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Electrophysiology and Arrhythmogenesis in the Human RVOT

Human RVOT susceptibility to arrhythmias

WHAT IS KNOWN?

  1. Right ventricular outflow tract (RVOT) is a common source of idiopathic ventricular arrhythmias (IVAs). 
  2. However, the mechanisms underlying the RVOT’s unique arrhythmia susceptibility remains not well elucidated due to lack of detailed electrophysiological and molecular studies of human RVOT.

WHAT THE STUDY ADDS

  1. Human RVOT electrophysiology is characterized by shorter APD relative to the right ventricular apical region and drives the transmural dispersion of repolarization and transmural APD dispersion under normal physiological conditions.
  2. Cholinergic stimulation attenuates the arrhythmogenic effects of adrenergic stimulation, including increase in frequency of PVCs and shortening of wavelength.
  3. Arrhythmia in the RV is associated with weak positive spatiotemporal autocorrelation between the epicardial-endocardial arrhythmic wavefronts and reentrant rotors that are relatively more organized in the endocardium.

LINK TO THE ARTICLE

Aras KK, Gams A, Faye NR, Brennan JB, Goldrick K, Li J, Zhong Y, Chiang C, Smith EH, Poston MD, Chivers J, Hanna P, Mori S, Ajijola O, Shivkumar K, Hoover DB, Viventi J, Rogers JA, Bernus O, Efimov IR. Electrophysiology and Arrhythmogenesis of the human right ventricle outflow tract. Circ Arrhythm Electrophysiol. 2022. (Editor’s pick)

Photocurable bioresorbable adhesives as functional intefaces between flexible bioelectronic devices and soft biological tissues

Soft interface materials for joining bioelectronic devices with biological tissues

WHAT IS KNOWN?

  1. Flexible electronic/optoelectronic systems that can physically interface with soft biological tissue surfaces offer revolutionary diagnostic and therapeutic capabilities for various diseases.
  2. However, current approaches to coupling the tissue-device interfaces either through surgical sutures, staples, cuffs, etc., damage the tissue and the devices and often result in adverse immune responses and mechanical instabilities.

WHAT DOES THIS STUDY ADD?

  1. We introduce a functional adhesive bioelectronic-tissue interface material (BTIM), which is mechanically compliant, electrically conductive, and optically transparent. The material can bond to the surface of tissue and the device and provide stable adhesion for several days to months.
  2. We demonstrate the capabilities of this material in live animal models that includes device applications ranging from battery-free optoelectronic systems for deep-brain optogenetics to wireless millimeter-scale pacemakers and flexible multi electrode epicardial arrays.

LINK TO THE ARTICLE

Yang Q, Wei T, Yin RT, Wu M, Xu Y, Koo J, Choi YS, Xie Z, Chen SW, Kandela I, Yao S, Deng Y, Avila R, Liu TL, Bai W, Yang Y, Han M, Zhang Q, Haney CR, Benjamin Lee K, Aras K, Wang T, Seo MH, Luan H, Lee SM, Brikha A, Ghoreishi-Haack N, Tran L, Stepien I, Aird F, Waters EA, Yu X, Banks A, Trachiotis GD, Torkelson JM, Huang Y, Kozorovitskiy Y, Efimov IR, Rogers JA. Photocurable bioresorbable adhesives as functional interfaces between flexible bioelectronic devices and soft biological tissues. Nat Mater. 2021 Jul 29;. doi: 10.1038/s41563-021-01051-x. [Epub ahead of print] PubMed PMID: 34326506.

Book chapter: conformal electronics therapy for defibrillation

Book

Cardiac Bioelectric Therapy: Mechanisms and Practical Applications

Chapter 38

Conformal Electronics Therapy for Defibrillation

Authors

Kedar K. Aras, John A. Rogers, Igor R. Efimov

Abstract

Defibrillation remains the only effective therapy against sudden cardiac death. However, the current coil-based lead ICD devices are limited by high defibrillation threshold (DFT) and low arrhythmia sensing resolution, which can result in inappropriate and painful shocks adversely affecting the quality of life. Emerging classes of materials and mechanics concepts in the field of flexible and stretchable electronics have created new opportunities for integrating high-performance electronics with the human body and its organs and various tissues. These conformal electronics devices offer a platform for high-definition arrhythmia sensing to minimize inappropriate shocks and improve therapy and high-definition therapy delivery circuit to reduce DFT.