摘要:
An apparatus comprising an implantable cardiac signal sensing circuit configured for sensing an intrinsic cardiac signal, a memory to store a template of a morphology of normal atrial-ventricular conduction, and a controller that includes a tachyarrhythmia detection circuit and a correlation circuit. The tachyarrhythmia detection circuit is configured for detecting a rhythm with elevated ventricular rate using the sensed intrinsic cardiac signal. The correlation circuit is configured for iteratively calculating a correlation between the sensed intrinsic cardiac signal and the template, and comparing the calculated correlation to a variable correlation threshold to determine whether the detected rhythm correlates to the template. The apparatus also includes a therapy circuit configured for inhibiting a ventricular tachycardia therapy when the detected rhythm correlates to the template. Other apparatuses and methods are described.
摘要:
A cardiac rhythm management system can be used to detect episode beats associated with cardiac events in a subject's body. These events may be monitored and depolarization morphology information can be derived for candidate arrhythmic beats in an arrhythmia episode. An arrhythmic beat morphology template may be formed from selecting at least one of the candidate arrhythmic beats based upon user's labeling according to specific morphologies of one or more candidate episodes. Methods of use are also presented.
摘要:
This document discusses, among other things, detection of a sudden onset of a tachyarrhythmia. A sudden onset of tachyarrhythmia is determined by monitoring changes in intrinsic ventricular rate, such as by using one or more sensing channels in the ICD. A lowest tachyarrhythmia rate threshold is accompanied by a slightly lower “hysteresis tachyarrhythmia rate threshold.” If a sudden onset of tachyarrhythmia is declared, the sudden onset status is not reset by the ventricular rate falling below the lowest tachyarrhythmia rate threshold, but is instead reset by the ventricular rate falling below the slightly lower hysteresis tachyarrhythmia rate threshold.
摘要:
A cardiac rhythm management system can be used to detect episode beats associated with cardiac events in a subject's body. These events may be monitored and depolarization morphology information can be derived for candidate arrhythmic beats in an arrhythmia episode. An arrhythmic beat morphology template may be formed from selecting at least one of the candidate arrhythmic beats based upon user's labeling according to specific morphologies of one or more candidate episodes. Methods of use are also presented.
摘要:
This document discusses, among other things, detection of a sudden onset of a tachyarrhythmia. A sudden onset of tachyarrhythmia is determined by monitoring changes in intrinsic ventricular rate, such as by using one or more sensing channels in the ICD. A lowest tachyarrhythmia rate threshold is accompanied by a slightly lower “hysteresis tachyarrhythmia rate threshold.” If a sudden onset of tachyarrhythmia is declared, the sudden onset status is not reset by the ventricular rate falling below the lowest tachyarrhythmia rate threshold, but is instead reset by the ventricular rate falling below the slightly lower hysteresis tachyarrhythmia rate threshold.
摘要:
An implantable cardioverter/defibrillator (ICD) executes a rate accuracy enhancement algorithm to select measured atrial and ventricular intervals for classifying a detected tachycardia based on average atrial and ventricular rates calculated from the selected atrial and ventricular intervals. The detected tachycardia is classified as ventricular tachycardia (VT) if the average ventricular rate is substantially higher than the average atrial rate.
摘要:
An atrial cardioverter for cardioverting atria of a heart while sustaining atrial pacing of the heart. The cardioverter includes a pacer for pacing the heart in one of a plurality of modes including an atrial pacing, atrial inhibited mode, and an atrial pacing, ventricular inhibited mode, an atrial tachyarrhythmia detector for detecting an atrial tachyarrhythmia of the heart, and a mode control for changing the mode of the pacer from the atrial pacing, atrial inhibited mode to the atrial pacing, ventricular inhibited mode responsive to the atrial tachyarrhythmia detector detecting an atrial tachyarrhythmia of the heart. A cardioverter stage applies cardioverting energy to the atria responsive to the atrial tachyarrhythmia detector detecting an atrial tachyarrhythmia and after the pacer mode change.
摘要:
An implantable atrial defibrillator applies cardioverting electrical energy to the atria of a human heart in need of cardioversion after first determining if there is an absence of potential atrial fibrillation. A sensor associated with the atria of the heart senses activity of the heart and generates a cardiac signal and a first detector detects cardiac events from the cardiac signal. A second detector responsive to time spans between immediately successive detected cardiac events which are grater in duration than a preselected interval detects for an absence of potential atrial fibrillation. An atrial fibrillation detector detects for atrial fibrillation if the second detector fails to detect an absence of atrial fibrillation, and a cardiovertor applies cardioverting electrical energy to the atria when the atria are in fibrillation.
摘要:
An implantable cardioverter/defibrillator (ICD) delivers atrial pacing under several scenarios during a tachyarrhythmia episode that is detected using a ventricular rate. In various embodiments, the atrial pacing terminates the detected tachyarrhythmia and/or enhances the classification of the detected tachyarrhythmia, thus avoiding ineffective and/or unnecessary delivery of a ventricular anti-tachyarrhythmia therapy when the detected tachyarrhythmia has a supraventricular origin.
摘要:
An apparatus comprises an implantable ventricular depolarization sensing circuit configured to provide a sensed ventricular depolarization signal, a timer circuit configured to provide a ventricular time interval between ventricular depolarizations, and a controller circuit communicatively coupled to the ventricular depolarization sensing circuit and the timer circuit. The controller circuit includes a ventricular tachycardia (VT) detection circuit configured to declare an episode of VT when a number of accelerated beats are detected, calculate a hysteresis VT detection threshold interval, and deem whether the episode of VT persists using the hysteresis VT detection threshold interval.