Abstract: A technique is provided for detecting episodes of cardiac ischemia based on an examination of post-T-wave signal segments. Since cardiac ischemia is often a precursor to acute myocardial infarction (AMI) or ventricular fibrillation (VF), the technique thereby provides a method for predicting the possible onset of AMI or VF so that a warning may be delivered to the patient. The warning preferably includes both a perceptible electrical notification signal applied directly to subcutaneous tissue and a warning signal delivered via short range telemetry to a handheld warning device external to the patient. In one example, the onset of cardiac ischemia is identified by detecting a sharp falling edge within post-T-wave signals by filtering the signals using a high-pass filter having a cutoff frequency of at least 1 Hz. The total amount of energy in the filtered signal is calculated and compared against various thresholds.

Abstract: A technique is provided for detecting episodes of cardiac ischemia based on an examination of the total energy of T-waves. Since cardiac ischemia is often a precursor to acute myocardial infarction (AMI) or ventricular fibrillation (VF), the technique thereby provides a method for predicting the possible onset of AMI or VF. Briefly, the technique integrates internal electrical cardiac signals occurring during T-waves and then compares the result against a running average. If the result exceeds the average by some predetermined amount, ischemia is thereby detected and a warning signal is provided to the patient. The maximum slope of the T-wave is also exploited. Techniques are also set forth herein for reliably detecting T-waves, which help prevent P-waves from being misinterpreted as T-waves on unipolar sensing channels. The T-wave detection technique may be used in conjunction with ischemia detection or for other purposes.

Abstract: A technique is provided for detecting episodes of cardiac ischemia based on an examination of the total energy of T-waves. Since cardiac ischemia is often a precursor to acute myocardial infarction (AMI) or ventricular fibrillation (VF), the technique thereby provides a method for predicting the possible onset of AMI or VF. Briefly, the technique integrates internal electrical cardiac signals occurring during T-waves and then compares the result against a running average. If the result exceeds the average by some predetermined amount, ischemia is thereby detected and a warning signal is provided to the patient. The maximum slope of the T-wave is also exploited. Techniques are also set forth herein for reliably detecting T-waves, which help prevent P-waves from being misinterpreted as T-waves on unipolar sensing channels. The T-wave detection technique may be used in conjunction with ischemia detection or for other purposes.

Abstract: A threshold sensing control for use in an implantable cardiac stimulation device controls the sensing of cardiac activity during a current cardiac cycle of a heart while avoiding sensing a T wave. The system includes a sensing circuit that senses cardiac activity of the heart during a cardiac cycle preceding the current cardiac cycle, a detector that measures selected T wave and R wave characteristics of the cardiac activity and a control circuit that varies the sensing threshold based upon the measured selected R wave and T wave characteristics. The sensing threshold control may be implemented for both intrinsic and paced beats.

Abstract: A telemetry architecture is described that enables multiple programmers to concurrently interact with associated implantable medical devices within a viable telemetry range. The programmers communicate with implantable medical devices over one or more communication channels. Inter-programmer communication is accomplished over a particular communication channel that may be selected from one of the programmer-to-device channels or via an independent back channel. The programmers use the inter-programmer communication to coordinate communication between associated programmers and implantable medical devices within the viable telemetry range.

Abstract: Exemplary methods and devices for determining whether atrial fusion, atrial pseudofusion and/or atrial native activity have occurred. Various methods and/or devices are suitable for use with atrial autocapture. Other methods, devices and/or systems are also disclosed.

Abstract: A system is provided for backing up and synchronizing data stored within a set of programmers used for programming implantable cardiac stimulation devices such as pacemakers or implantable cardioverter defibrillators (ICDs). The data from the programmers that is backed up and synchronized includes programmer software, set up and configuration data, programming parameters, patient personal data, implantable device diagnostic data, and patient diagnostic data received from implanted devices. The implanted devices are classified into one or more groups and the programmer backup system merges and synchronizes data received from all programmers within a particular group. In other words, the backup system operates to ensure that each programmer within a particular group shares the same set up and configuration data, programmer software, patient contact data, and device diagnostic information.

