Abstract: In one aspect, a computer-implemented method includes receiving a signal corresponding to impedance across a patient's chest cavity; filtering the signal using one or more filters that reduce noise and center the signal around a zero baseline; adjusting an amplitude of the filtered signal based on a threshold value; separating the amplitude-adjusted signal into component signals, where each of the component signals represents a frequency-limited band; detecting a fractional phase transition of a component signal of the component signals; selecting a dominant component signal from the component signals based on amplitudes of the component signals at a time corresponding to the detected fractional phase transition; determining a frequency of the dominant component signal at the time corresponding to the detected fractional phase transition; and determining a respiratory rate of the patient based on the determined frequency.

Abstract: In one aspect, a computer-implemented method includes receiving signals corresponding to wavelengths of light detected by an optical sensor placed in proximity to a patient's body, and for each received signal: separating the signal into an AC signal and a DC signal; separating the AC signal into component signals; analyzing the component signals through a fractional phase transformation to identify a desired component signal and harmonic signals associated with the desired component signal; smoothing the desired component signal, the harmonic signals, and the DC signal; and combining the smoothed desired component signal, the smoothed harmonic signals, and the smoothed DC signal to generate a modulation signal. A modulation ratio signal is generated based on the modulation signals derived from the signals, and a peripheral oxygen saturation (SpO2) of the patient's body is determined based on the modulation ratio signal.

Abstract: The present invention provides a system and method for representing quasi-periodic (“qp”) waveforms comprising, representing a plurality of limited decompositions of the qp waveform, wherein each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the qp waveform. These decompositions are stored into a data structure having a plurality of attributes. Optionally, these attributes are used to reconstruct the qp waveform, or patterns or features of the qp wave can be determined by using various pattern-recognition techniques. Some embodiments provide a system that uses software, embedded hardware or firmware to carry out the above-described method. Some embodiments use a computer-readable medium to store the data structure and/or instructions to execute the method.

Abstract: In one aspect, a computer-implemented method includes receiving a signal corresponding to impedance across a patient's chest cavity; filtering the signal using one or more filters that reduce noise and center the signal around a zero baseline; adjusting an amplitude of the filtered signal based on a threshold value; separating the amplitude-adjusted signal into component signals, where each of the component signals represents a frequency-limited band; detecting a fractional phase transition of a component signal of the component signals; selecting a dominant component signal from the component signals based on amplitudes of the component signals at a time corresponding to the detected fractional phase transition; determining a frequency of the dominant component signal at the time corresponding to the detected fractional phase transition; and determining a respiratory rate of the patient based on the determined frequency.

Abstract: In one aspect, a computer-implemented method includes receiving a signal corresponding to electrical activity of a patient's heart; separating the signal into component signals; detecting fractional phase transitions for each of the component signals; generating, at each of the detected fractional phase transitions for each of the component signals, a data object containing a time value and an amplitude value; for a set of consecutive data objects associated with a first component signal of the component signals, detecting a peak amplitude; for a set of consecutive data objects associated with a second component signal of the component signals, detecting a peak amplitude; determining that the peak amplitudes satisfy a first time; calculating a consolidated peak amplitude and a consolidated peak time; and in response to determining that the consolidated peak amplitude satisfies both an amplitude criterion and a second time criterion, providing an indication of a detected heartbeat.

Abstract: In one aspect, a computer-implemented method includes receiving signals corresponding to wavelengths of light detected by an optical sensor placed in proximity to a patient's body, and for each received signal: separating the signal into an AC signal and a DC signal; separating the AC signal into component signals; analyzing the component signals through a fractional phase transformation to identify a desired component signal and harmonic signals associated with the desired component signal; smoothing the desired component signal, the harmonic signals, and the DC signal; and combining the smoothed desired component signal, the smoothed harmonic signals, and the smoothed DC signal to generate a modulation signal. A modulation ratio signal is generated based on the modulation signals derived from the signals, and a peripheral oxygen saturation (SpO2) of the patient's body is determined based on the modulation ratio signal.

Abstract: A system and method for representing quasi-periodic waveforms, for example, representing a plurality of limited decompositions of the quasi-periodic waveform. Each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the quasi-periodic waveform. Data-structure attributes are created and used to reconstruct the quasi-periodic waveform. Features of the quasi-periodic wave are tracked using pattern-recognition techniques. The fundamental rate of the signal (e.g., heartbeat) can vary widely, for example by a factor of 2-3 or more from the lowest to highest frequency. To get quarter-phase representations of a component (e.g.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to a first electrode over a time period and generating a first time-frequency distribution corresponding to the first signal. The first time-frequency distribution includes a first dominant frequency value representation occurring at one or more first base frequencies. The processor is also capable of applying a filter to the first signal or derivatives thereof to determine whether the first dominant frequency value representation includes a single first dominant frequency value at a first base frequency or two or more first dominant frequency values at two or more base frequencies.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to a first electrode over a time period and generating a first time-frequency distribution corresponding to the first signal. The first time-frequency distribution includes a first dominant frequency value representation occurring at one or more first base frequencies. The processor is also capable of applying a filter to the first signal or derivatives thereof to determine whether the first dominant frequency value representation includes a single first dominant frequency value at a first base frequency or two or more first dominant frequency values at two or more base frequencies.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to a first electrode over a time period and generating a first time-frequency distribution corresponding to the first signal. The first time-frequency distribution includes a first dominant frequency value representation occurring at one or more first base frequencies. The processor is also capable of applying a filter to the first signal or derivatives thereof to determine whether the first dominant frequency value representation includes a single first dominant frequency value at a first base frequency or two or more first dominant frequency values at two or more base frequencies.

