Abstract: Embodiments include methods, systems and computer program products for monitoring a person for a traumatic brain injury. Aspects include monitoring a gait of the user with one or more accelerometers embedded in the uniform and analyzing, by a processor, one or more characteristics of the gait of the user. Aspects also include determining whether the one or more characteristics of the gait indicate that the user may have suffered the traumatic brain injury and creating an alert that the user of the helmet may have suffered the traumatic brain injury.

Abstract: A cardiac lead system is provided. The lead is placed epicardially through the transverse pericardial sinus with integrated curvatures to prevent the lead from slipping out of the transverse pericardial sinus. Interaction with multiple chambers of the heart is facilitated in a single lead, without anchors that embed into the heart wall. Multiple electrodes can be grouped over each targeted heart area to ensure adequate electrical contact.

Abstract: Methods and devices are provided for managing anti-tachycardia pacing therapy delivered by an implantable medical device (IMD). The methods and devices detect events from cardiac signals sensed at electrodes of the IMD. The cardiac signals represent a ventricular tachycardia (VT) episode that includes at least a select number of VT events having a corresponding VT cycle length. The methods and devices analyze the VT cycle length to define an anti-tachycardia pacing (ATP) therapy that includes a first coupling interval and deliver a first ATP pulse that is spaced the first coupling interval after a reference refractory VT event sensed at the electrodes. The methods and devices deliver a second ATP pulse following the first ATP pulse by a non-stimulation segment that is at least one and three-quarters (1.75) times a projected VT cycle length.

Abstract: Embodiments include methods, systems and computer program products for monitoring a person for a traumatic brain injury. Aspects include monitoring a gait of the user with one or more accelerometers embedded in the uniform and analyzing, by a processor, one or more characteristics of the gait of the user. Aspects also include determining whether the one or more characteristics of the gait indicate that the user may have suffered the traumatic brain injury and creating an alert that the user of the helmet may have suffered the traumatic brain injury.

Abstract: A system is provided for displaying heart graphic information relating to sources and source locations of a heart disorder to assist in evaluation of the heart disorder. A heart graphic display system provides an intra-cardiogram similarity (“ICS”) graphic and a source location (“SL”) graphic. The ICS graphic includes a grid with the x-axis and y-axis representing patient cycles of a patient cardiogram with the intersections of the patient cycle identifiers indicating similarity between the patient cycles. The SL graphic provides a representation of a heart with source locations indicated. The source locations are identified based on similarity of a patient cycle to library cycles of a library cardiogram of a library of cardiograms.

Abstract: An implantable cardioverter defibrillator (ICD) performs a method that includes determining whether first criteria for detecting a ventricular tachyarrhythmia are met by a cardiac electrical signal. The ICD determines features from cardiac signal segment of a group of cardiac signal segments and determines whether a first portion of the features satisfy monomorphic waveform criteria and determines whether a second portion of the features satisfy supraventricular beat criteria. The ICD determines whether second criteria for detecting the ventricular tachyarrhythmia are met and withholds detecting of the ventricular tachyarrhythmia in response to the monomorphic waveform criteria and the supraventricular beat criteria being met.

Abstract: A system for assessing performance of a procedure comprises a tissue model or a tool comprising assessment indicators applied thereto, one or more image-capturing devices for capturing one or more assessment images of the assessment indicators while or after a user performs the medical procedure, and a processor configured to analyze the assessment indicators in the one or more assessment images and provide feedback to the user. A system can also comprise a tissue model, one or more image-capturing devices each configured to capture one or more images of the tissue model, and a processor configured to analyze the one or more images from the one or more image-capturing devices to determine a deformation of the tissue model and determine a force exerted on the tissue model based on the determined deformation of the tissue model.

Abstract: A medical system for providing a defibrillation therapy to a patient includes a cardiac monitoring device (CMD) configured to sense and record physiological data indicative of the patient's cardiac function. The CMD includes a communication component. The system also includes an external therapy device configured to deliver defibrillation therapy, and configured to be positioned external to and supported by the patient. The external therapy device includes an external therapy device communication component. The CMD communication component and the external therapy device communication component are configured to operatively couple the CMD and the external therapy device to one another, so as to work as a system to detect and treat fibrillation.

Abstract: Methods, systems and devices for providing cardiac resynchronization therapy (CRT) to a patient using a leadless cardiac pacemaker (LCP) and an extracardiac device (ED). The system is configured to identify atrial events to use as timing markers for the LCP to deliver CRT, and further to determine whether the timing markers are incorrectly sensed and to make adjustment or call for re-initialization as needed.

Abstract: The present disclosure provides systems and methods for automatically determining pace and sense configurations for an implantable cardiac device. A method of operating an implantable cardiac device includes automatically determining, during a detection phase, a pace and sense configuration for the implantable cardiac device based on a plurality of first impedance measurements. The method further includes confirming, during a confirmation phase, the pace and sense configuration based on a plurality of second impedance measurements, and operating the implantable cardiac device in accordance with the pace and sense configuration.