Abstract: A cardiac stimulation device and method to measure a myocardial conduction time and to store its long-term running average. A multipolar lead is used to deliver a stimulation pulse from a tip electrode and detect the evoked response after it has propagated to a ring electrode. The time between the stimulation pulse and a detected feature of the evoked response is determined as the myocardial conduction time. A long-term average myocardial conduction time is calculated by averaging on the order of five hundred stimulated cardiac cycles, and a running average is stored in memory. Shifts in the myocardial conduction time may be used for monitoring disease progression or the long-term response to a treatment.

Abstract: An implantable cardiac stimulation device establishes communication with at least first and second external devices which communicate using first and second communication protocols, respectively, and wherein the first and second protocols are different. The implantable device includes a pulse generator configured to generate stimulation pulses and a telemetry circuit arranged to establish communication with the first and second external devices according to the first and second communication protocols, respectively. A control circuit coupled to the telemetry circuit and the pulse generator detects the first and second external devices based upon the protocol used in establishing communication to provide a first response when the first external device is detected and a second response when the second external device is detected.

Abstract: Methods and systems for monitoring heart rate recovery are described. In one embodiment, an implantable monitoring device monitors a patient's heart activity. The monitor looks for periods of increased activity, such as those that are experienced during some level of exercise, and periods of lesser activity (such as rest) directly following. The patient's heart rate recovery is monitored as the heart recovers from the active period to the rest period. Data associated with the patient's heart rate recovery can then be diagnostically used to ascertain certain conditions associated with the patient.

Abstract: Upon interrogating a pacemaker, implantable cardioverter defibrillator or other implantable cardiac stimulation device, an external programmer accesses previously-stored physician comments maintained within the implanted device. The programmer disables any reprogramming of the implanted device until the physician comments have been displayed via the programmer for review by the physician or other medical professional seeking to reprogram the implanted device. In this manner, critical information pertaining to a previous programming session is presented to the physician before any additional reprogramming is permitted so as to ensure that the critical information is reviewed. In one example described herein, physician comments are designated as being either general or parameter-specific. General comments are displayed for review before any reprogramming is permitted. Parameter-specific comments are displayed for review only if the physician seeks to reprogram particular parameters associated therewith.

Abstract: Upon interrogating a pacemaker, implantable cardioverter defibrillator or other implantable cardiac stimulation device, an external programmer accesses previously-stored physician comments maintained within the implanted device. The programmer disables any reprogramming of the implanted device until the physician comments have been displayed via the programmer for review by the physician or other medical professional seeking to reprogram the implanted device. In this manner, critical information pertaining to a previous programming session is presented to the physician before any additional reprogramming is permitted so as to ensure that the critical information is reviewed. In one example described herein, physician comments are designated as being either general or parameter-specific. General comments are displayed for review before any reprogramming is permitted. Parameter-specific comments are displayed for review only if the physician seeks to reprogram particular parameters associated therewith.

Abstract: A cardiac stimulation device and method measure a myocardial conduction time and store its long-term running average. A multipolar lead is used to deliver a stimulation pulse from a tip electrode and detect the evoked response after it has propagated to a ring electrode. The time between the stimulation pulse and a detected feature of the evoked response is determined as the myocardial conduction time. A long-term average myocardial conduction time is calculated by averaging on the order of five hundred stimulated cardiac cycles, and a running average is stored in memory. The effect of heart rate on myocardial conduction may be taken into account by storing multiple averages corresponding to multiple pacing rates or storing the conduction time average as a function of heart rate.

