Textiles Help Monitor Vital Signs and Sleep Patterns

A new design project aims to empower citizens to fight cardiovascular diseases by preventive lifestyle and early diagnosis.

The MyHeart consortium, comprising 33 industrial, research, academic, and medical organizations from 10 different European countries, is working on both the preventative and management aspects of chronic cardiovascular disease. It is doing so through the application of technology that has been designed to monitor vital body signs (VBS), and software that can be programmed to analyze the measured data in relation to heart function and provide direct feedback to users or clinicians. The principal technology development common to all of these applications has been the development of on-body sensors and electronics for monitoring VBS and physical movement.

The starting point of the project is continuous monitoring of VBS with intelligent biomedical textiles, with integrated electronics and sensors and on-body processing systems. Examples of such textiles include an electrically conducting pillowcase that makes contact with the user's head, and a similar sheet of material at the foot of the bed that contacts the user's feet. These two electrodes pick up the minute electrical potential developed between the head and the feet as a result of the electrical impulses of the heart. An additional sensor, made from a sheet of pressure sensitive electret material, is positioned halfway up the bed under the mattress cover to detect user movement. This sensor is also sensitive enough to pick up the chest movements associated with breathing and can even detect the ballistic recoil generated by contraction of the user's heart muscles.

Combined with information from the movement sensor, these measurements are then used to identify periods of light, deep, and REM (Rapid Eye Movement) sleep, micro-arousals and waking periods. Each morning, after downloading the information to a computer, the user can access a detailed breakdown of their sleep patterns in the form of parameters such as time of going to bed, time awake in bed, time asleep, and sleep efficiency. The system even gives users clues as to why their sleep was interrupted – for example, by periods of snoring.

Another example of the technology is a textile vest that features electrodes integrated into the cloth that are suitable for recording an electrocardiogram (ECG) and chest impedance test, which help to calculate a new parameter called heart frequency variability.

"This new parameter that is of considerable interest in the monitoring of heart failure patients,” said MyHeart researcher Christian Zugck, M.D., of the department of internal medicine at Heidelberg University (Germany). "In some patients, at least, it might help to detect critical episodes far earlier than conventional parameters like body weight. This would lead to fewer hospital admissions.”

Related Links:
MyHeart consortium
Heidelberg University