New Early Warning System for Sudden Cardiac Death
Researchers at Tomsk Polytechnic University have developed a nanosensor-based system that can detect early abnormalities in the function of cardiac muscle cells, which otherwise can be recorded only with invasive procedures.
The nanosensor-based hardware and software complex can measure cardiac micropotential energies without filtering and averaging-out cardiac cycles in real time. The device allows registering early abnormalities in the function of cardiac muscle cells, which otherwise can be recorded only during open-heart surgery or by inserting an electrode in a cardiac cavity through a vein. Such changes can lead to sudden cardiac death (SCD). Nowadays, there are no alternatives to the Tomsk device for a number of key characteristics in Russia and the world. ).
The main method of detection of electrical pulses in the heart is electrocardiography (ECG). Nevertheless, ECG modern devices detect already critical changes in the function of the myocardium.
“Therefore, there is much concern about the creation of devices for early detection of these disorders, when it is still possible to restore cell function using medication and without surgical intervention. To implement this, it is required to record cardiac micropotential energies, electrical pulses emitted by separate cells. Here, there is a question of how to implement it noninvasive. Our research team have worked on this task for a long time, as a consequence, we jointly with the participation of our colleagues, doctors, have developed a hardware and software complex.
“The core principles of its operation are similar to ECG, however, we changed sensors: we made nanosensors instead of conventional sensors and managed to measure signals of nanovoltage and microvoltage layers without filtering and averaging-out in broadband. The use of nanosensors led to the necessity to apply original circuit solutions, write individual software.
“Ultimately, we gained a tremendous difference in sensitivity,” Diana Avdeeva, Head of the TPU Laboratory for Medical Engineering, a research supervisor of the project, said.
The system consists of a set of sensors, a tiny key device for recording incoming signals from sensors and data processing software. The sensors are fixed on a patient’s chest using a conducting gel, and the monitoring procedure takes about 20 minutes.
Conventional ECG machines operate on frequencies from 0,05 Hz to 150 Hz, while the device of the Tomsk scientists operates on much higher frequencies of up to 10 000 Hz.
“Silver chloride electrodes are usually used for recording ECG of high quality. Our sensors are also silver chloride electrodes, however, we used silver nanoparticles. There are up to 16 thin plates from porous ceramics in every our sensor, silver nanoparticles are placed in these pores. There are millions of particles in one sensor, where every particle is a silver chloride electrode capable to enhance an electric field of the heart. Silver and gold nanoparticles are capable to enhance an electromagnetic field: visible light by 10,000 folds and infrared radiation by 20 folds. We also refused to use filters for rejection network interference and noises, which are usually used in conventional ECG and significantly distort micropotentials,” Diana Avdeeva said.
The published study includes the monitoring data of one volunteer’s heart function, who took part in the research for four years and was monitored every 7-10 days.
“At the beginning of our research, we recorded clear violations of activity of cardiac muscle cells. His attending physician recommended surgery, he gained an inserted stent at the Cardiology Research Institute. Then, he continued to take part in the research and the device recorded the further gradual restoration of cardiac function,” the scientist noted.
“A task to create a sensitive, tiny and affordable complex was set up, in order in a long run, outpatient clinics and patients at home could use it. Moreover, the developed methods and devices can be used not only in cardiology.
“The fields of any electrophysiological research, such as electroencephalography, electromyography and so on are promising. Of course, before applying it to cardiology, we have to pass some essential stages. These are the collection of the required array of statistics, certification of the complex for medical use. All these stages require sponsorship, we are engaged in searching for partners and supporting programs,” said research team member Mikhail Yuzhakov, Engineer at the TPU Laboratory for Medical Engineering.
Source: Tomsk Polytechnic University
