Non-optogenetic approaches for leadless cardiac pacing: Mechanically induced excitation for extracorporeal control of cardiac rhythm

Implantable electrical pacemakers are a life-saving intervention, however suffer from various limitations (such as infection, thrombosis, generator or lead failure, lack of autonomic responsiveness, interactions with magnetic fields, etc.) and require (minimally invasive) surgical implantation. In the emergency setting, bradycardia or asystole are life-threatening conditions that require rapidly applied extracorporeally induced pacing during resuscitation, transportation, or as a bridge to permanent pacemaker implantation. Transcutaneous electrical pacing through the chest wall is a useful technique for temporary pacing in emergency cases but is painful and not practical for prolonged use. Mechanical pacing represents a rapidly available, non-invasive, means of extracorporeal pacing, which has been demonstrated to be safe, well-tolerated, and applied by simple, readily available means (such as precordial percussion) or through emerging technologies (such as high intensity focused ultrasound or injectable magnetic microparticles). This chapter addresses the mechanisms, application, challenges, and future directions of mechanical pacing for clinical use.