Injectable hydrogel electrodes open door to new painless treatment regimen for arrhythmia

Study lays foundation for revolutionary treatment regimen to treat ventricular arrhythmia. The research, published in Natural communicationsdemonstrates the design and feasibility of a new hydrogel-based stimulation modality.

The urgent need for an effective therapeutic regimen for ventricular arrhythmia inspired THI’s Electrophysiology Research and Clinical Innovations (EPCRI) team, led by its Director, Dr. Razavi, to partner with Dr. Cosgriff -Hernandez and his UT Austin Biomedical Engineering (UT Austin BME) to co-develop an innovative strategy that addresses the pathophysiology of reentrant arrhythmia.

Ventricular arrhythmia, which occurs in the lower chambers of the heart or ventricles, is the leading cause of sudden cardiac death in the United States. When a heart rhythm abnormality occurs in a self-perpetuating manner, it is called a reentrant arrhythmia, which is usually fatal.

“Re-entry occurs primarily because of a conduction delay in scarred heart tissue, usually after coronary artery occlusion during a heart attack, which can be corrected by allowing pacing in these regions,” a said Dr. Razavi, a practicing cardiologist and cardiac electrophysiologist. “These hydrogels can then access scar tissue, allowing direct stimulation of otherwise inaccessible regions of the heart.”

Considering the biostability, biocompatibility, tunable properties, and ease of incorporation of hydrogels, scientists are exploring them as potential electrodes that can be easily introduced into coronary veins. A clinical advantage of this unique system is that ischemia can be avoided by administering the hydrogel through the veins.

Researchers successfully deployed innovative hydrogel technology through minimally invasive catheter delivery in a porcine model.

“Hydrogels have significant conductive properties that allow simultaneous stimulation from multiple sites along the entire length of the hydrogel and create a conduction highway similar to those of Purkinje fibers,” according to Dr. Cosgriff-Hernandez.

Today, arrhythmia can be treated with medications and procedures to control irregular rhythms. Antiarrhythmic drugs currently available on the market are not always effective; although the drugs slow conduction velocity, they facilitate reentry arrhythmia. Additionally, these medications can be toxic and cause destruction of tissues near diseased areas of the heart. Even with widely used interventional ablation therapies, arrhythmia recurs in a significant proportion of patients. None of these procedures address the re-entry mechanism.

Cardiac defibrillators implanted to compensate for shortcomings in current treatment options are painful when delivering electric shocks to restore heart rhythm and can seriously deteriorate the patient’s quality of life. If left untreated, the arrhythmia can damage the heart, brain, or other organs, leading to a stroke or cardiac arrest, in which the heart suddenly and unexpectedly stops beating.

“When injected into the target vessels, the conductive hydrogel adapts to the morphology of the patient’s vessels. Adding a traditional pacemaker to this gel provides stimulation that resembles the heart’s native conduction, effectively mimicking the heart’s native electrical rhythm, and extinguishes the cause. for arrhythmia, providing painless defibrillation,” added Dr. Cosgriff-Hernandez.

The work demonstrates for the first time the ability to confer direct electrical stimulation to native and healed mid-myocardium using injectable hydrogel electrodes as a stimulation modality.

With delivery of a minimally invasive catheter and standard pacemaker technologies, this study indicates the feasibility of a new pacing modality that resembles native conduction, potentially eliminating fatal reentrant arrhythmia and providing painless defibrillation , which can be successfully adopted into a clinical workflow.

Scientific advances are important since pain management is very important for the overall well-being of patients with heart, lung and blood diseases. Such innovation in painless defibrillation and arrhythmia prevention could revolutionize heart rhythm management.

Provided by the Texas Heart Institute