Abstract: Systems and methods for providing a cardiac stimulus device lead having fault tolerance and fault isolation are disclosed. A medical electrical lead is provided according to one aspect. According to one embodiment, the lead includes a first conductor and a second conductor for transmitting an electrical pulse from a pulse generator. The lead further includes a switching mechanism, a first electrode, and a lead assessment circuit. The switching mechanism selectively couples the first conductor to the first electrode. The first electrode is decoupled during a test phase and the switching mechanism directly couples the first conductor to the second conductor. The lead assessment circuit processes a signal associated with the electrical properties of the lead to determine whether the lead is exhibiting a lead related condition.

Abstract: The present invention provides diverse methods and apparatus for in vivo monitoring, detecting and/or predicting potential failure modes or deleterious trends of chronically implanted medical electrical leads prior to actual failure of said leads. Certain embodiments of the invention involve applying a relatively increased data sampling rate at various time intervals (e.g., periodically, randomly, and/or manually-triggered and the like) prior to actual detection of a deleterious trend, to thereby increase the probability of detecting one or more parameters indicative of a potential lead performance issue. At least some of the parameters are utilized because they are not typically reliably detected at relatively lower data sampling rates.