Bereuter, Lukas David; Küffer, Thomas; Artik, Emir; Niederhauser, Thomas; Obrist, Dominik; Tanner, Hildegard; Haeberlin, A. (17 May 2017). Towards a Leadless Cardiac Multisite Pacemaker System. Cardiovascular medicine - supplementum, 20(5), S75-S75. EMH Swiss Medical Publishers Ltd
Introduction
Recently, leadless pacemakers have been introduced to overcome the drawbacks associated with pacemaker leads. However, these leadless pacemakers are single-chamber systems, although dual-chamber or even multisite pacing would provide a more physiologic myocardial excitation. We aim at developing a leadless multisite pacemaker system, featuring several single leadless pacemakers (e.g. one in the right atrium and one in the right ventricle) that communicate wirelessly with each other. To retain the pacemakers’ longevity, it is crucial that the communication method is power efficient (modern pacemakers consume only 5-10 µW of power).
Method
We implemented conductive intra body communication (IBC) into a leadless multisite pacemaker system. IBC makes use of the electrical conductivity of tissue, i.e. uses the myocardium as signal carrier. In a first step, we electrically characterized the myocardium of porcine hearts by performing in-vivo and in-vitro impedance measurements in the frequency range from 10 kHz to 18 MHz. Based on the resulting transfer function, we developed prototypes of communication modules that are optimized for communication via the myocardial tissue.
Results
The developed leadless communication modules feature multisite pacing and are capable of performing continuous bidirectional communication between the atrium and the ventricle. The functionality of the modules was tested in-vitro and in-vivo on porcine hearts. The lowest damping of the communication signal (15-25 dB) was obtained at frequencies between 500 kHz and 2 MHz. Less than 1 µW of average power was dissipated into the tissue for synchronization.
Conclusion
We showed the potential of a low-power leadless communication method suitable for leadless pacemakers. By integrating this technique into leadless pacemakers, it may be possible to build a leadless multisite pacemaker system.