Uncontrolled blood pressure takes away the lives of about 7.1 million
worldwide every year. A systolic blood pressure above 140 millimetres of
mercury and a diastolic pressure above 90 mmHg brand a patient as hypertensive
and there are an estimated 1 billion people who have this degree of
hypertension in the world. Hypertension is managed primarily by the use of
'anti hypertensive drugs'. These drugs work by helping blood vessels to relax. Severe
hypertension may require three or more blood
pressure tablets. Drug therapy is
definitely superior over lifestyle modifications in aiding to attain optimum
Unfortunately 15 per cent of hypertensive patients do not respond to
anti-hypertensive drugs. A new technique of zapping a nerve with radio waves
has been found to be effective in controlling hypertension in patients
resistant to anti hypertensive drugs. Nerves surrounding the kidney are
targeted in this procedure. These nerves are housed within the wall of renal
artery and increase blood pressure by promoting salt and water retention, and
constricting blood vessels. Activation of renal sympathetic nerves is key to
pathogenesis of essential hypertension.
A probe is inserted through the patient's upper thigh and radio waves
are delivered to the inside of the renal artery. This heats up the artery by
10°C and the process literally switches off the nerves (activity of the nerve
is reduced by between 30 and 80 per cent. The artery is unarmed in the process.
The treatment brings down hypertension and would cut the risk of stroke and
heart disease. Researches haven't
found out any serious side-effects associated with this
modality of treatment.
The trial involved 106 patients with systolic blood pressure of more
160 mmHg and taking three or more anti-hypertensive drugs. Around half
experienced the procedure. The systolic blood pressure fell by at least 10 mmHg
in 84 per cent of those who received the treatment (after 6 months). The
results were published the leading medical journal Lancet.
Murray Esler of the Baker IDI Institute in
Melbourne, Australia, a leading member of the research team assures that renal sympathetic denervation will have a long lasting effect. This however requires
further discussion. The new modality of treatment should be available in Europe
and Australia within a year. However bigger trials and deeper dive in to long
term efficacy need to be performed.
believe the discovery could lead to a new approach to managing high blood