The invention addresses possible fault scenarios including exposure to electromagnetic interference (EMI) which can include radio frequency (RF) electromagnetic radiation due to one or more security and/or communication regimens as well as various imaging modalities such as magnetic resonance imaging (MRI), positron electron transmission (PET) imaging or the like. In one aspect, an active implantable medical device (AIMD) is configured to sense a physiologic parameter of a patient and provide a therapy such as cardiac pacing, high-energy cardioversion/defibrillation therapy and/or a drug or substance delivery regimen. An implantable physiologic sensor (IPS) couples to the AIMD with coaxial conductors with the inner conductor carrying the IPS output signals thus avoiding output signal degradation due to EMI. That is, the outer conductor couples to ground providing electromagnetic protection (e.g., like a Faraday cage) to the inner conductive and the output signals.