Abstract: To permit remote programming of implantable cardiac stimulation devices such as pacemakers, a central device programmer is provided in conjunction with a network of remote telemetry units for use in patient homes or in remote clinics. To reprogram a device implanted within a patient, a physician enters programming commands within the central programmer which relays the programming commands to a remote telemetry unit in proximity to the patient. The remote telemetry unit, in turn, forwards the programming commands to the implanted device. In this manner, the patient need not return to the physician for reprogramming of the device. Remote telemetry units may be provided within patient homes, clinics, hospital emergency rooms, hospital patient rooms, and the like. Depending upon the implementation, different levels of programmability may be permitted depending upon the degree of supervision of the patient. For an unsupervised patient, limited programmability is permitted.

Abstract: An implantable cardiac stimulation device establishes communication with at least first and second external devices which communicate using first and second communication protocols, respectively, and wherein the first and second protocols are different. The implantable device includes a pulse generator configured to generate stimulation pulses and a telemetry circuit arranged to establish communication with the first and second external devices according to the first and second communication protocols, respectively. A control circuit coupled to the telemetry circuit and the pulse generator detects the first and second external devices based upon the protocol used in establishing communication to provide a first response when the first external device is detected and a second response when the second external device is detected.

Abstract: To permit remote programming of implantable cardiac stimulation devices such as pacemakers, a central device programmer is provided in conjunction with a network of remote telemetry units for use in patient homes or in remote clinics. To reprogram a device implanted within a patient, a physician enters programming commands within the central programmer which relays the programming commands to a remote telemetry unit in proximity to the patient. The remote telemetry unit, in turn, forwards the programming commands to the implanted device. In this manner, the patient need not return to the physician for reprogramming of the device. Remote telemetry units may be provided within patient homes, clinics, hospital emergency rooms, hospital patient rooms, and the like. Depending upon the implementation, different levels of programmability may be permitted depending upon the degree of supervision of the patient. For an unsupervised patient, limited programmability is permitted.

Abstract: An implantable cardiac stimulation device establishes communication with at least first and second external devices which communicate using first and second communication protocols, respectively, and wherein the first and second protocols are different. The implantable device includes a pulse generator configured to generate stimulation pulses and a telemetry circuit arranged to establish communication with the first and second external devices according to the first and second communication protocols, respectively. A control circuit coupled to the telemetry circuit and the pulse generator detects the first and second external devices based upon the protocol used in establishing communication to provide a first response when the first external device is detected and a second response when the second external device is detected.

Abstract: An implantable dual-chamber implantable stimulation device is used in conjunction with an external programmer to perform a capture verification procedure and then to generate a capture verification record indicative of instances where pacing pulses delivered by the implantable stimulation device have achieved capture and instances where the pacing pulses have not achieved capture. The capture verification record may also include data indicative of other cardiac and pacing events. The capture verification record is visually displayed to a medical practitioner for review and analysis. Optionally, a pacing threshold assessment test may be initiated from the programmer to determine an appropriate pacing threshold for the implantable stimulation device. A pacing threshold assessment record representative of the results of the assessment test is then generated and visually presented to the medical practitioner for review and analysis.

Abstract: An implantable cardiac stimulation system and method wherein the implanting physician may store, in the system, parameters which define the expected performance of the device in conjunction with the programming of the device to address the needs of the patient. The person performing follow-up testing of the device and its interaction with the patient may, with an external programmer, be advised of the expected performance of the device at follow-up. The implanted device generates performance data indicative of the interaction between the device and the patient's heart. Limits, defining the expected interaction of the device and the patient's heart associated with the generated data are established and stored, either in the implantable device or in the external programmer. After implant, the generated data is evaluated to determine if the generated data satisfies the established limits. The evaluation results are then reported.

Abstract: A system and method for obtaining data from an implantable medical device and delivering the data to a data processing device is disclosed. A portable interrogation device conducts a wireless interrogation of an implantable medical device implanted in a patient, and stores the data received from the implantable device in a memory of the portable interrogation device. At a later time, the portable interrogation device is directly interfaced with a data processing device using a high-speed connection, which provides the data processing device with high speed access to the interrogated data that is stored in the portable interrogation device's memory.