Abstract: Described herein are external devices, and methods for use therewith, that are configured to communicate with one or more implantable medical devices (IMDs) implanted within a patient using conductive communication, wherein the external device includes or is communicatively coupled to at least three external electrodes that are in contact with the patient. Certain such methods involve the external device identifying, for each IMD, of the plurality of IMDs, which one of the plurality of communication vectors is a preferred communication vector for communicating with the IMD, based on respective indicators of conductive communication quality that are determined for the plurality of communication vectors. Certain embodiments involve determining when there should be a reassessment of which one of the plurality of communication vectors is the preferred communication vector for communicating with an IMD, and in response thereto, identifying an updated preferred communication vector for communicating with the IMD.

Abstract: Electroporation-based therapies (EBTs) employ high voltage pulsed electric fields (PEFs) to permeabilize tumor tissue, resulting in changes in passive electrical properties detectable using electrical impedance spectroscopy (EIS). Currently, commercial potentiostats for EIS are limited by impedance spectrum acquisition time (˜10 s); this timeframe is much larger than pulse periods used with EBTs (˜1 s). Fourier Analysis SpecTroscopy (FAST) is introduced as a methodology for monitoring tissue inter-burst impedance (diagnostic FAST) and intra-burst impedance (therapeutic FAST) during EBTs. FAST is a rapid-capture (<<1 s) technique which enables monitoring of inter-burst and intra-burst impedance during EBTs in real-time. FAST identified a frequency which delineates thermal effects from electroporation effects in measured impedance. Significance: FAST demonstrates the potential to perform EIS, in addition to intra-burst impedance spectroscopy, using existing pulse generator topologies.