New research casts doubt over heart disease treatments

High blood pressure is sometimes treated by calcium channel blockers to reduce the heart beat, as the channels – which allow calcium into the cells – are linked to muscle contraction. But the channels are also fundamental to the electrical currents which create the heartbeat.

University of Leeds scientists Dr Matthew Lancaster and Dr Sandra Jones have discovered that the channels gradually fail as we age and this failure is a likely factor in arrythmia and heart attacks in the elderly. By blocking the channels to treat high blood pressure, clinicians may unwittingly be increasing the likelihood of other problems developing.

Dr Lancaster said: “Many people suffer from an irregular heartbeat as they grow older and large numbers have pacemakers fitted. Making the link between these heart problems and the failure of the calcium channels as we age has flagged up a warning sign that some common medical treatments may be making the condition worse. Clinicians should think carefully before prescribing calcium channel blockers and ensure that, in treating one heart condition, they aren’t exacerbating others.”

The beating of the heart is caused by an electrical signal, which starts at the top of the heart in the sinoatrial (SA) node and is transmitted down to cause consecutive muscle contraction of the different chambers. The electrical signal is generated through an influx of calcium into the cells in the SA node, causing a change in voltage which creates the current.

Calcium enters the cells through channels – so these are fundamental to a steady heart beat. If the calcium channels are reduced, the heartbeat becomes irregular leading to a fall in blood pressure, fainting, and potentially, if untreated, death. These are the symptoms which can mean a patient needs a cardiac pacemaker fitted – but they may be exacerbated by treatment for high blood pressure which blocks the calcium channels.

The link between age and loss of calcium channels opens up new possibilities of treating heart conditions. Dr Jones said: “It may be possible to mitigate the effects of the loss of calcium channels through gene therapy, as the treatment would only be required in one specific area – the sinoatrial node – so should be fairly easy to administer.”

The researchers also think exercise may also be a factor. As members of the sports science group in Leeds’ Faculty of Biological Sciences, Drs Lancaster and Jones are now looking at whether exercise training is able to reduce the loss of the calcium channels in the SA node.

The research is published this week in the journal of the American Heart Association, Circulation.

Media Contact

Abigail Chard alfa

More Information:

http://www.fbs.leeds.ac.uk

All latest news from the category: Life Sciences and Chemistry

Articles and reports from the Life Sciences and chemistry area deal with applied and basic research into modern biology, chemistry and human medicine.

Valuable information can be found on a range of life sciences fields including bacteriology, biochemistry, bionics, bioinformatics, biophysics, biotechnology, genetics, geobotany, human biology, marine biology, microbiology, molecular biology, cellular biology, zoology, bioinorganic chemistry, microchemistry and environmental chemistry.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors