Ultra-thin "e-tattoo" uses two sensors for better monitoring of the heart
We've already heard about flexible so-called "electronic tattoos," which are a more comfortable and longer-wearing alternative to the rigid electrodes traditionally used to monitor cardiac patients' hearts. A new one is claimed to be more accurate than others, however, as it tracks heart health in two ways.
The device was developed by a team from The University of Texas at Austin, led by Assoc. Prof. Nanshu Lu.
It incorporates two thin-film sensors, one made of gold and polyethylene terephthalate (PET) plastic, and one made of a polymer known as polyvinylidene fluoride (PVDF) – the latter is piezoelectric, meaning that it produces an electrical charge when subjected to mechanical stress. Both sensors are attached to a thin sheet of transparent 3M Tegaderm medical dressing.
Temporarily adhered to a patient's chest over their heart, the e-tattoo stretches with their skin as they move. This means that it causes them no discomfort, and it can remain in place for days at a time. The device currently has to be hard-wired to a computer, but down the road it may be able to wirelessly transmit data to an app on a nearby smartphone.
And, as mentioned, the e-tattoo performs dual functions, simultaneously utilizing its two sensors to monitor the heart via both electrocardiography (ECG) and seismocardiography (SCG).
ECG, which most people are familiar with, involves recording the electrical activity that is produced with each heartbeat. SCG, on the other hand, measures the chest vibrations that accompany the beating of the heart. According to the university, SCG serves as a form of quality control, indicating the accuracy of ECG readings.
"We can get much greater insight into heart health by the synchronous collection of data from both sources," says Lu.
The research is described in a paper – the lead author of which is Dr. Taewoo Ha – which was recently published in the journal Advanced Science.