VivaQuant products and services may be covered by one or more of the following patents.
Representative claims for certain issued patents are also presented below*.   The following is a partial list of our patents.

Patent Number Title Representative Independent Claim
8,632,465
[PDF]		 Physiological Signal Denoising A method for computing a denoised physiological signal from an input signal including a desired pseudo-periodic physiological signal and noise, the method comprising:

  • decomposing the input signal from a first domain into subcomponents of the input signal and a second domain that is different than the first domain;
  • identifying target subcomponents of the input signal that are associated with the desired physiological signal based upon the time-based distribution of the subcomponents; and
  • reconstructing a denoised physiological signal in the first domain from at least two of the identified target subcomponents.
9,294,074
[PDF]		 Physiological Signal Denoising A method for computing a denoised ECG signal from an input signal including an ECG signal and noise, the method comprising:

  • identifying the location of a QRS complex of a cardiac cycle in the input signal;
  • identifying a first time window in the cardiac cycle that includes the QRS complex;
  • identifying a second time window in the cardiac cycle that does not include the QRS complex; and
  • removing a band of frequencies from the second time window.
8,478,389
[PDF]		 System for processing physiological data An apparatus comprising:

  • a computer circuit configured and arranged to identify at least one cycle within electrocardiogram signal,
  • identify feature point within a subsegment of the at least one cycle by decomposing set electrocardiogram signal into subcomponents, computing an emphasis signal using one or more subcomponents that together contain at least a majority of the energy of a signal wave within the subsegment, and
  • evaluating an emphasis signal to identify the feature point, and
  • compute a validity characteristic of the feature point based upon at least one of the estimated signal energy an estimated noise energy within the subsegment.
9,339,202
[PDF]		 System for processing physiological data A patient-worn apparatus for recording an ECG from the patient, the apparatus comprising:

  • a first circuit configured and arranged to digitize an ECG signal obtained from the patient via at least two ECG leads; and
  • a computing circuit connected to the first circuit to receive the digitized ECG signal, the computing circuit being configured and arranged to decompose the digitized ECG signal into subcomponents, compute a statistical variance of the subcomponents over a time interval, and determine if one of the at least two ECG leads is disconnected from the patient based upon the statistical variance of the subcomponents.
8,433,395
[PDF]		 System for automatic measurement of cardiac intervals and extraction of repolarization activity of an ECG A method for providing a repolarization signal for a cardiac cycle of an ECG signal, the method comprising:

  • identifying the location of a QRS complex and a cardiac cycle;
  • using the identified location of the QRS complex, identifying T-wave onset and offset points;
  • using the T-wave onset and offset points to respectively define the start and end of the repolarization signal for the cycle; and
  • in a computer circuit, determining a noise characteristic of the ECG signal in a time window spanning from about the start to about the end of the repolarization signal, and providing the repolarization signal as an output, based upon the determined noise characteristic.
9,050,007
[PDF]		 System for automatic measurement of cardiac intervals and extraction of repolarization activity of an ECG An apparatus for providing a time series of beat-to-beat QT interval values from a digitized ECG signal of an ambulatory subject, the apparatus comprising:

  • a circuit-based computer configured and arranged with executable instructions to identify the location of a QRS complex and a Q-wave onset point of a cardiac cycle of the ECG signal;
  • determine a first time window of the cardiac cycle in which to search for a T-wave offset point for a T-wave in the cardiac cycle, based upon one of the identified location of the QRS complex and the identified location of the Q-wave onset point;
  • identify the T-wave offset point within the first time window;
  • compute a QT interval value using the identified Q-wave onset point of the QRS complex and the identified T-wave offset point, and
  • provide the QT interval value in a time series of beat-to-beat QT interval values, based upon a noise characteristic of the digitized ECG signal in a second time window that includes at least a portion of the T-wave.
8,688,202
[PDF]		 Determining cardiac risk An apparatus comprising:

  • at least two ECG sensing electrodes configured and arranged to adhere to remote locations on a patient and to sense ECG signals from the patient;
  • a digitize circuit configured and arranged to digitize ECG signals to provide digitized ECG signal;
  • a computing circuit configured and arranged to process the digitized ECG signals by reducing the in band noise as measured by the ANSI/AAMI EC 57:1998 standard by at least 20 DB with a quality of signal reconstruction of > 95%;
  • a housing that houses a digitizing circuit and a computing circuit;
  • a fastener configured and arranged to mechanically fasten the housing to a first one of the ECG sensing electrodes and to electrically couple the first one of the ECG sensing electrodes to the digitizing circuit; and
  • for each additional one of the at least two ECG sensing electrodes that is in addition to the first one of the ECG sensing electrodes, a flexible insulating lead wire configured and arranged to couple the additional ECG sensing electrode to the digitizing circuit.
9,072,438
[PDF]		 Determining cardiac risk A method for computing a cardiac-based metric for use as a predictor of cardiac risk, the method comprising:

  • for each of a plurality of cardiac cycles of a subject, identifying the end of a mechanical systole based upon an acoustical vibration associated with closure of an aortic valve during the cardiac cycle; and
  • computing the cardiac-based metric based upon, for each of the plurality of cardiac cycles, a time difference between the end of the mechanical systole and the end of an electrical systole of an electrocardiogram (ECG) signal for the cardiac cycle.
9,008,762
[PDF]		 Determining cardiac risk A method comprising:

  • identifying a plurality of cardiac cycles in an electrical signal representative of an electrocardiogram (ECG) from a subject;
  • for each of the plurality of cardiac cycles, identifying T-wave offset of the ECG, and identifying a segment of an acoustical vibration representative of heart sounds from the subject, based upon a T-wave offset time of a corresponding ECG synchronized with the heart sounds;
  • constructing an array of the identified segments from each of the plurality of cycles;
  • computing heart sound and noise components of the acoustical vibration using blind source separation; and
  • detecting the presence of a heart sound based upon energy in the heart sound components and the noise components.
9,314,181
[PDF]		 Method and apparatus for detection of heartbeat characteristics A method comprising:

  • computing a time series of inter-beat intervals from a recording of activity of a beating heart;
  • decomposing the time series into subcomponents;
  • computing and envelope of at least one of the subcomponents; and detecting the presence of atrial fibrillation (AF) based upon characteristics of the envelope that are indicative of AF.
9,408,549
[PDF]		 Detecting fiducial points in physiological signals A method for identifying a QRS complex in an electrocardiogram (ECG), the method comprising:

  • decomposing the ECG into subcomponents;
  • selecting a subset of the subcomponents based upon a degree of overlap of spectral energy, in at least one of the subcomponents, with expected spectral energy of the QRS complex of the ECG;
  • combining at least two of the subcomponents in the subset;
  • comparing the combined subcomponents to a threshold; and
  • identifying the location of the QRS complex in the ECG based on the comparing.
9,492,096
[PDF]		 ECG sensing apparatuses systems and methods An apparatus comprising:

  • first and second electrodes configured and arranged to sense ECG signals from a subject; and
  • an circuitry including: a digitizing circuit configured and arranged to receive and digitize the ECG signals sensed by the electrodes;
  • an audio circuit including a microphone configured and arranged to capture voice sounds from the subject traveling through air, the audio circuit being configured and arranged to convert the captured voice sounds into electrical audio signals that can be reproduced for regenerating the voice sounds and therein providing audibly discernable speech;
  • a processing circuit configured and arranged with the electrodes and digitizing circuit to digitize the ECG signals and to process each digitized ECG signal by at least one of removing noise from the digitized ECG signal, storing the digitized ECG signal in a memory circuit, detecting a QRS complex in the digitized ECG signal, evaluating quality of the digitized ECG signal, and detecting arrhythmia in the digitized ECG signal;
  • an input circuit configured and arranged to receive an input from the subject and including at least one manual switch configured and arranged to provide the input in response to the subject manually activating the at least one switch, the processing circuit and audio circuit being respectively configured and arranged with the input circuit to initiate recording of at least one of the ECG signals and the sound in response to the input; and
  • a communication circuit configured and arranged to communicate the processed digitized ECG signals and the audio signals and the audio signals for receipt by an external device.
9,414,786
[PDF]		 ECG sensing with noise filtering An apparatus comprising:

  • at least two electrodes configured and arranged to sense an ECG signal; digitizing circuitry communicatively coupled to the at least two electrodes and configured and arranged to generate a digitized ECG signal from the ECG signal sensed via the electrodes; and
  • a computing circuit coupled to the digitizing circuitry and configured and arranged to generate a denoised ECG signal from the digitized ECG signal, the denoised ECG signal having, relative to the digitized ECG signal, an improved signal-to-noise ratio of at least 15 dB as measured using the ANSI EC 57 standard, and a quality of signal reconstruction greater than 95%.
9,414,758
[PDF]		 Apparatus, system and methods for sensing and processing physiological signals A skin contacting electrode apparatus for measuring ECG signals, the apparatus comprising:

  • an electrically conductive material; and
  • conductive flexible microfibers extending from the conductive material, and configured and arranged to protrude into pores in skin and sense an ECG signal from inner surfaces of the pores, below a surface layer of the skin in which the pores reside.

* The information listed above may be subject to inaccuracies due to typographical errors and/or other relevant matters. For additional information regarding these patents, please click on the link to the full patent or examine the patent at www.USPTO.gov.