New technology to make heart monitoring easier

A recently developed wearable technology made from stretchy, lightweight material is capable of making heart monitoring easier and more accurate in comparison to existing electrocardiograph machines.

Developed by engineers, the latest incarnation of Lu's electronic tattoo technology, a graphene-based wearable device that can be placed on the skin to measure a variety of body responses, from electrical to biomechanical signals, reported the Journal of Advanced Science.

The device is so lightweight and stretchable that it can be placed over the heart for extended periods with little or no discomfort. It also measures cardiac health in two ways, taking electrocardiograph and seismocardiography readings simultaneously.

Most of us are familiar with the electrocardiogram (ECG), a method that records the rates of electrical activity produced each time the heart beats. Seismocardiography (SCG) is a measurement technique using chest vibrations associated with heartbeats.

Powered remotely by a smartphone, the e-tattoo is the first ultrathin and stretchable technology to measure both ECG and SCG.

"We can get much greater insight into heart health by the synchronous collection of data from both sources," said Lu, one of the researchers of the study.

ECG readings alone are not accurate enough for determining heart health, but they provide additional information when combined with SCG signal recordings. Like a form of quality control, the SCG indicates the accuracy of the ECG readings.

Although soft e-tattoos for ECG sensing are not new, other sensors, such as the SCG sensor, are still made from nonstretchable materials, making them bulky and uncomfortable to wear.

Lu and her team's e-tattoo are made of a piezoelectric polymer called polyvinylidene fluoride, capable of generating its own electric charge in response to mechanical stress. The device also includes 3D digital image correlation technology that is used to map chest vibrations in order to identify the best location on the chest to place the e-tattoo.

The e-tattoo has another advantage over traditional methods. Usually, an ECG measurement requires going into a doctor's office, where heart health can be monitored only for a couple of minutes at a time. This device can be worn for days, providing constant heart monitoring.