Embodiments relate to an implantable cardiac system and methods, including a housing, electronic circuitry for controlling one or more of power management, processing unit, information memory and management circuit, sensing and simulation output and how these operate. The system also includes diagnosis and treatment software for diagnosing health issues, diagnosing mechanical issues, determining therapy output and manage patient health indicators over time, a power supply system including at least one rechargeable battery, a recharging system, an alarm (or alert) system to inform patient of energy level and integrity of system, communication circuitry, one or more electrodes for delivering therapeutic signal to a heart and one or more electrodes for from delivering electrocardiogram signal from the heart to the electronic circuitry, and body orientation determination, in various aspects.