摘要:
An impedance monitor for discerning edema through evaluation of respiratory rate. Preferred embodiment includes edema monitor and trigger to initiate diagnostic reporting or corrective action when activated. Recording of Long Term Average and Short Term Average values for secondary edema measure based on DC signal level are described as are methods and apparatus for removing unwanted recurring noise.
摘要:
An impedance monitor for discerning edema through evaluation of respiratory rate. Preferred embodiment includes edema monitor and trigger to initiate diagnostic reporting or corrective action when activated. Recording of Long Term Average and Short Term Average values for secondary edema measure based on DC signal level are described as are methods and apparatus for removing unwanted recurring noise.
摘要:
A method and apparatus for automatic determination of a pacemaker patient's pacing stimulation threshold. Circuitry is provided in a pacemaker for obtaining a signal reflecting cardiac impedance, which is known to reliably reflect certain aspects of cardiac function. Circuitry is also provided for monitoring the cardiac impedance waveform during a predetermined capture detect window following delivery of stimulating pulses. One or more values are derived which characterize the morphology of the impedance waveform during the capture detect window associated with each stimulation pulse delivered. These values are compared to predetermined control values in order to assess whether a stimulation pulse has achieved cardiac capture. The assessment of whether cardiac capture has been achieved is also based partly upon the conventional sensing of atrial and/or ventricular cardiac signals occurring during the capture detect window. In one embodiment of the invention, the control values against which impedance waveform characterization values are compared are obtained by delivering a series of stimulation pulses having sufficient energy to ensure that capture is achieved, and by monitoring the impedance waveform during delivery of these pulses.
摘要:
A method and apparatus for automatic determination of a pacemaker patient's pacing stimulation threshold. Circuitry is provided in a pacemaker for obtaining a signal reflecting cardiac impedance, which is known to reliably reflect certain aspects of cardiac function. Circuitry is also provided for monitoring the cardiac impedance waveform during a predetermined capture detect window following delivery of stimulating pulses. One or more values are derived which characterize the morphology of the impedance waveform during the capture detect window associated with each stimulation pulse delivered. These values are compared to predetermined control values in order to assess whether a stimulation pulse has achieved cardiac capture. The assessment of whether cardiac capture has been achieved is also based partly upon the conventional sensing of atrial and/or ventricular cardiac signals occurring during the capture detect window. In one embodiment of the invention, the control values against which impedance waveform characterization values are compared are obtained by delivering a series of stimulation pulses having sufficient energy to ensure that capture is achieved, and by monitoring the impedance waveform during delivery of these pulses.
摘要:
A method and apparatus for automatic determination of a pacemaker patient's pacing stimulation threshold. Circuitry is provided in a pacemaker for obtaining a signal reflecting cardiac impedance, which is known to reliably reflect certain aspects of cardiac function. Circuitry is also provided for monitoring the cardiac impedance waveform during a predetermined capture detect window following delivery of stimulating pulses. One or more values are derived which characterize the morphology of the impedance waveform during the capture detect window associated with each stimulation pulse delivered. These values are compared to predetermined control values in order to assess whether a stimulation pulse has achieved cardiac capture. The assessment of whether cardiac capture has been achieved is also based partly upon the conventional sensing of atrial and/or ventricular cardiac signals occurring during the capture detect window. In one embodiment of the invention, the control values against which impedance waveform characterization values are compared are obtained by delivering a series of stimulation pulses having sufficient energy to ensure that capture is achieved, and by monitoring the impedance waveform during delivery of these pulses.
摘要:
In an implantable medical device that provides atrial and ventricular pacing in an atrial-based pacing mode, longer periods of time are permitted for intrinsic AV conduction to occur. By monitoring the patient's AV delay under these circumstances, useful information is obtained that can be correlated to other patient conditions or symptoms.
摘要:
A medical method, device, and system are provided, including advancing an ablation element of a medical device into contact with tissue to be treated, selecting a power level of energy to ablate the tissue, delivering energy at the selected power level to the ablation element, determining whether the ablation element is in continuous contact with the tissue, and reducing the selected power level when the ablation element ceases to be in continuous contact with the tissue.
摘要:
A medical method, device, and system are provided, including advancing an ablation element of a medical device into contact with tissue to be treated, selecting a power level of energy to ablate the tissue, delivering energy at the selected power level to the ablation element, determining whether the ablation element is in continuous contact with the tissue, and reducing the selected power level when the ablation element ceases to be in continuous contact with the tissue.
摘要:
A method and system for detecting a short circuit during a radiofrequency ablation procedure. The method includes measuring an impedance of a pair of electrodes coupled to a treatment assembly of a medical device. Radiofrequency ablation energy is transmitted between the pair of electrodes. The transmission of radiofrequency ablation energy between the pair of electrodes is terminated when after a predetermined period of time the measured impedance in either of the electrodes in the pair of electrodes is below a predetermined threshold impedance value. An alert is generated indicating a short circuit between the pair of electrodes.
摘要:
A method of ablating an epicardial tissue region, including positioning a medical device adjacent the epicardial tissue region, the medical device having a first electrode, a second electrode, and a third electrode located in between the first and second electrodes; delivering an irrigation fluid to the tissue region; and ablating at least a portion of the tissue region by sequentially activating the third electrode in a monopolar radiofrequency delivery mode and activating the first and second electrodes in a bipolar radiofrequency delivery mode.