke causes 4,300 deaths in Scotland each year, around 8% of all deaths.

Dr Workman explains: “The hormone adrenaline, part of our ‘fight-or-flight’ response, can cause AF if its levels are abnormally high in the atria. This can be found in people with heart failure for example.

“Adrenaline binds to numerous different types of receptors -adrenoceptors (AR) whose activation may disturb a variety of electrical currents and calcium movements in atrial cells. However, which AR-‘subtype’ causes which type of disturbance is unclear.

“Therefore, we’re studying single atrial cells, obtained from patients undergoing cardiac surgery, to identify which AR-subtypes can be blocked, either alone or together, to produce potentially beneficial effects such as stopping the spontaneous electrical activations or calcium movements that cause extra beats.

“This will improve our understanding of how adrenaline can cause AF, and may lead in the future to more effective AR-blockers for treating AF.”

Dr Shannon Amoils, Senior Research Adviser at the BHF, said: “This BHF-funded research by Dr Workman and his team will improve our understanding of how adrenaline can cause AF.

“This could lead to progress in understanding how to treat AF, and hence ultimately how to prevent its most devastating complication - stroke.

“It’s only because of the public’s generosity that we are able to continue investing in high quality research that has the potential to save lives.”


 

First published: 13 September 2016