Indian boffins have developed a Bluetooth heart monitor that will send a text message to the nearest hospital if the wearer is about to have a heart attack.

The device analyses electrical signals from the heart to produce an electrocardiogram (ECG) and can send an SMS alert with the information.

The Wearable Cardiac Telemedicine System, developed by Thulasi Bai and S K Srivatsa of the Sathyabama University in Tamil Nadu, should offer renewed mobility to post-cardiac patients.

The prototype system periodically records an ECG and transmits the information via radio frequency signals to the patient's mobile phone.

This modified phone has an analyser circuit that checks the ECG signal for signs of imminent cardiac failure.

If errant signals are detected, such as any arrhythmia, the phone alerts the patient and transmits a sample of the ECG signal to the nearest medical care centre via SMS.

The device could give patients who have already had a heart attack a much greater chance of receiving life-saving treatment, the researchers claim.

"Our Wearable Cardiac Telemedicine System can help patients to regain their independence and return to an active social life or work schedule," said Bai.

The researchers are now working on how to enable GPS in the modified phone so that the medical centre can more quickly pinpoint the patient in the event of an attack.

They also hope to improve the level of detail that can be sent from the mobile phone to the emergency room using MMS rather than SMS.

The findings were reported in Inderscience's International Journal of Electronic Healthcare today.