Abstract: Apparatus and methods are provided for analyzing an episode stored by an implantable medical device (IMD) using prior probability and conditional probability information to determine the likelihood of a particular diagnosis for a given stored episode. Certain embodiments include retrieving information about a stored episode from an IMD, including an episode metric, and retrieving domain expert information about potential diagnoses and episode metrics to determine the likelihood that the stored episode was due to a particular potential diagnosis. Certain embodiments also include retrieving patient information including a patient metric, such as patient demographics, or patient history. Certain embodiments of the invention include the ability to automatically or manually update or change the domain expert information.

Abstract: A system and method for post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by a medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and verifies, in response to the transmitted data, whether the determined instances should have been identified by the medical device as a cardiac event being detected.

Abstract: A method and system of post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and determines whether there is an abrupt onset of the cardiac event in response to the transmitted data.

Abstract: A system and method for determining oversensing during post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, identifies and removes suspected far-field R-waves, and determines whether a signal including the removed suspected far-field R-waves is regular.

Abstract: A method and system of post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and determines, in response to the transmitted sensing data, whether one of the sensed ventricular events and the sensed atrial events is initiating conduction of a heart associated with the stored sensing data.

Abstract: A method and system for post-processing of sensing data associated with identification of a cardiac event by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and generates a template in response to correlated morphologies of adjacent intervals prior to a detection interval corresponding to the cardiac being identified as the cardiac event and a morphology of the detection interval.

Abstract: A method and system of post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and determines a ratio of sensed atrial events to sensed ventricular events in response to the transmitted data.

Abstract: A method and system for determining undersensing during post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and determines whether one of a predetermined number of undersensing criteria have been met in response to the transmitted data.

Abstract: A method for identifying and classifying various types of oversensing in implantable medical devices (IMDs), such as implantable cardioverter defibrillators (ICDs), to assist a physician in choosing corrective action to reduce the likelihood of oversensing and inappropriate therapy delivery. Far-field electrogram (EGM) signals are analyzed to detect the occurrence of R-waves, and the result is compared to the number and pattern of R-waves sensed by the IMD and indicated on the marker channel. A marker channel with more sensed R-waves than indicated by analysis of the far-field EGM indicates the presence of oversensing, including double-counting of R-waves, T-wave oversensing, lead malfunction or failure, poor lead connections, noise associated with electromagnetic interference, non-cardiac myopotentials, etc.

Abstract: An implantable cardioverter defibrillator (ICD) senses ventricular depolarizations (R-waves) in an electrogram signal to detect a ventricular tachycardia or fibrillation episodes. The EGM signal is also monitored in real time for characteristics that uniquely identify instances of T-wave oversensing. The ICD determines whether detection of a tachycardia or fibrillation episode is appropriate based upon counts of each of the unique characteristics evidencing T-wave oversensing.

Abstract: An implantable cardioverter defibrillator (ICD) automatically determines whether to use electrogram (EGM) signals sensed by a true bipolar electrode pair or those sensed by an integrated bipolar electrode pair. EGM signals from both the true bipolar pair and the integrated bipolar pair are simultaneously sensed and compared to determine which pair produced more accurate sensing of cardiac events. The more accurate source of EGM signals is selected and used in determining the therapy to be delivered.

Abstract: A method and apparatus for determining oversensing in an implantable medical device that includes sensing a first cardiac signal and detecting cardiac events via a first electrode configuration, determining the presence of an episode requiring therapy in response to the detected cardiac events, sensing the first cardiac signal via a second electrode configuration, determining a baseline measurement of samples of the first cardiac signal sensed via the second electrode configuration, and determining whether to deliver therapy in response to the baseline measurement.

Abstract: A method and apparatus for determining oversensing in a medical device that includes sensing cardiac signals and detecting cardiac events via a first electrode configuration, determining the presence of an episode event in response to the detected cardiac events, and sensing the cardiac signals via a second electrode configuration. Amplitudes associated with a predetermined number of cardiac signals sensed via the second electrode configuration corresponding to the event episode are determined, and delivery of therapy is controlled in response to the determined amplitudes.

Abstract: A method for delivering therapy in a medical device that includes a two-tiered approach of determining the presence of a lead-related condition, and determining, in response to a lead-related condition being present, the presence of oversensing. Deliver of therapy by the medical device is controlled in response to determining that both the lead-related condition and oversensing are present.

Abstract: A method and apparatus for detecting a lead-related condition that includes determining whether a first oversensing criteria is satisfied, determining whether a second oversensing criteria is satisfied, determining whether an impedance criteria has been satisfied, and generating an alert in response to more than one of the first oversensing criteria, the second over sensing criteria and the impedance criteria being satisfied.

Abstract: A device for efficiently, accurately and consistently securing dental casts while an articulator is attached thereto includes a spine connecting a first stabilizing pad at one end to a second stabilizing pad at an opposite end. The device includes a breakaway feature which allows a connection between the casts to be broken with manual force. The first stabilizing pad and the second stabilizing pad are secured to maxillary and mandibular casts with an adhesive or the like, or by other methods such as magnets, to create a rigid connection between the accurately related maxillary and mandibular casts. The breakaway feature allows a technician to easily break the connection between the maxillary and mandibular casts with manual force after the articulator has been attached to the casts.

Abstract: An implantable cardioverter/defibrillator provided with method and apparatus for discrimination between tachycardia and fibrillation. The device is measures the interval separating depolarization of the heart, sorts the measured interval into interval ranges, counts the number of intervals in each range, and, based on the distribution of intervals within the rate ranges, identifies tachycardia or fibrillation. In its preferred embodiment, the device triggers delivery of therapies appropriate for treatment of tachycardia and fibrillation.