And the heart beats like a clock
Swiss scientists have developed a prototype of a heart rate driver working without batteries, which is based on a clock mechanism.
For the first time, the idea of using a mechanism that ensures the operation of a mechanical wristwatch to utilize the energy of heart contractions appeared in Professor Rolf Vogel of the University of Bern four years ago. The heart is a very promising source of energy, as it contracts 24 hours a day, 7 days a week. Moreover, the self-winding movement invented at the end of the XVIII century has demonstrated its exceptional reliability over the next few centuries.
The main component of the first heart rate driver prototype developed by Folegem and his colleagues is an ordinary wristwatch, from which all unnecessary parts were removed to reduce size and weight. In addition, the mechanism received a new housing with holes that allow it to be attached directly to the myocardium using suture material.
The device for obtaining the energy of heart contractions is sewn directly to the myocardium.
The principle of operation of such a rhythm driver is similar to the principle of operation of a wristwatch. Under the influence of external pressure, the eccentric of the clock mechanism begins to turn. This rotation progressively twists the mechanical spring. After complete twisting, the spring unwinds and rotates the electric microgenerator. Due to the constant movement, the spring is constantly in an almost wound-up state, ensuring the reliability of the current generator.
To test the prototype device, the researchers developed an electronic circuit that transforms and stores the signal using a small buffer capacity. This system was connected to a specially made rhythm driver. The system functioned in three stages. At the first stage, she received energy from the heart. At the second stage, the energy was temporarily stored in a buffer tank. After that, the stored energy was used by the rhythm driver to influence the heart muscle with weak electrical impulses.
The system has been successfully tested on domestic pigs. It made it possible to maintain an accelerated heartbeat with a reduction frequency of up to 130 beats per minute without using an external power source.
According to the authors, their development solves two main problems of traditional rhythm drivers. Firstly, the possibility of damage to the wires connecting them to the batteries poses a serious threat to the patient's life. Secondly, the lifetime of the batteries used is limited. The new system lacks the disadvantages described above, since the device for generating heart rate energy is placed directly on the myocardium.
The battery-free rhythm driver was tested by attaching an energy-collecting device to an electronic circuit that transforms and stores the signal using a small buffer tank. The stored energy was used to stimulate the heart muscle with a specially designed heart rate driver. Electrical stimuli were transmitted to the myocardium using epicardial wires.
The results of the work are presented at the annual Congress of the European Society of Cardiology in Barcelona.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on AlphaGalileo materials:
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01.09.2014