Abstract: Compositions and methods for treating various cardiovascular disorders include targeted delivery of glutamate for impairing a targeted portion of the autonomic nervous system (ANS). Targeted delivery may be via direct injection into the targeted portion of the ANS or via vascular injection of magnetically-targetable nanoparticles.

Abstract: This disclosure describes, among other embodiments, systems and related methods for selecting electrode combinations to be used during nerve pacing procedures. A first set of electrode combinations of a nerve pacing system, such as a phrenic nerve pacing system for diaphragm activation, may be mapped (or tested) to determine the location of the electrode combinations relative to a target nerve. Once the general location of the target nerve is known, a more localized second set of electrode combinations may be tested to determine the most suitable electrode combinations for nerve stimulation. At various stages of the mapping process, electrode combinations that are non-optimal may be discarded as candidates for use in a nerve pacing procedure. The systems and methods described herein may allow for the selection of electrode combinations that are most suitable for stimulation of the left and right phrenic nerves during diaphragm pacing.

Abstract: A method and apparatus for monitoring a cardiovascular pressure signal in a medical device that includes determining whether the sensed pressure signal is greater than a first pressure threshold, determining a first metric of the pressure signal in response to the sensed pressure signal being greater than the first pressure threshold, determining whether the sensed pressure signal is greater than a second pressure threshold not equal to the first pressure threshold, determining a second metric of the pressure signal in response to the sensed pressure signal being greater than the first pressure threshold, and determining at least one of a systolic pressure or a diastolic pressure, wherein the at least one of a systolic pressure or a diastolic pressure is determined based on the first metric in response to the pressure signal not being greater than the second threshold, and based on the second metric in response to the pressure signal being greater than the second threshold.

Abstract: Apparatus, systems and methods are provided for prevention and/or remediation of cardiac arrhythmias, e.g. optimizing anti-tachycardia pacing (ATP) algorithms. More particularly, implantable devices are provided that measure and treat cardiac arrhythmias. By monitoring the ATP attempt from additional electrodes, far-field morphology analyzes, and/or measuring the return interval from a failed ATP attempt; the devices may estimate when entrainment has occurred, the amount of delay within the reentrant tachycardia, and/or tachycardia termination/acceleration. These variables and occurrences can be used to optimize the first and/or subsequent ATP attempts. Furthermore, other exemplary embodiments describe methods to integrate electrical restitution properties into the design of ATP pacing algorithms to facilitate tachycardia termination.

Abstract: This document discusses, among other things, systems and methods to enable physician labels on a remote server and use labels to verify and improve algorithm results. A method comprises using patient data in an automated analysis to obtain a result; receiving a message from the user, wherein the message is related to the result; and using at least a portion of the message to automatically modify the analysis.

Abstract: The present disclosure relates to a wearable monitor device and methods and systems for using such a device. In certain embodiments, the wearable monitor records cardiac data from a mammal and extracts particular features of interest. These features are then transmitted and used to provide health-related information about the mammal.

Abstract: A method and medical device for adjusting a blanking period that includes sensing cardiac signals from a plurality of electrodes, the plurality of electrodes forming a plurality of sensing vectors, determining whether to adjust a blanking period during a first operating state, advancing from the first operating state to a second operating state in response to the sensed cardiac signals, determining, while in the second operating state, whether the blanking period was adjusted while in the first operating state, and adjusting the blanking period while in the second operating state in response to the blanking period being adjusted while in the first operating state.

Abstract: The present disclosure provides systems and methods for providing temporary induced dyssynchrony (TID) therapy to patients with atrial tachycardia. An implantable cardiac device includes a pulse generator coupled to a plurality of electrodes, and a controller communicatively coupled to the pulse generator and configured to cause the pulse generator to apply TID therapy to a patient's heart via the plurality of electrodes, determine that the patient's heart is experiencing atrial tachycardia, and adjust at least one parameter of the TID therapy based on the determination.

Abstract: Embodiments include a system for determining cardiovascular information for a patient. The system may include at least one computer system configured to receive patient-specific data regarding a geometry of the patient's heart, and create a three-dimensional model representing at least a portion of the patient's heart based on the patient-specific data. The at least one computer system may be further configured to create a physics-based model relating to a blood flow characteristic of the patient's heart and determine a fractional flow reserve within the patient's heart based on the three-dimensional model and the physics-based model.

