摘要:
A cardiac rhythm management system selects one of multiple electrodes associated with a particular heart chamber based on a relative timing between detection of a depolarization fiducial point at the multiple electrodes, or based on a delay between detection of a depolarization fiducial point at the multiple electrodes and detection of a reference depolarization fiducial point at another electrode associated with the same or a different heart chamber. Subsequent contraction-evoking stimulation therapy is delivered from the selected electrode.
摘要:
This document discusses, among other things, systems, devices, and methods measure an impedance and, in response, adjust an atrioventricular (AV) delay or other cardiac resynchronization therapy (CRT) parameter that synchronizes left and right ventricular contractions. A first example uses parameterizes a first ventricular volume against a second ventricular volume during a cardiac cycle, using a loop area to create a synchronization fraction (SF). The CRT parameter is adjusted in closed-loop fashion to increase the SF. A second example measures a septal-freewall phase difference (PD), and adjusts a CRT parameter to decrease the PD. A third example measures a peak-to-peak volume or maximum rate of change in ventricular volume, and adjusts a CRT parameter to increase the peak-to-peak volume or maximum rate of change in the ventricular volume.
摘要:
A technique for determining a patient's hematocrit by an electrical impedance measurement is described. An implantable device may be configured to utilize the technique in order to assess a cardiac patient's fluid status. In order to determine the hematocrit, the electrical impedance of the blood is measured and mapped by a mapping function to a corresponding hematocrit value.
摘要:
A cardiac electro-stimulatory device and method for operating same in which stimulation pulses are distributed among a plurality of electrodes fixed at different sites of the myocardium in order to reduce myocardial hypertrophy brought about by repeated pacing at a single site and/or increase myocardial contractility. In order to spatially and temporally distribute the stimulation, the pulses are delivered through a switchable pulse output configuration during a single cardiac cycle, with each configuration comprising one or more electrodes fixed to different sites in the myocardium.
摘要:
A pacing system for providing optimal hemodynamic cardiac function for parameters such as ventricular synchrony or contractility (peak left ventricle pressure change during systole or LV+dp/dt), or stroke volume (aortic pulse pressure) using system for calculating atrio-ventricular delays for optimal timing of a ventricular pacing pulse. The system providing an option for near optimal pacing of multiple hemodynamic parameters. The system deriving the proper timing using electrical or mechanical events having a predictable relationship with an optimal ventricular pacing timing signal.
摘要:
A gene regulatory system detects ischemia events and is capable of delivering a biologic therapy in response to the detection of an ischemic event or the reception of a command. The biologic therapy protects the heart from ischemic damage by regulating the expression of an exogenously introduced gene product. In one embodiment, the gene regulatory system includes an implantable system that emits at least one gene regulatory signal in response to the detection of the ischemic event or the reception of the command. The gene regulatory signal directly or indirectly regulates gene expression of the gene product.
摘要:
Various system embodiments comprise a neural stimulator, a pulse generator, and a controller. The neural stimulator is adapted to generate a neural stimulation signal. The pulse generator is adapted to generate a pacing signal to provide myocardium pacing. The controller is adapted to control the neural stimulator and the pulse generator to provide a cardioprotective conditioning therapy. The conditioning therapy includes neural stimulation to elicit a parasympathetic response and myocardium pacing. Other aspects and embodiments are provided herein.
摘要:
Various system embodiments comprise a neural stimulator and a controller. The neural stimulator is adapted to generate a stimulation signal adapted to elicit sympathetic activity at a neural target. The controller is adapted to control the neural stimulator to provide a physical conditioning therapy. The controller is adapted to control the neural stimulator to intermittently elicit sympathetic activity at the neural target. Other aspects and embodiments are provided herein.
摘要:
A method and device for delivering multi-site ventricular pacing therapy in conjunction with parasympathetic stimulation for reducing ventricular wall stress. Such reduction in ventricular wall stress is useful in reversing or preventing the ventricular remodeling which can occur in heart failure patients.
摘要:
Various system embodiments comprise a neural stimulator and a controller. The neural stimulator is adapted to generate a stimulation signal adapted to elicit sympathetic activity at a neural target. The controller is adapted to control the neural stimulator to provide a physical conditioning therapy. The controller is adapted to control the neural stimulator to intermittently elicit sympathetic activity at the neural target. Other aspects and embodiments are provided herein.