A simple operation that fixes an irregular heartbeat slashes patients' risk of dementia by more than a third, according to new research. The procedure, called catheter ablation, uses radiofrequency to burn small areas of tissue causing faulty nerve messages.
A fine tube is inserted into a vein in the leg and threaded through vessels into the organ. Former prime minster Tony Blair underwent the procedure almost two decades ago.
Lead author Dr Bahadar Srichawla, of the University of Massachusetts in the US, said: "Previous studies have found people with arrythmias may have long-term thinking and memory problems due to how this condition may affect the blood flow to the brain. Our findings show that treatment with catheter ablation is linked to a reduced risk of cognitive impairment."
Known medically as AFib (atrial fibrillation), it is the most common heart disorder - affecting almost one million Britons. The study involved 887 mainly elderly patients - of whom 193 received catheter ablation. The latter group were 36 percent less prone to cognitive impairment than peers treated only with drugs.
Participants completed a thinking test at the outset - then one and two years later. Questions challenged short-term memory, attention, concentration and language. Scores ranged from zero to 30 - with cognitive impairment defined as 23 or less.
People who received catheter ablation had an average score of 25 compared to people who did not receive the procedure with an average score of 23.
Added Dr Srichawla: "Our results are encouraging. However there are many factors taken into consideration when catheter ablation is prescribed. More research is needed to confirm our results."
It is an effective but risky procedure. Up to one patient in ten can suffer complications including a stroke, perforation of the heart muscle or dangerously low blood pressure. Not all respond, even after multiple treatments and some are unable to have the operation due to frailty or due to previous operations on the heart.
AFib affects more than 46 million people globally. It occurs when the heart's two upper chambers go out of sync, causing an abnormal heart rhythm. This, in turn, affects how well blood flows to the lower chambers of the heart, called the ventricles.
Symptoms include palpitations, a fluttering feeling in the chest, extreme tiredness, dizziness and shortness of breath. AFib can happen at any age. However, it is more common among older adults.
There is currently no cure. But doctors can treat the condition with medications and surgical procedures as needed. Last month as study found Afib patinets are 13 percent more likely to develop dementia.
Dr Srichawla presented the study at an American Academy of Neurology meeting in Boston. A limitation was no tests of blood flow to the brain were recorded.
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