摘要:
A computer-assisted method for quantitatively characterizing atrial fibrillation in a patient includes recording time series of bipolar atrial fibrillation signals at multiple sites in a patient's atria using two or more electrodes, calculating a similarity index vector by a computer system based on the bipolar atrial fibrillation signal between a first site and its neighboring sites, constructing an similarity-index vector field based on similarity-index vectors at different sites, calculating Curl and Divergence of the similarity-index vector field, calculating Rotor Identification using Curl and Divergence, calculating Focal Identification using Divergence, and determining one or more critical regions in the patient's atria if Rotor Identification is above a first predetermined threshold and Focal Identification is above a second predetermined threshold.
摘要:
A computer-assisted method for quantitative characterization and treatment of ventricular fibrillation includes preprocessing a time series of an atrial fibrillation signal obtained from a patient, segmenting the time series of the AF signal into activation segments by the computer system, obtaining local activation waveforms (LAW) from the activation segments, determining degrees of similarity between the LAWs, and identifying one or more critical regions in the patient's atria if the LAWs have degrees of similarity exceeding a first threshold value.
摘要:
A computer-assisted method for quantitative characterization and treatment of ventricular fibrillation includes acquiring a time series of a ventricular fibrillation (VF) signal using a probe from a patient experiencing VF, subtracting the mean from the time series of the VF signal, calculating a cumulative VF signal after the mean is subtracted from the time series of the VF signal, segmenting the cumulative VF signal by a plurality of sampling boxes, calculating the root-mean-square of the cumulative VF signal as a function of the sampling box size , extracting an exponent of the root-mean-square of the cumulative VF signal as a function of the sampling box size, applying electrical defibrillation to the patient if the exponent is below a predetermined value, and applying cardiopulmonary resuscitation (CPR) to the patient if the exponent is above a predetermined value.
摘要:
A method for dynamic cerebral autoregulation (CA) assessment includes acquiring a blood pressure (BP) signal having a first oscillatory pattern from a first individual, acquiring a blood flow velocity (BFV) signal having a second oscillatory pattern from the first individual, decomposing the BP signal into a first group of intrinsic mode functions (IMFs), decomposing the BFV signal into a second group of IMFs, determining dominant oscillatory frequencies in the first group of IMFs, automatically selecting a first characteristic IMF from the first group of IMFs that has its associated dominant oscillatory frequency in a predetermined frequency range, automatically selecting a second characteristic IMF from the second group of IMFs, calculating a time sequence of instantaneous phase difference between the first characteristic IMF and the second characteristic IMF, computing an average of the instantaneous phase difference in the time sequence, and identifying a pathological condition in the first individual.
摘要:
A computer-assisted method for quantitative analysis of respiratory sinus arrhythmia (RSA) includes obtaining a time series of a cardiac interval signal from an individual, obtaining a time series of a respiratory signal from the individual; decomposing the cardiac interval signal into a first group of ensemble empirical modes; obtaining, by a computer system, a time series of RSA instantaneous amplitude from at least one of the first group of ensemble empirical modes; decomposing the respiratory signal into a second group of ensemble empirical modes; obtaining a time series of respiratory instantaneous phase from the one of the second group of ensemble empirical modes; determining respiratory period from the time series of the respiratory instantaneous phase; and quantifying RSA in the individual according to a dependence of the RSA instantaneous amplitude on the respiratory period.
摘要:
A method for detecting sleep-disordered breathing (SDB) includes acquiring a time sequence of a physiological signal from an individual, wherein the time sequence of the physiological signal includes a oscillatory pattern, computing an oscillatory interval signal using the time sequence of the physiological signal, decomposing the oscillatory interval signal into a plurality of ensemble empirical modes, selecting one of the plurality of ensemble empirical modes, calculating at least one of average amplitude or standard deviation of the instantaneous frequency in the selected ensemble empirical mode; and identifying SDB using at least one of the average amplitude or the standard deviation of the instantaneous frequency.
摘要:
A computer-assisted method for quantitative characterization and treatment of ventricular fibrillation includes acquiring a time series of a ventricular fibrillation (VF) signal using a probe from a patient experiencing VF, subtracting the mean from the time series of the VF signal, calculating a cumulative VF signal after the mean is subtracted from the time series of the VF signal, segmenting the cumulative VF signal by a plurality of sampling boxes, calculating the root-mean-square of the cumulative VF signal as a function of the sampling box size , extracting an exponent of the root-mean-square of the cumulative VF signal as a function of the sampling box size, applying electrical defibrillation to the patient if the exponent is below a predetermined value, and applying cardiopulmonary resuscitation (CPR) to the patient if the exponent is above a predetermined value.
摘要:
A method for dynamic cerebral autoregulation (CA) assessment includes acquiring a blood pressure (BP) signal having a first oscillatory pattern from a first individual, acquiring a blood flow velocity (BFV) signal having a second oscillatory pattern from the first individual, decomposing the BP signal into a first group of intrinsic mode functions (IMFs), decomposing the BFV signal into a second group of IMFs, determining dominant oscillatory frequencies in the first group of IMFs, automatically selecting a first characteristic IMF from the first group of IMFs that has its associated dominant oscillatory frequency in a predetermined frequency range, automatically selecting a second characteristic IMF from the second group of IMFs, calculating a time sequence of instantaneous phase difference between the first characteristic IMF and the second characteristic IMF, computing an average of the instantaneous phase difference in the time sequence, and identifying a pathological condition in the first individual.
摘要:
A computer-assisted method for quantitatively characterizing atrial fibrillation in a patient includes recording time series of bipolar atrial fibrillation signals at multiple sites in a patient's atria using two or more electrodes, calculating a similarity index vector by a computer system based on the bipolar atrial fibrillation signal between a first site and its neighboring sites, constructing an similarity-index vector field based on similarity-index vectors at different sites, calculating Curl and Divergence of the similarity-index vector field, calculating Rotor Identification using Curl and Divergence, calculating Focal Identification using Divergence, and determining one or more critical regions in the patient's atria if Rotor Identification is above a first predetermined threshold and Focal Identification is above a second predetermined threshold.
摘要:
A computer-assisted method for quantitative characterization and treatment of ventricular fibrillation includes preprocessing a time series of an atrial fibrillation signal obtained from a patient, segmenting the time series of the AF signal into activation segments by the computer system, obtaining local activation waveforms (LAW) from the activation segments, determining degrees of similarity between the LAWs, and identifying one or more critical regions in the patient's atria if the LAWs have degrees of similarity exceeding a first threshold value.