Optical Techniques for Future Pacemaker Technology

Abstract

Current muscle pacemaker technology mostly relies on electrical techniques. The electrical method is well understood and established, however, the electricity is difficult to localize and has a risk of interfering with intact cells, tissues, and organisms, affecting their electrophysiology. Light has the potential to be a novel medium in future pacemaker technology. Light is typically minimally invasive and has low interactivity with biological tissues. Depending on the wavelength, this unique property allows its use to access deep inside biological tissues and opens up potential extension of light and photonics technology to a variety of applications in biosciences, such as in vivo manipulation of biological functions. Combined with nonlinear optical technology, only light technology allows location-selective manipulation deep inside tissues with minimum disturbance to the surrounding areas. Other light properties, such as an inherent sterility and the fact that it does not interfere with measurement instruments, makes the technology attractive. In this chapter, we describe light-based techniques that may be used for future muscle pacemaker technology. Recently we presented femtosecond laser pacemaker for heart muscle cells through nonlinear light technology. This chapter describes details of light interaction with cells and in particular muscle cells, including experimental and modeling studies. Besides nonlinear light technology, other light-based techniques for manipulating muscle activities are reviewed. These techniques may not be able to pace muscle activities, but are still worth considering since they can change the beat rate. In the latter part, this chapter also includes indirect light-tissue interactions mediated by implanted pacemaker devices, such as rechargeable battery and transcutaneous telemetry systems for both deliverying power to an implanted pacemaker and also for monitoring pacemaker function. The light-driven and light-mediated implanted devices may in the future play an important role in developing implanted pacemaker technology. Light-based pacemaker technology has just started recently and the interaction effect is partially unclear and needs to be studied more precisely. The light-based technology, however, has significant and perhaps surprising potential for pacemaker technology. In the future, light-based techniques may not only shed light on the future development of pacemaker technology but can also help understandings of basic underlying science in fatal