A recent study led by researchers at theTexas Heart Institute (THI) suggested sewing the flexible fibers composed of carbon nanotubes directly into the injured tissue to help restore the electrical function of the heart. These thin, flexible biocompatible fibers aid in building damaged heart tissues thus re-imposing electrical conduction of the heart and stabilizing its beating.
A lead author of the study Dr. Mehdi Razavi, a cardiologist by profession, said; “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,”.
Mr. Mehdi also serves as the director of Electrophysiology Clinical Research and Innovations at the Texas Heart Institute.
“Today there is no technology that treats the underlying cause of the No. 1 cause of sudden death, ventricular arrhythmias,” Razavi explained. “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.”
The invention of forming flexible conductive fibers using carbon nanotubes by Pasquali’s lab in 2013 lead to this research. The thin threadlike fibers first invented were a quarter of the width of human hair, surprisingly containing tens of millions of microscopic nanotubes. Studies are being conducted to learn the association of the fibers with the brain’s electrical conduction, to aid in cochlear implants, automotive and aerospace.
The findings of the study showed that the fibers are capable of conduction with or without a pacemaker. The biocompatible, polymer-coated fibers effectively restore conduction during month-long tests in large preclinical models as well as rodents, they act as electrodes as the ends are stripped.
The nanofibers are effective in restoring conduction whether the initial conduction was slowed, severed or blocked. However, in the case of rodents with the removal of the nanofibers, conduction disappears.
An assistant professor of clinical medicine at the University of Illinois College of Medicine, Mark McCauley, the co-lead author said; “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,”. Mark is a postdoctoral fellow at the Texas Heart Institute and conducted numerous experiments for the study.
Razavi said, “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.”
Pasquali said many uncertainties remained before the procedure was applied to human testing. There is a need to invent sewing of fibers with a minimally invasive catheter, considering the strength of the fibers to be strong as well as flexible enough to serve a constantly beating heart for a long duration. Studies must determine the length and width of the fibers, and correspondingly the electrical conduction it can conduct.
Pasquali said; “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.”
“Good interfacial contact is also critical to pick up and deliver the electrical signal. 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 of coatings.” Pasquali explained.
Razavi said that antiarrhythmic drugs contraindicate myocardial infarction patients, he said; “What is really needed therapeutically is to increase conduction,” he explained. “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.”
This research will shape the future of cardiac treatment and may save millions of lives in the time to come.