Towards a Leadless Wirelessly Controlled Intravenous Cardiac Pacemaker

Objective: Traditional lead-based cardiac pacemakers suffer from lead-related complications including lead fracture, lead dislodgement, and venous obstruction. Modern leadless pacemakers mitigate the complications, but since they are implanted inside the heart with a small battery, their limited battery lifetime necessities device replacement within the patient's lifetime. This paper presents a leadless and batteryless, wirelessly powered intravenous cardiac pacemaker that can potentially mitigate both problems. Methods: Wireless power is transferred at 13.56 MHz in bursts between the pacemaker modules to achieve sufficient power over the required distance for wireless pacing. The pacemaker stimulation module is designed to fit within the anatomical constraints of a cardiac vein, consume low power, apply greater than 5 V stimulation and comply with FCC SAR regulations. The module is primarily implemented in CMOS technology to achieve extreme system miniaturization. Results: Ex-vivo pacing capability was demonstrated with a system that can apply 5 V stimulation, consume 1 mW power, and operate up to 2.5 cm TX and RX separation. An in-vivo experiment verified the pacemaker functionality by increasing the heartbeat of Yorkshire pig from 64 bpm to 100 bpm. Conclusion: This work establishes that intravascular cardiac pacing can be achieved that can mitigate lead and battery-related complications. Significance: This study has a potential to advance leadless and wirelessly powered pacemaker technology.