Heart failure can be treated by pacemakers to keep the beats in rhythm, but pacemakers apply electrical stimulation at specific points and do not provide comprehensive coverage of the entire organ. In a paper published online by Science Translational Medicine on June 22, researchres from the IBS Center for Nanoparticle Research (led by Director Taeghwan HYEON) devised an electric mesh that wraps around the heart to deliver electrical impulses to the whole chamber of the heart (ventricular myocardium).

The heart wrap was made from silver nanowires embedded in a rubber polymer that could conform to the unique three-dimensional anatomy of different hearts.

In rats that had a heart attack, the mesh integrated structurally and electrically with the cardiac muscle (myocardium) and exerted beneficial effects, including preserved diastolic relaxation, reduced wall stress, and improved cardiac contractile function. The mesh also terminated induced abnormal rapid heart rhythms (ventricular arrhythmia), acting as an epicardial defibrillator, which is designed to give an electric shock to the heart. This helps reestablish normal contraction rhythms in the heart.

Such epicardial meshes have been tested in clinical trials before and were effective in preventing ventricular remodeling but showed controversial results in long-term survival. The researchers hope that their device, which is designed to integrate more faithfully with the heart’s structure and electrical conduction system, is more consistent in people.

Go to the link below for more details.
http://stm.sciencemag.org/content/8/344/344ra86

* Citation: The entire text above is from the Editor's Summary of the paper that is published online in Science Translational Medicine.

▲ 1. Materials and design strategy of an elasto-conductive epicardial mesh.
(A) Schematic illustration of the design strategy of an epicardial mesh for electromechanical cardioplasty in accordance with electrophysiological conduction in the cardiac system. Conductive nanowires were homogeneously dispersed in SBS rubber, allowing for electrical signal (e?) transfer during the entire cardiac cycle.
(B) Scheme of the reaction for LE-AgNW (top). The ligand of AgNW was exchanged from PVP to HAm via NOBF4 treatment. A scanning electron microscopy image of LEAgNW/ SBS nanocomposite is shown.

▲ Personalized design of the epicardial mesh.

▲ Coupling of the epicardial mesh to the rat heart.
(B) Surface ECG (lead II) and intracardiac electrograms recorded from a conventional electrode on the RV and the epicardial mesh encircling the heart. p, p-wave; v, ventricle; a′, atrium.

▲ The effect of electrical stimulation on cardiac electrical and mechanical function and defibrillation function by the epicardial mesh.
Surface ECG depicting occurrence of a wide-QRS tachycardia, identified as nonsustained ventricular tachycardia from the epicardial mesh recording. (G) Degeneration to ventricular fibrillation (VF) 3 s later and successful termination with a biphasic electrical shock of 2 J delivered through the epicardial mesh. During all assessments, the cycle length of pacing was 280 ms

Notes for editors

- References
Jinkyung Park, Suji Choi, Ajit H. Janardhan, Se-Yeon Lee, Samarth Raut, Joao Soares, Kwangsoo Shin,Shixuan Yang, Chungkeun Lee, Ki-Woon Kang, Hye Rim Cho, Seok Joo Kim, Pilseon Seo, Wonji Hyun, Sungmook Jung, Hye-Jeong Lee, Nohyun Lee, Seung Hong Choi, Michael Sacks, Nanshu Lu, Mark E. Josephson, Taeghwan Hyeon, Dae-Hyeong Kim, Hye Jin Hwang (2016) Electromechanical cardioplasty using a wrapped elasto-conductive epicardial mesh, Science Translational Medicine, DOI: 10.1126/scitranslmed.aad8568

- Media Contact
For further information or to request media assistance, please contact: Mr. Shi Bo Shim, Head of Department of Communications, Institute for Basic Science (+82-42-878-8189; sibo@ibs.re.kr) or Ms. Dahee Carol Kim, Department of Communications, Institute for Basic Science (+82-42-878-8133; clitie620@ibs.re.kr)

- About the Institute for Basic Science (IBS)
IBS was founded in 2011 by the government of the Republic of Korea with the sole purpose of driving forward the development of basic science in Korea It comprises a total of 50 research centers in all fields of basic science, including mathematics, physics, chemistry, life science, earth science and interdisciplinary science. IBS has launched 26 research centers as of June 2016. There are 8 physics, 1 mathematics, 6 chemistry, 8 life science and 3 interdisciplinary research centers.