World's first implantable device to reduce high BP

London, May 9 (IANS) Not been able to control blood pressure even after gulping pills? Soon, an implantable device will reduce blood pressure by sending electrical signals to the brain.

In a first, German researchers have successfully reduced the blood pressure in rats by 40 percent with this device without any major side effects.

This could offer hope for a significant proportion of patients worldwide who do not respond to existing medical treatment for the condition.

"As the device will require surgery, it will come into play when patients, for whatever reasons, are resistant to medication," explained lead author Dennis Plachta from University of Freiburg, Germany.

The implantable device uses an intelligent circuit to record the activity of the patient, for instance when they are doing exercise, and adjust the blood pressure accordingly.

The device consists of 24 individual electrodes that are integrated into a micro-machined cuff.

It is designed to wrap around the vagal nerve, which extends from the brainstem to the thorax and abdomen - supplying and stimulating various major organs including the heart and major blood vessels.

The device works by picking up signals from specific sensors, known as baroreceptors, which are activated when blood vessels stretch.

These baroreceptors function to control short-term fluctuations in blood pressure.

No major side effects, such as a significant decrease in heart rate or breathing rate, occurred in rats when the electrode sites closest to the baroreceptor fibres were chosen for stimulation, said the study published in the Journal of Neural Engineering.

The device has been designed to identify only those fibres that influence the blood pressure and avoid those that are responsible for heart rate, the power of heart beat, ventilation and other vital functions, researchers added.

"It is possible to use the left vagal nerve to reduce blood pressure without any adverse side effects which is important for a wide variety of potential treatments that could utilise nerve stimulation without actually penetrating the nerve," Plachta noted.