摘要:
A clinical programming system is disclosed for use with an implanted cardiac pacemaker to automatically determine the minimum pacing energy which is necessary to evoke a ventricular depolarization. The system utilizes a series of pacing pulses of progressively decreasing energies to stimulate the ventricle, and detects evoked responses through measurements of the integrals of the R-waves provided by a surface electrocardiogram. Upon loss of capture, the minimum pacing energy is a function of the energy of the last pacing pulse which evoked a ventricular depolarization.
摘要:
A clinical programming system for use with an implanted cardiac pacemaker to automatically determine the minimum pacing energy which is necessary to evoke an atrial depolarization. The system utilizes a series of pacing pulses of progressively decreasing energies to stimulate the atrium, and detects an evoked response during the AV delay interval that follows each pulse. Initial P-wave intervals are subjected to morphological analysis to generate a P-wave template. Subsequent intervals are similarly analyzed and the results compared with the template. The absence of similarity with the template indicates the loss of atrial capture and that the minimum pacing energy has been reached.
摘要:
A clinical programming system is disclosed for use with an implanted cardiac pacemaker to automatically determine the minimum pacing energy which is necessary to evoke an atrial depolarization. The system utilizes a series of pacing pulses of progressively decreasing energies to stimulate the atrium and detects following R-waves. The absence of an R-wave indicates the loss of atrial capture.
摘要:
In an implantable antiarryhythmia pacemaker, an automatic cardiac arrhythmia detection and classification monitoring apparatus and method for measuring stimulated intracardiac electrogram potentials, deriving therefrom a paced depolarization integral (PDI), analyzing time-based changes in the PDI, detecting and classifying harmful cardiac rhythms while distinguishing harmful from benign tachycardias, and automatically establishing and initiating an appropriate therapy, if necessary, to revert the arrhythmia condition.
摘要:
A physiological event signal sensing system in a cardiac control or monitoring device for detecting spontaneous cardiac electrical events which may be obscured by continuous or burst EMI line frequency noise. The noise rejecting sensing system of this invention senses and samples cardiac signals which may include a noise component which is produced by power line interference in addition to a physiological signal component. The sampling frequency is selected to be an integer multiple of at least one common power line frequency. The system notch filters the cardiac signal to remove line frequency components, using either or both lowpass and highpass notch filtering coefficients, then limits the filtered output to the amplitude of the corresponding filter input to remove filter output signals caused by the sudden termination of line frequency noise which is characteristic of burst noise.
摘要:
An implantable device and method for treating cardiac arrhythmias in a patient's heart are disclosed. A source of antitachycardia pacing therapy and an electrode system including at least three electrodes for delivering the antitachycardia pacing therapy to the heart are provided. Circuitry and software for detecting a tachycardia having a site of focus in the heart and for determining the relative distances of the electrodes from the focus site are also provided. The three or more electrodes are connected to the source of antitachycardia pacing therapy based on the relative distances determined and in such a manner as to create a virtual electrode at the focus site upon delivery of the therapy to the heart.