A PROMISING new approach for the treatment of heart-attack victims was unveiled Monday by scientists.
A ?sticking plaster? can help heal damaged hearts by providing a ?scaffold? for healthy cells to re-grow.
In fact, engineers at Brown University and in India say the new device has a promising new approach to treating heart-attack victims.
According to the study published in Acta Biomaterialia, the researchers created a nanopatch with carbon nanofibers and a polymer. In laboratory tests, natural heart-tissue cell density on the nanoscaffold was six times greater than the control sample, while neuron density had doubled.
In a heart attack, some parts of the muscle can be left dead, which increases the risk of a second or subsequent attack. The inch-long black patch, which is only as thick as a single human hair, is built of carbon and is intended to be stuck to the dead area and attract new cell growth to bring it back to life.
No tests have been conducted on live subjects yet but the researchers hope that the method will not only help in the immediate aftermath of a heart attack but could also be used for those who suffered years earlier.
The damage caused by heart attacks causes breathlessness and exhaustion and makes everyday tasks such as housework and dressing much harder.
The scientists turned to nanotechnology. In a lab, they built a scaffold-looking structure consisting of carbon nanofibers and a government-approved polymer. Tests showed the synthetic nanopatch regenerated natural heart tissue cells - called cardiomyocytes - as well as neurons. In short, the tests showed that a dead region of the heart can be brought back to life.
?This whole idea is to put something where dead tissue is to help regenerate it, so that you eventually have a healthy heart,? said David Stout, a graduate student in the School of Engineering at Brown and the lead author of the paper published in Acta Biomaterialia.
The approach, if successful, would help millions of people. In 2009, some 785,000 Americans suffered a new heart attack linked to weakness caused by the scarred cardiac muscle from a previous heart attack, according to the American Heart Association. Just as ominously, a third of women and a fifth of men who have experienced a heart attack will have another one within six years, the researchers added, citing the American Heart Association.
What is unique about the experiments at Brown and at the India Institute of Technology Kanpur is the engineers employed carbon nanofibers, helical-shaped tubes with diameters between 60 and 200 nanometers. The carbon nanofibers work well because they are excellent conductors of electrons, performing the kind of electrical connections the heart relies upon for keeping a steady beat. The researchers stitched the nanofibers together using a poly lactic-co-glycolic acid polymer to form a mesh about 22 millimeters long and 15 microns thick and resembling ?a black Band Aid,? Stout said. They laid the mesh on a glass substrate to test whether cardiomyocytes would colonize the surface and grow more cells.
In tests with the 200-nanometer-diameter carbon nanofibers seeded with cardiomyocytes, five times as many heart-tissue cells colonized the surface after four hours than with a control sample consisting of the polymer only. After five days, the density of the surface was six times greater than the control sample, the researchers reported. Neuron density had also doubled after four days, they added.
The scaffold works because it is elastic and durable, and can thus expand and contract much like heart tissue, said Thomas Webster, associate professor in engineering and orthopaedics at Brown and the corresponding author on the paper. It?s because of these properties and the carbon nanofibers that cardiomyocytes and neurons congregate on the scaffold and spawn new cells, in effect regenerating the area.
The scientists want to tweak the scaffold pattern to better mimic the electrical current of the heart, as well as build an in-vitro model to test how the material reacts to the heart?s voltage and beat regime. They also want to make sure the cardiomyocytes that grow on the scaffolds are endowed with the same abilities as other heart-tissue cells.
Thomas Webster, of Brown University, Rhode Island, which conducted the research, said: ?What we wanted to do was develop a material that could be inserted wherever the damage is, maybe through a catheter or small tube, so that new healthy tissue can grow on top of it.? It is likely to be 10 or 15 years before the plasters can be used on humans.
Previous studies have shown that when one suffers a heart attack, a part of the heart dies. Nerve cells in the heart?s wall and a special class of cells that spontaneously expand and contract ? keeping the heart beating in perfect synchronicity ? are lost forever. Surgeons cannot repair the affected area. It is as if when confronted with a road riddled with potholes, you abandon what?s there and build a new road instead
Needless to say, this is a grossly inefficient way to treat arguably the single most important organ in the human body. The best approach would be to figure out how to resuscitate the deadened area, and in this quest, a group of researchers at Brown University and in India might have an answer.
A heart attack is when blood vessels that supply blood to the heart are blocked, preventing enough oxygen from getting to the heart. The heart muscle dies or becomes permanently damaged.
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