Abstract: A system and method for representing quasi-periodic waveforms, for example, representing a plurality of limited decompositions of the quasi-periodic waveform. Each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the quasi-periodic waveform. Data-structure attributes are created and used to reconstruct the quasi-periodic waveform. Features of the quasi-periodic wave are tracked using pattern-recognition techniques. The fundamental rate of the signal (e.g., heartbeat) can vary widely, for example by a factor of 2-3 or more from the lowest to highest frequency. To get quarter-phase representations of a component (e.g.

Abstract: A system and method for representing quasi-periodic waveforms, for example, representing a plurality of limited decompositions of the quasi-periodic waveform. Each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the quasi-periodic waveform. Data-structure attributes are created and used to reconstruct the quasi-periodic waveform. Features of the quasi-periodic wave are tracked using pattern-recognition techniques. The fundamental rate of the signal (e.g., heartbeat) can vary widely, for example by a factor of 2-3 or more from the lowest to highest frequency. To get quarter-phase representations of a component (e.g.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first electrode and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to the first electrode and a second signal corresponding to the second electrode. Collecting the first and second signals occurs over a time period. The processor is also capable of generating a first time-frequency distribution corresponding to the first signal, identifying a first dominant frequency value occurring at a first dominant frequency and a first time point, generating a second time-frequency distribution corresponding to the second signal, identifying a second dominant frequency value occurring at a second dominant frequency and a second time point and determining an attraction point.

Abstract: Medical devices and methods for making and using medical devices are disclosed. A method for removing an artifact of a biological reference signal present in a biological source signal may comprise sensing a biological reference signal with one or more electrodes and sensing a biological source signal, wherein the biological source signal comprises an artifact of the biological reference signal. The method may further comprise determining, based on the biological reference signal, the artifact of the biological reference signal and subtracting the artifact of the biological reference signal from the sensed biological source signal.

Abstract: Medical devices and methods for making and using medical devices are disclosed. A method for removing an artifact of a biological reference signal present in a biological source signal may comprise sensing a biological reference signal with one or more electrodes and sensing a biological source signal, wherein the biological source signal comprises an artifact of the biological reference signal. The method may further comprise determining, based on the biological reference signal, the artifact of the biological reference signal and subtracting the artifact of the biological reference signal from the sensed biological source signal.

Abstract: A system and method for representing quasi-periodic (“qp”) waveforms, for example, representing a plurality of limited decompositions of the qp waveform. Each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the qp waveform. Data-structure attributes are created and used to reconstruct the qp waveform. Features of the qp wave are tracked using pattern-ecognition techniques. The fundamental rate of the signal (e.g., heartbeat) can vary widely, for example by a factor of 2-3 or more from the lowest to highest frequency. To get quarter-phase representations of a component (e.g., lowest frequency “rate” component) that varies over time (by a factor of two to three) many overlapping filters use bandpass and overlap parameters that allow tracking the component's frequency version on changing quarter-phase basis.

Abstract: A system and method for representing quasi-periodic waveforms, for example, representing a plurality of limited decompositions of the quasi-periodic waveform. Each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the quasi-periodic waveform. Data-structure attributes are created and used to reconstruct the quasi-periodic waveform. Features of the quasi-periodic wave are tracked using pattern-recognition techniques. The fundamental rate of the signal (e.g., heartbeat) can vary widely, for example by a factor of 2-3 or more from the lowest to highest frequency. To get quarter-phase representations of a component (e.g.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first electrode and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to the first electrode and a second signal corresponding to the second electrode. Collecting the first and second signals occurs over a time period. The processor is also capable of generating a first time-frequency distribution corresponding to the first signal, identifying a first dominant frequency value occurring at a first dominant frequency and a first time point, generating a second time-frequency distribution corresponding to the second signal, identifying a second dominant frequency value occurring at a second dominant frequency and a second time point and determining an attraction point.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to a first electrode over a time period and generating a first time-frequency distribution corresponding to the first signal. The first time-frequency distribution includes a first dominant frequency value representation occurring at one or more first base frequencies. The processor is also capable of applying a filter to the first signal or derivatives thereof to determine whether the first dominant frequency value representation includes a single first dominant frequency value at a first base frequency or two or more first dominant frequency values at two or more base frequencies.

Abstract: A system and method for representing quasi-periodic waveforms, for example, representing a plurality of limited decompositions of the quasi-periodic waveform. Each decomposition includes a first and second amplitude value and at least one time value. In some embodiments, each of the decompositions is phase adjusted such that the arithmetic sum of the plurality of limited decompositions reconstructs the quasi-periodic waveform. Data-structure attributes are created and used to reconstruct the quasi-periodic waveform. Features of the quasi-periodic wave are tracked using pattern-recognition techniques. The fundamental rate of the signal (e.g., heartbeat) can vary widely, for example by a factor of 2-3 or more from the lowest to highest frequency. To get quarter-phase representations of a component (e.g.