As Thin As Paper, the Blood Pressure Monitor That Fits INSIDE Your Artery

A BLOOD pressure monitoring device, smaller than a thumbnail and thinner than a sheet of paper, could be used to help thousands of heart patients.

The sensor, which folds up so it can be threaded through arteries, sits inside the body’s main artery, constantly monitoring pressure in the problem area.

At any one time there are around 700,000 people suffering with heart failure in the UK, and monitoring the blood pressure around their heart is essential because any change in pressure may indicate changes in the working of the heart which require treatment.

The device takes daily pressure readings of patients at home. The data is then transferred over a phone line. Doctors currently have no reliable, efficient way to measure this vital information.

‘Our EndoSensor enables doctors to monitor patients more closely and adjust medications as they see the disease progressing,’ says David Stern, chief executive of makers CardioMEMS.

‘Because the sensor detects a change in the body before any external symptoms are manifested, it serves as an early warning system and prevents patients from ending up in hospital.’ The device was initially designed for patients with abdominal aortic aneurysms – responsible for the deaths of one in every 100 men over 65 in Britain – but it is now also being looked at by U.S. researchers as a way of monitoring patients who have suffered heart failure.

An abdominal aortic aneurysm is a swelling of an area in the wall of the aorta, the body’s largest artery, which if left untreated can rupture with often fatal consequences. The swelling can cause pain in the chest or back, but the condition often goes unnoticed until it grows large enough to burst.

When that happens, blood rushes into the abdomen, causing searing pain and a sudden drop in blood pressure.

An increasing proportion of patients are successfully treated by inserting small fabric tubes inside the bulging arteries to support them, but there is always the risk of blood leaking and rupturing into the sac around the damaged area.

As a result, patients have to undergo lifelong routine testing to have the pressure around the aneurysm monitored.

But the new microchip device can be implanted into the sac around the aneurysm to provide early warning of pressure build-up. It has a miniature radio aerial which allows it to send out signals about pressure changes which are then recorded on a handheld device and can be transferred by phone to a doctor.

Around 100 patients have had the device implanted for abdominal aortic aneurysms, but thousands more could also benefit when the hoped-for approval for marketing comes through later this year.

So far, there is no information on when the devices could be in use in the UK, although approval in the UK and Europe usually follows American approval.