Abstract: Embodiments of the present disclosure describe methods of adaptive arrhythmia detection comprising monitoring ECG signals of a patient via a patient medical device, detecting and capturing ECG segments based on a heart rate threshold and an initial sensitivity level associated with the heart rate threshold; and adjusting the sensitivity level based on previously captured ECG segments. Embodiments of the present disclosure further describe patient medical devices comprising one or more electrodes and sensing circuitry for monitoring ECG signals of a patient; and a processing module configured to receive the monitored ECG signal, wherein the processing module detects and captures ECG segments based on a plurality of heart rate thresholds and one or more sensitivity levels associated with each of the heart rate thresholds, and adjusts at least one of the one or more sensitivity levels associated with each of the heart rate thresholds.

Abstract: An implantable cardioverter defibrillator (ICD) receives a cardiac electrical signal by a sensing circuit while operating in a sensing without pacing mode and detects asystole based on the cardiac electrical signal. The ICD determines, in response to detecting the asystole, if asystole backup pacing is enabled, and automatically switches to a temporary pacing mode in response to the asystole backup pacing being enabled. Other examples of detecting asystole and providing a response to detecting asystole by the ICD are described herein.

Abstract: Systems and methods for model-based optimization of spinal cord stimulation electrodes and devices are disclosed. According to an aspect a method includes providing a patient-specific electroanatomical model including the spine, spinal cord, and a map of target neural elements and non-target neural elements. The method also includes using model electrodes to stimulate the target neural elements. Further, the method includes determining differences in activation thresholds between the target neural elements and the non-target neural elements in a plurality of different configurations of the model electrodes. The method also includes generating an optimal spinal cord stimulation electrode configuration based on the determined differences in activation thresholds.

Abstract: In general, the disclosure describes techniques for providing conditional electrical stimulation to a patient for pelvic health. An implantable medical device (IMD) may adjust the delivery cycle of the electrical stimulation applied to a patient in response to receiving a delivery cycle parameter associated with one or more of the following: a time in a time schedule, a control device output from a control device, and physiological information from a physiological information sensing device. As an example, the IMD may monitor a status of one or more inputs of the IMD and adjust the delivery cycle of the electrical stimulation applied to the patient based on the status of the input(s).

Abstract: A method to provide electrical stimulation therapy to stabilize ventricular rate of a heart during episodes of atrial fibrillation. The stimulation therapy may be a plurality of stimulation pulses delivered to the AV node during the AV node refractory period following the sensing of an atrial event.

Abstract: The present invention provides apparatus and methods for determining the occurrence of a QRS complex in ECG data. According to an aspect of the present invention, an apparatus is proposed for determining the occurrence of a QRS complex in ECG data by utilizing a first, second and third set of ECG data that are acquired by respectively electrode leads II, V4 and V5 and by determining whether a QRS complex has been detected within the predefined temporal window in at least two of the first, second and third sets of ECG data. According to another aspect of the present invention, an apparatus is proposed for determining the occurrence of a QRS complex in ECG data by utilizing three sets of ECG data whose signal quality values V are the smallest three of the first to twelfth sets of ECG data that are acquired by respectively the standard 12 electrode leads and by determining whether a QRS complex has been detected within the predefined temporal window in at least two of the three sets of ECG data.

Abstract: Multi-modal stimulation therapy may be utilized in which two or more stimulation therapies having different stimulation parameters may be delivered to a single patient. This can preferentially stimulate different nerve fiber types and drive different functional responses in the target organs. The stimulation parameters that may vary between the different stimulation therapies include, for example, pulse frequency, pulse width, pulse amplitude, and duty cycle.

Abstract: A hybrid model and diagnostic process for atrial fibrillation is provided. The present invention includes performing a combination of tests including an electrocardiogram signal analysis and a systolic pressure test. The results of the tests produce biomarkers for early detection of atrial fibrillation as well as for evaluating the severity of the disease.

Abstract: The present disclosure relates to cardiac evoked response detection and, more particularly, reducing polarization effects in order to detect an evoked response following delivery of a stimulation pulse. An implantable medical device (IMD) is configured to deliver a ventricular pacing pulse. A signal is sensed in response to the ventricular pacing stimulus. A window is placed over the sensed signal to obtain a set of data from the signal after a paced event. The set of data extracted from the sensed signal comprises a maximum amplitude, a maximum time associated with the maximum amplitude, a minimum amplitude, and a minimum time associated with the minimum amplitude. Responsive to processing the extracted data, the window is delayed to avoid polarization effects. A determination is then made as to whether the ventricular pacing stimulus is capturing the paced ventricle in response to determining whether the maximum time is greater than the minimum time.

Abstract: Apparatus and methods for generating an induction waveform for performing threshold testing in an implantable medical device are disclosed. Such tests may be performed during the implant procedure, or during a device checkup procedure, or routinely during the lifetime of the device. The threshold test may include induction of an arrhythmia (such as ventricular fibrillation) followed by delivery of therapy at various progressively-increasing stimulation parameters to terminate the arrhythmia. As such, the capability to induce fibrillation within the device is desired. Induction of the arrhythmias may be accomplished via delivery of a relatively low energy shock or through delivery of an induction stimulation pulse to the cardiac tissue timed concurrently with the vulnerable period of the cardiac cycle.

