
Illustration by James Philpot/Texas Heart Institute
Texas Heart doctors confirm Rice-made, conductive carbon threads are electrical bridges
Thin, flexible fibers made of carbon nanotubes have now proven able to bridge damaged heart tissues and deliver the electrical signals needed to keep those hearts beating.
Scientists at Texas Heart Institute (THI) report they have used biocompatible fibers invented at Rice University in studies that showed sewing them directly into damaged tissue can restore electrical function to hearts.
“Instead of shocking and defibrillating, we are actually correcting diseased conduction of the largest major pumping chamber of the heart by creating a bridge to bypass and conduct over a scarred area of a damaged heart,” said Dr. Mehdi Razavi, a cardiologist and director of Electrophysiology Clinical Research and Innovations at THI, who co-led the study with Rice chemical and biomolecular engineer Matteo Pasquali.
“Today there is no technology that treats the underlying cause of the No. 1 cause of sudden death, ventricular arrhythmias,” Razavi said. “These arrhythmias are caused by the disorganized firing of impulses from the heart’s lower chambers and are challenging to treat in patients after a heart attack or with scarred heart tissue due to such other conditions as congestive heart failure or dilated cardiomyopathy.”
Results of the studies on preclinical models appear as an open-access Editor’s Pick in the American Heart Association’s Circulation: Arrhythmia and Electrophysiology. The association helped fund the research with a 2015 grant.
The research springs from the pioneering 2013 invention by Pasquali’s lab of a method to make conductive fibers out of carbon nanotubes. The lab’s first threadlike fibers were a quarter of the width of a human hair, but contained tens of millions of microscopic nanotubes. The fibers are also being studied for electrical interfaces with the brain, for use in cochlear implants, as flexible antennas and for automotive and aerospace applications.
The experiments showed the nontoxic, polymer-coated fibers, with their ends stripped to serve as electrodes, were effective in restoring function during monthlong tests in large preclinical models as well as rodents, whether the initial conduction was slowed, severed or blocked, according to the researchers. The fibers served their purpose with or without the presence of a pacemaker, they found.
In the rodents, they wrote, conduction disappeared when the fibers were removed.
“The reestablishment of cardiac conduction with carbon nanotube fibers has the potential to revolutionize therapy for cardiac electrical disturbances, one of the most common causes of death in the United States,” said co-lead author Mark McCauley, who carried out many of the experiments as a postdoctoral fellow at THI. He is now an assistant professor of clinical medicine at the University of Illinois College of Medicine.
“Our experiments provided the first scientific support for using a synthetic material-based treatment rather than a drug to treat the leading cause of sudden death in the U.S. and many developing countries around the world,” Razavi added.
Many questions remain before the procedure can move toward human testing, Pasquali said. The researchers must establish a way to sew the fibers in place using a minimally invasive catheter, and make sure the fibers are strong and flexible enough to serve a constantly beating heart over the long term. He said they must also determine how long and wide fibers should be, precisely how much electricity they need to carry and how they would perform in the growing hearts of young patients.
“Flexibility is important because the heart is continuously pulsating and moving, so anything that’s attached to the heart’s surface is going to be deformed and flexed,” said Pasquali, who has appointments at Rice’s Brown School of Engineering and Wiess School of Natural Sciences.
“Good interfacial contact is also critical to pick up and deliver the electrical signal,” he said. “In the past, multiple materials had to be combined to attain both electrical conductivity and effective contacts. These fibers have both properties built in by design, which greatly simplifies device construction and lowers risks of long-term failure due to delamination of multiple layers or coatings.”
Razavi noted that while there are many effective antiarrhythmic drugs available, they are often contraindicated in patients after a heart attack. “What is really needed therapeutically is to increase conduction,” he said. “Carbon nanotube fibers have the conductive properties of metal but are flexible enough to allow us to navigate and deliver energy to a very specific area of a delicate, damaged heart.”
Learn more: Damaged hearts rewired with nanotube fibers
The Latest on: Carbon nanotube fibers
No news articles
via Google News
The Latest on: Carbon nanotube fibers
- U.S. Marines are Testing 5G Technology on Military Baseson January 14, 2021 at 1:19 am
Fast-moving drones, equipped with adaptable sensors and a massively increased ability to receive, transmit and process information, can move supplies, perform higher-risk missions beyond at perimeter ...
- Conductive Silicone Makes Flexible Circuitson January 9, 2021 at 3:59 pm
[Andrew Quitmeyer] has been researching flexible circuits for a while now, and recently stumbled upon an expired patent for flexible ignition cables, using carbon fibers mixed with a conductive ...
- Silk Material Eyed for Flexible Electronicson January 6, 2021 at 4:01 pm
“It is made of natural fibers that humans have been using for thousands of ... which also works extensively on carbon nanotubes (CNTs), decided to examine the molecular interactions between nanotubes ...
- 3D Printing High-Strength Carbon Composites Using PEEK, PAEKon January 6, 2021 at 4:01 pm
Bheda says Arevo Labs' team has optimized matrix polymer formulations reinforced with carbon fiber and carbon nanotubes, along with inventing some extrusion technology to make the polymers suitable ...
- NIOSH Science Blog Reports on Recent Article Concerning Carbon Nanotubes and Nanofibers Used or Produced in U.S. Facilitieson January 4, 2021 at 4:00 pm
On January 5, 2021, the National Institute for Occupational Safety and Health (NIOSH) posted a Science Blog item entitled “Understanding the Broad Class of Carbon Nanotubes and Nanofibers (CNT/F ...
- Carbon nanotubes toughen up thermoset compositeson December 21, 2020 at 4:00 pm
They embedded tiny “forests” of carbon nanotubes within a glue-like polymer matrix, then pressed the matrix between layers of carbon fiber composites. The nanotubes, resembling tiny, ...
- New Polymers and Nanotubes Add Muscle to Prosthetic Limbson December 20, 2020 at 4:01 pm
The application of an electrical charge to single-walled carbon nanotubes produces a direct conversion of electrical energy to mechanical energy through a material response. In the late 1940s, Israeli ...
- Smart fabric collects space dust on International Space Stationon December 16, 2020 at 4:00 pm
An Army-funded smart fiber being tested on the International Space Station could be used to develop space dust telescopes and allow astronauts to feel through their pressurized suits. Researchers ...
- Hair Styling with Physicson December 15, 2020 at 4:00 pm
Sameh Tawfick and his teammates came across a strange occurrence a few years ago while studying how carbon nanotubes self-assemble in liquid ... a series of experiments on micrometer-thick carbon ...
- Carbon Nanotube News and Researchon December 4, 2020 at 4:00 pm
it becomes much more difficult. Thin, flexible fibers made of carbon nanotubes have now proven able to bridge damaged heart tissues and deliver the electrical signals needed to keep those hearts ...
via Bing News