Earbuds that spot a dicky heartbeat
HIGH-TECH wireless earbuds could detect hidden heart problems while you listen to music or chat on the phone. the buds resemble those used by millions of smartphone users — they work like headphones to play sounds into the ear and have a miniature microphone for speech. But they are also packed with high-tech sensors which can pick up tiny vibrations generated by the heart as it beats.
These vibrations, which pass through blood vessels, bones and muscles around the ear canal, cannot be heard by the human ear, but can be recorded by the sensors (which must be used as much as possible).
The data is wirelessly transmitted to a microchip in a hand-held device, which analyses it for clues that might indicate a heart disorder. The results can then be relayed to the patient and doctor’s smartphones.
Tests on the earbuds show they can detect atrial fibrillation, an abnormal heart rhythm. Around 1.2 million people in the UK have been diagnosed with it, but thousands more are thought to have it without realising as, apart from the odd slight ‘fluttering’ in the chest, there are often no symptoms.
In most cases, the heart beats extremely fast — 150 beats per minute (BPM) or more, compared with a normal resting pulse of 60 to 100 bpm for an adult. Less commonly, heart rate in some sufferers can drop to below 60 bpm.
As the heart is beating irregularly, blood may accumulate and clot inside the chambers of the heart.
The risk is that these clots can travel to the blood vessels that feed the brain, leading to a stroke. Atrial fibrillation causes 16,000 strokes a year in england alone.
TREATMENTS include bloodthinning drugs to stop clots forming, as well as cardioversion, where the heart is shocked back into normal rhythm.
But even diagnosing an abnormal heart rhythm in the first place can be problematic, as it may come and go. A holter monitor — a bulky box connected to electrodes that track the heart’s electrical activity — can be worn for up to 48 hours, but it is uncomfortable and provides limited information.
Recently, ‘wearable’ tech such as the Apple Watch has helped with diagnosis. this shines green light through the skin to measure the volume of blood passing through the wrist, and then converts this into a heart rate.
However, most of these devices only check heart rate every five minutes or so. in comparison, the earbuds, which are being developed by U.s. firm MindMics Inc, record heartbeat vibrations once a second. the frequency and strength of these vibrations increase or fall sharply when atrial fibrillation is affecting the heart.
A study by researchers from MindMics and the scripps research institute in La Jolla, california, published last December in the journal NPJ Digital medicine, compared the earbuds with an electrocardiogram (ECG).
In an ECG, electrodes are placed on the chest to track heart rhythm. it is the gold standard for checking for atrial fibrillation, but needs to be done by a doctor or nurse. When doctors tested the earbuds on 15 patients with atrial fibrillation and 25 healthy volunteers, the earbuds were just as accurate as an ECG.
The first earbuds are expected to become available in the U.S. later this year, and the UK after that.
Francisco Leyva-Leon, a professor of cardiology at Aston University, and consultant cardiologist at Queen elizabeth hospital, both in Birmingham, said: ‘It is plausible that these earbuds can pick up atrial fibrillation. But they need full clinical validation and are a long way from everyday use.’