Abstract: A system and method for delivering both anti-tachy pacing (ATP) therapy and high-voltage shock therapy in response to detection of abnormal cardiac rhythms is disclosed. The system controls the time between delivering ATP therapy and the charging of high-voltage capacitors in preparation for shock delivery based on a predetermined set of criteria. In one embodiment, the inventive system operates in an ATP During Capacitor Charging (ATP-DCC) mode wherein all, or substantially all, of the ATP therapy is delivered during charging of the high-voltage capacitors. Based on evaluation of the predetermined set of criteria, the system may switch to an additional ATP Before Capacitor Charging (ATP-BCC) mode, wherein substantially all of the ATP therapy is delivered prior to charging of the high-voltage capacitor. According to one aspect of the invention, the predetermined set of criteria is based, at least in part, on the effectiveness of previously-delivered ATP therapy.

Abstract: The invention provides systems to prevent the delivery of antitachycardia pacing (ATP) following a defibrillation threshold (DFT) induction at implant. An algorithm that classifies episodes as induced or spontaneous is implemented, thereby enabling the ATP during charging feature to be operable only when spontaneous episodes are detected while temporarily suspending the ATP feature during the delivery of defibrillation shock after induction has been confirmed. Further, a user interface enables users to interact with an implantable medical device (IMD), particularly for setting a defibrillation threshold (DFT) or a 50 Hz burst from a single programmer screen. The user interface includes various functionalities to promote quick user access to parameters that govern diagnosis, therapy and other features of the IMD. A single screen enables the user to complete automatic and/or manual DFT inductions or a 50 Hz burst from a programmer interface while acquiring associated documentation from the same interface.

Abstract: An implantable medical device (IMD) identifies suspected non-lethal ventricular arrhythmia, and takes one or more actions in response to the identification to avoid or delay delivery of a defibrillation or cardioversion shock. The IMD employs number of intervals to detect (NID) thresholds for detection of ventricular arrhythmias. When a NID threshold is met, the IMD determines whether the ventricular rhythm is a suspected non-lethal rhythm despite satisfying a NID threshold. In some embodiments, the IMD increases the NID threshold, i.e., extends the time for detection, in response to identifying a rhythm as a suspected non-lethal rhythm, and monitors subsequent ventricular beats to determine if the increased NID threshold is met before detecting a ventricular arrhythmia and delivering therapy. The IMD can determine whether a rhythm is a suspected non-lethal arrhythmia by, for example, comparing the median ventricular cycle length (VCL) to the median atrial cycle length (ACL).