27 February 2019
Vol 11, Issue 481

About The Cover

Cover image expansion

ONLINE COVER Light Hearted. Atrial fibrillation is an irregular heartbeat (arrhythmia) that disrupts normal blood flow, increasing the risk of stroke, blood clots, and sudden cardiac arrest. This conceptual image depicts an alternative to an implanted cardioverter-defibrillator, a device that provides electrical shocks (cardioversion) to correct arrhythmia. Nyns et al. developed an implantable system combining a cardiac rhythm monitor, optogenetics to paint viral vectors encoding light-activatable ion channels onto atrial tissue (blue in image), and a light source to trigger ion channel activation in response to arrhythmia. When implanted into adult rats, this system could detect and terminate arrhythmia without the need for electrical shocks. [CREDIT: 123RF.COM]