A magic net for weak hearts
A shrinking net wrapped around the heart will be able to replace artificial implants, and in many cases will allow the heart to rest and restore working capacity.
Artificial hearts or parts of them (usually carrying a heavy load and more often failing left ventricles) help hopeless patients waiting for a transplant. In patients with contraindications for heart transplantation (age, concomitant diseases, etc.), an artificial pump can be implanted as the final option.
Unfortunately, such a heart does not beat in an optimal rhythm, and, from whatever materials it is made, it can be rejected as a foreign object, and it is dangerous for the formation of blood clots due to the increased turbulence of the blood flow, damaging its cells. Therefore, patients with "steel hearts" are constantly forced to take drugs that suppress immunity and prevent thrombosis.
The idea to replace the prosthetic heart with an elastic contracting braid came to Peter Walker from the University of Leeds (Great Britain). An interfaculty group of engineers and cardiologists has produced a prototype of such a mesh.
The sensors built into it accurately determine the moment of the beginning of the contraction of the heart muscle and send a signal to micromotors that tighten the fibers, increasing the pressure in the ventricle and helping the heart to push out more blood, after which the network stretches again. The biocompatible polymer is not rejected by the body and does not come into contact with the bloodstream, which excludes the possibility of thrombosis.
"It's a very simple idea. Imagine a plastic bottle: if you squeeze it, the liquid level inside rises," says graduate student David Keeling, who designed an artificial heart to test and debug a prototype of the future "exoskeleton" for the heart.
Tests of the prototype of the invention on a mechanical simulator of the heart muscle developed by David, which beat in different modes, in combination with computer simulation of blood flow allowed the developers to improve the initial model.
Now they are selecting the optimal time and spatial parameters of the system. The next stage will be the selection of operating modes of the device for models of various heart diseases.
The possibilities of the invention are not limited to helping patients waiting for a transplant or serious heart surgery. It can significantly improve the quality of life of patients with various less severe diseases and even cure some of them.
Unfortunately, the advice "Rest, rest is the best medicine" is not suitable for the heart. But, as recent studies have shown, when using assistive devices, a temporary reduction in the load on the heart in many cases allows it to rest and restore efficiency. The device, developed by a group from Leeds, will be able to allow a tired heart, if not completely relax, then at least take some of the load off it.
Portal "Eternal youth" www.vechnayamolodost.ru based on the materials of the University of Leeds
20.02.2008