A team of researchers guided by investigators at Beth Israel Deaconess Medical Center (BIDMC) and Seoul National University have created a novel electric mesh device. This device is designed to be wrapped around the heart to convey electrical impulses such that cardiac function can be enhanced in trial models of heart failure. Heart failure is a key public health issue, which leads to mortality and disability in certain cases.
The details of the research have been published in the June 22, 2016 issue of Science Translational Medicine. It focuses on a probable new method for enhancing heart function and treating risky arrhythmias by enabling living heart muscle to function highly efficiently and compensating for damaged cardiac muscle.
In regular circumstances, the heart pumps blood all through the body via a sequence of coordinated contractions sustained by a meticulously synchronized electrical conduction system. Heart failure is triggered when weakened heart muscle affects the pumping mechanism of the heart and also results in the electrical conduction system to be damaged.
Some patients with heart failure are treated with resynchronization therapy, in which three small electrodes are implanted through a pacemaker to keep the heart contracting coordinately. But pacemakers deliver electrical stimulation only at specific places in the heart and do not provide comprehensive coverage of the entire organ, as the heart's own cardiac electrical conduction system does.
Hye Jin Hwang, MD, PhD, a researcher in the Division of Cardiovascular Medicine in BIDMC's CardioVascular Institute
"We knew that an integrated strategic approach that directly suppresses ventricular tachyarrhythmia in addition to improving cardiac function would be a promising strategy for the treatment of heart failure, ventricular arrhythmias, and sudden death," said coauthor Mark E. Josephson, MD, Chairman Emeritus of Cardiovascular Medicine at BIDMC, Distinguished Herman Dana Professor of Medicine at Harvard Medical School, and an international leader in the field of electrophysiology.
The innovative mesh consists of nanowires fixed into a rubber polymer that can conform to the distinctive 3D anatomy of an individual human heart. The mesh is made to literally "hug" the heart by wrapping around it, thus conveying electrical impulses to the entire heart muscle or ventricular myocardium.
The unique material for this device was developed by Hwang in partnership with researchers Taeghwan Hyeon, PhD, a specialist in nanomaterials and Dae-Hyeong Kim, PhD, a specialist in stretchable devices from Seoul National University.
We wanted to closely imitate cardiac tissue, which is very elastic, and also imitate its unique functions, which are highly conductive.
Hwang and her colleagues collaborated with multidisciplinary research teams from seven institutes spread across three countries - the U.S., Republic of Korea and China. Together they developed the unique nanomaterial, built an elastic electrical device, customized the device via 3D printing, performed pre-evaluation of mechanics using computer simulation and conducted operational appraisal of the device in an in vivo heart failure model.
When the mesh was tested on laboratory rats, the mesh blended electrically and structurally with the myocardium subsequent to a heart attack, serving as a substructure of the heart during cardiac movement and enhancing cardiac contractile operation without unsettling relaxation.
The big advance here has been finding a way to create a device that more accurately mimics normal physiology. The concept of wrapping the heart is not new, but doing it with this attention to a more physiologic approach makes the device exceptionally smart. This is not just another mechanical assist device. It's an innovative physiologic approach and provides an opportunity to bridge sophisticated engineering and medicine.
Peter J. Zimetbaum, MD, Associate Chief and Director of Clinical Cardiology at BIDMC and Associate Professor of Medicine at Harvard Medical School.
This research was supported by a grant from the Ministry of Science, Future Planning in Korea and ICT, as well as support from the National Science Foundation and the Institute of Computer Engineering and Sciences, University of Texas, Austin.