Microchip Can Measure Blood Pressure

Jan. 23, 2002 -- Having your heart checked in the future may be as easy as driving through a tollbooth.

Researchers are testing a small plastic chip designed to let doctors measure blood pressure within the heart as well as major arteries.

The device was originally developed for use in jet engines by Mark Allen at the Georgia Institute of Technology. Allen describes the technology as being similar to electronic toll-collection systems used on highways.

"The unique philosophy of this particular device is to try to keep what's inside the body as simple as possible and put all the complexity in the readout that's outside the body," said Allen.

Soon this microchip may be available to monitor blood pressure inside the heart, giving doctors valuable treatment information.

"It's going to essentially be like an early warning system in patients we know have significant problems," said Dr. Barry Katzen, medical director of the Miami Cardiac and Vascular Institute.

"If we can detect the higher pressure earlier then we can adjust the medication and hopefully keep the patient out of the hospital and feeling better," Dr. Michele Hamilton of the UCLA Medical Center told ABCNEWS' John McKenzie on World News Tonight.

Preliminary data using this new chip technology in animals was presented today at the International Symposium on Endovascular Therapy in Miami. Testing in humans is set to begin in May.

How It Works

A microchip, smaller than a dime and as thin as a piece of paper, is threaded through a blood vessel and secured within the heart or an artery, where it directly measures and then sends out the patient's blood pressure information.

"It could certainly be done on an outpatient basis in a fairly simple procedure with just a little local anesthesia," said Katzen.

This tiny piece of plastic is the equivalent of transponders used in cars for paying tolls automatically. Unlike the car transponder that sends the identity of the driver to the toll collector, this microchip sends the blood pressure in the patient to the doctor.

The equivalent of the toll booth is a small handheld transmitter/receiver that provides power to the microchip and records the blood-pressure readings from the embedded chip.

Potential Uses

Doctors are hoping to use the new technology in patients with aneurysms and congestive heart failure — two problems in which blood pressure is crucial.

When an aneurysm, or weakening ofn an artery, is detected, doctors insert a fabric graft that replaces the weakened area. In some cases the grafts leak and cause a local increase in pressure that can cause the artery to rupture.

By placing a microchip in the graft area, doctors will know if the pressure is reaching dangerous levels and the patient is at risk of rupturing an artery.

The chip also may help congestive heart failure patients who suffer serious problems when pressure in the heart is too high.

"Currently, physicians treating patients with congestive heart failure are forced to go by the patient's symptoms, or perform an invasive procedure to obtain information about the pressures in the heart," said Dr. Jay Yadav, director of vascular intervention for the department of cardiovascular medicine at the Cleveland Clinic.

In the future, this device may also be modified to measure other properties within the body, such as blood glucose levels in diabetic patients.