摘要:
Methods for improving detection of arrhythmias by adaptively increasing arrhythmia detection intervals. One method includes increasing the V2V, the overall cardiac cycle length, thereby decreasing the pacing rate in the presence of ventricular safety paces (VSPs). Another method includes shortening the trigger interval following the atrial pace event, during which time the pacemaker will detect V-sense events, while leaving the A2V VSP interval unchanged, at the end of which any required VSP will be generated. In yet another method, the interval from A-pace to V-pace, the PAV interval, is shortened, while leaving the overall V2V cycle interval unchanged. This increases the ventricular to artial V2A interval, increasing the detection window for arthythmias. The PAV interval can be shortened in response to a recent history of VSP events.
摘要:
Devices, systems and methods are disclosed by which the blood pressure, nervous system activity, and neurohormonal activity may be selectively and controllably reduced by activating baroreceptors. An intravascularly implantable medical device may include a sleeve formed at least in part of an expandable member configured to be movably attachable about at least a portion of an outer surface of an expandable intravascular stent, and one or more electrodes disposed on the sleeve and coupled to a control system and configured to selectively activate baroreceptors within a wall of a vessel when the expandable intravascular stent is implanted within the vessel.
摘要:
Systems and methods provide baroreflex activation to treat or reduce pain and/or to cause or enhance sedation or sleep. Methods involve activating the baroreflex system to provide pain reduction, sedation, improved sleep or some combination thereof. Systems include at least one baroreflex activation device, at least one sensor for sensing physiological activity of the patient, and a processor coupled with the baroreflex activation device(s) and the sensor(s) for processing sensed data received from the sensor and for activating the baroreflex activation device. In some embodiments, the system is fully implantable within a patient, such as in an intravascular, extravascular or intramural location.
摘要:
Devices, systems and methods are described by which the blood pressure, nervous system activity, and neurohormonal activity may be selectively and controllably reduced by activating baroreceptors. A baroreceptor activation device is positioned near a baroreceptor, preferably a baroreceptor located in the carotid sinus. A control system may be used to modulate the baroreceptor activation device. The control system may utilize an algorithm defining a stimulus regimen which promotes long term efficacy and reduces power requirements/consumption. The baroreceptor activation device may utilize electrodes to activate the baroreceptors. The electrodes may be adapted for connection to the carotid arteries at or near the carotid sinus, and may be designed to minimize extraneous tissue stimulation.
摘要:
Devices, systems and methods provide baroreflex activation to prevent, or at least reduce the likelihood of occurrence of, cardiac arrhythmias. Various embodiments may additionally or alternatively promote recovery from arrhythmias. In one embodiment, a device for preventing or reducing the likelihood of occurrence of arrhythmias includes one or more baroreflex activation devices, one or more sensors coupled to the baroreflex activation device(s), and a processor for processing information from the sensor and activating and/or modulation the baroreflex activation device. Sensors, such as electrocardiogram devices, generally sense factors indicative of a potential, ensuing arrhythmia.
摘要:
Electrode structures for implantation include an electrode, an elastic backing attached to the electrode, and a sequestered drug on the backing or the electrode which is released to control and/or limit the growth of scar tissue. The elastic backing includes a tissue contacting side which contacts a tissue structure, and an exposed side away from the tissue contacting side. The electrode structure can be used to activate baroreceptors, and the backing is elastic and can stretch and retract with the tissue structure, for example the carotid sinus. The electrode and the sequestered drug can be positioned on the tissue contacting side so the drug is released near the electrode. The backing can be made from an insulating material and limit diffusion of the drug toward the exposed side, permitting scar tissue to grow near the exposed side to maintain positioning of the electrode.
摘要:
A system for stimulation, including an implantable pulse generator, a lead comprising an array body disposed at a distal end of the lead and a plurality of electrodes concentrically arranged on the array body, and a plurality of conductors, wherein one of the conductors is attached to each electrode and wherein the conductors are configured and arranged to couple the electrodes to the implantable pulse generator.
摘要:
A method and apparatus for stimulation of a baroreflex system of a patient is provided. A method comprises establishing a therapy regimen including at least one pulse which includes at least two phases. Each phase has a polarity which is different than that of the other phase. The baroreflex system of the patient is activated with at least one baroreflex activation device which is responsive to the therapy regimen.
摘要:
A programmable cardiac pacemaker pulse generator utilizing digital circuitry for controlling the provision of cardiac stimulating pulses. The pulse generator is capable of having the rate, the pulse width, the pulse amplitude, the refractory period, the sensitivity and the mode of operation programmed. In addition, the pulse generator can have the output inhibited and can respond to programming signals causing a threshold margin test to be performed, effects of closure of the reed switch overridden, a hysteresis function added and a high rate exceeding the normal upper rate limit programmed. Many of the programmable functions of the pulse generator can either be programmed on a permanent or a temporary basis. The pulse generator further includes means for signalling the acceptance of a programming signal, and means to reset the program acceptance circuit if extraneous signals are detected as programming signals. The program signal acceptance circuit performs several different checks on the detected programming signal including a parity check, an access code check and determining if the proper number of signals were transmitted within a given time. The timing circuit of the pulse generator includes a crystal clock oscillator and counter means for counting the clock pulses therefrom to determine the rate of the pacemaker. The pulse width of each pacemaker pulse is determined by using a volage controlled oscillator in place of the crystal oscillator to obtain energy compensation due to the battery voltage decreasing with time.
摘要:
Devices, systems and methods are described by which the blood pressure, nervous system activity, and neurohormonal activity may be selectively and controllably reduced by activating baroreceptors. A baroreceptor activation device is positioned near a baroreceptor, preferably a baroreceptor located in the carotid sinus. A control system may be used to modulate the baroreceptor activation device. The control system may utilize an algorithm defining a stimulus regimen which promotes long term efficacy and reduces power requirements/consumption. The baroreceptor activation device may utilize electrodes to activate the baroreceptors. The electrodes may be adapted for connection to the carotid arteries at or near the carotid sinus, and may be designed to minimize extraneous tissue stimulation.