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: 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: An implantable medical device that includes a microprocessor that characterizes cardiac activity of a patient to enable the implantable medical device to deliver therapy in response to an identified arrhythmia event. A monitor/controller monitors the characterized cardiac activity and the delivered therapy, and controls activation of triggered overdrive pacing subsequent to the delivered therapy.

Abstract: A system and method for treating an arrhythmia of the heart, involves delivery of anti-tachy pacing (ATP) pulses to the heart, possibly followed by the delivery of a high-voltage shock. ATP delivery is controlled such that the time delivery of any high-voltage shock is not affected by the prior delivery of the ATP pulses. System control may be accomplished using one or more programmable parameters, which may include a user-specified shock energy.

Abstract: In an IMD, when tachyarrhythmia detection criterion are satisfied or a high intrinsic heart rate is detected, a peak amplitude detection circuit is enabled to detect the peak amplitude of the cardiac signal of interest, i.e., the P-wave in the case of atrial tachyarrhythmias and the R-wave in case of ventricular tachyarrhythmias. Peak amplitude data is accumulated for subsequent use in setting sensing thresholds and/or gain of a sense amplifier to reduce undersensing of lower amplitude cardiac signals during such tachyarrhythmias.

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: 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: A monitoring device for implant in a patient's body. The device is provided with a physiologic sensor generating output signals, which signals are stored as numerical values. The device defines first monitoring periods limited to time periods during successive nights during which the patient is likely to be asleep, stores the numerical values generated during the first monitoring periods in a memory and calculates values reflecting general levels of the numerical values during the first monitoring periods. The device may also or alternatively define second monitoring periods limited to time periods during successive daytime and store numerical values generated during the second monitoring periods. The physiologic sensor may be an electrogram amplifier or other sensor indicative of metabolic demand for oxygenated blood, such as an activity sensor.

Abstract: An implantable medical device that includes a microprocessor that characterizes cardiac activity of a patient to enable the implantable medical device to deliver therapy in response to an identified arrhythmia event. A monitor/controller monitors the characterized cardiac activity and the delivered therapy, and controls activation of triggered overdrive pacing subsequent to the delivered therapy.

Abstract: The present invention provides a system and method for treating an arrhythmia of the heart. The system and method involves delivery of anti-tachy pacing (ATP) pulses to the heart, possibly followed by the delivery of a high-voltage shock. ATP delivery is controlled such that the time of delivery of any high-voltage shock is not affected by the prior delivery of the ATP pulses. System control may be accomplished using one or more programmable parameters, which may include a user-specified shock energy.

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: An implantable monitoring device for monitoring a patient's heart rate variability over time. The device includes a cardiac electrogram amplifier, a sensing electrode coupled to an input of the amplifier, timing circuitry, processing circutry and a memory. The timing circuitry defines successive monitoring periods each extending over a period of hours, the monitoring periods together extending at least over a period of weeks and also defines successive shorter time periods during each monitoring period. The memory stores heart intervals between depolarizations of the patient's heart sensed by the amplifier during the shorter time periods. The processing circuitry calculates median intervals between depolarizations of the patient's heart sensed by the amplifier during the shorter time periods and calculates standard deviations of the median intervals calculated during each monitoring period.

Abstract: A system including an implantable medical device and an associated external device, in which the implantable device is adapted to monitor a physiologic parameter and includes a telemetry system for transmitting information to and receiving information from the external device, including information regarding the measured physiological parameter and in which wherein the external device includes a telemetry system for receiving information from the implanted device and for transmitting information to the implanted device and is provided with a mechanism for receiving information indicative of occurrences of significant therapeutic events and is further provided with a display system which combines information received from the implantable device related to the monitored physiologic parameter with the information of therapeutic significance and for displays the combined information in a time-scaled display in which the measured physiologic parameter is displayed along a common time scale with indications of occu

Abstract: An implantable medical device determines activity levels over a set of time periods, preferably on the order of seconds, minutes and hours and a display is enabled for days or weeks at recorded activity levels over a range of dates. This enables physical review of patient functional status. Additional physiologic data can be recorded along with the activity data, and this too may be reported out from the implanted device to a medical communications system for alarm purposes, filtrating drugs or other monitoring tasks.

Abstract: An implantable medical device determines activity levels over a set of time periods, preferably on the order of seconds, minutes and hours and a display is enabled for days or weeks at recorded activity levels over a range of dates. This enables physician review of patient functional status. Additional physiologic data can be recorded along with the activity data, and this too may be reported out from the implanted device to a medical communications system for alarm purposes, titrating drugs or other monitoring tasks.

Abstract: An implantable medical device determines activity levels over a set of time periods, preferably on the order of seconds, minutes and hours and a display is enabled for days or weeks at recorded activity levels over a range of dates. This enables physician review of patient functional status. Additional physiologic data can be recorded along with the activity data, and this too may be reported out from the implanted device to a medical communications system for alarm purposes, titrating drugs or other monitoring tasks.

Abstract: A pulsed Doppler probe 10 for monitoring blood flow within a blood vessel 12 includes a sheath 17 and a plurality of electrically conductive wires 26 extending through the sheath 17. The wires 26 have distal ends 28 to which an ultrasonic transducer 18 is operatively connected. The transducer 18 has an operative surface 20, and the probe 10 also includes a means 22 for fixing the orientation of the operative surface 20 with respect to at least one of a longitudinal axis 38 of the sheath 17, and the orientation fixing means 22, or with respect to the distal ends 28 of the electrically conductive wires 26. The orientation fixing means 22 includes an epoxy material 24 encasing the ultrasonic transducer 18, shaped to include a cylindrically concave surface 30. The probe 10 further includes a mesh band 44 of at least one of an absorbable material and an inert material adapted to encircle the blood vessel 12.

Abstract: A method and system for non-invasively detecting Coronary Artery Disease. The method comprises analyzing the diastolic heart sounds detected from a patient's chest cavity during the diastolic portion of the heart cycle in order to identify a low level auditory component associated with turbulent blood flow in partially occluded coronary arteries. These diastolic heart sounds are modeled using advanced signal processing techniques such as Autoregressive (AR), Autoregressive Moving Averaging (ARMA) and Eigenvector methods, so that the presence of such an auditory component may be reliably indicated even under high noise conditions. The system includes an acoustic transducer, pulse sensor device, signal processor means and a diagnostic display. Additionally, the system includes a controller for automatically sequencing data collection, analysis and display stages, therefore requiring a minimum of operator interaction.