Abstract: Various system embodiments comprise a stimulator adapted to deliver a stimulation signal for a heart failure therapy, a number of sensors adapted to provide at least a first measurement of a heart failure status and a second measurement of the heart failure status, and a controller. The controller is connected to the stimulator and to the number of sensors. The controller is adapted to use the first and second measurements to create a heart failure status index, and control the stimulator to modulate the signal using the index. Other aspects and embodiments are provided herein.

Abstract: A method for managing bradycardia through vagus nerve stimulation is provided. An implantable neurostimulator configured to deliver electrical therapeutic stimulation in both afferent and efferent directions of a patient's cervical vagus nerve is provided. An operating mode is stored, which includes parametrically defining a maintenance dose of the electrical therapeutic stimulation tuned to restore cardiac autonomic balance through continuously-cycling, intermittent and periodic electrical pulses. The maintenance dose is delivered via a pulse generator through a pair of helical electrodes via an electrically coupled nerve stimulation therapy lead independent of cardiac cycle. The patient's physiology is monitored, and upon sensing a condition indicative of bradycardia, the delivery of the maintenance dose is suspended.

Abstract: The present invention comprises apparatuses and methods of detecting impacts to the head. Accelerometers attached to a user's head and neck or body is used to measure the differential acceleration of the head with respect to the neck or body. A differential acceleration exceeding a certain threshold may be indicative of the user suffering a traumatic brain injury.

Abstract: A heart monitoring method is disclosed including an electroacoustic transducer such as an earphone coupled to a controller. The method proceeds with positioning a transducer in a person's ear in acoustic communication with the tympanum. Signals from the transducer are processed to determine the presence of pulsatile blood flow. The heart monitor may be incorporated into a portable media playback device alternating between playback and monitoring mode or performing both simultaneously using one earphone for each function. The heart monitor may be incorporated into a defibrillator to sense the presence of blood flow for use in a shock delivery decision.

Abstract: In some examples, an electromechanical disassociation state (EMD) of a heart of a patient can be treated by delivering electrical stimulation to a tissue site to at least one of modulate afferent nerve activity or inhibit efferent nerve activity upon determining that the heart is in an electromechanical dissociation state, where the tissue site comprises at least one of a nonmyocardial tissue site or a nonvascular cardiac tissue site. The delivery of electrical stimulation may effectively treat the EMD state of the heart, e.g., by enabling effective mechanical contraction of the heart. In another example, an electromechanical disassociation state of a heart of a patient can be treated by determining autonomic nervous system activity associated with a detected EMD state of the heart of a patient, and delivering electrical stimulation therapy to the patient based on the determined autonomic nervous system activity of the patient associated with the EMD state.

Abstract: A defibrillating system includes a processor coupled to a memory. The processor and the memory are configured to identify a treatment event associated with treatment of a victim with the defibrillating system, and transmit a representation of a portion of an ECG signal associated with the identified treatment event. In some cases, the processor and the memory are configured to identify the portion of the ECG signal associated with the identified treatment event. In some cases, the portion of the ECG signal is of a predetermined length of time having a start time and an end time based on a time associated with the identified treatment event.

Abstract: Apparatus, systems and methods are provided for prevention and/or remediation of cardiac arrhythmias, e.g. optimizing anti-tachycardia pacing (ATP) algorithms. More particularly, implantable devices are provided that measure and treat cardiac arrhythmias. By monitoring the ATP attempt from additional electrodes, far-field morphology analyses, and/or measuring the return interval from a failed ATP attempt; the devices may estimate when entrainment has occurred, the amount of delay within the reentrant tachycardia, and/or tachycardia termination/acceleration. These variables and occurrences can be used to optimize the first and/or subsequent ATP attempts. Furthermore, other exemplary embodiments describe methods to integrate electrical restitution properties into the design of ATP pacing algorithms to facilitate tachycardia termination.

Abstract: An implantable medical device implements a special mode of operation, such as a mode of electrical stimulation therapy, during conditions where there may be an increased likelihood that a device reset will occur. The implantable medical device recovers from the device reset by copying values that specify the special mode and that are stored in a non-volatile memory to an operating memory. The special mode is implemented after the device reset has occurred by using the values copied to the operating memory. One version of the special mode is an MRI mode that allows the implantable medical device to safely operate during an MRI scan. The fields of the MRI scan may trigger a device reset, but the MRI mode values are copied from the non-volatile memory to the operating memory, and the MRI mode is implemented after the reset by using the values copied to the operating memory.

Abstract: A system and method of monitoring and reporting premature ventricular contractions (PVCs) detected in a patient is described. The method includes monitoring an electro-cardiogram (ECG) signal of the patient with an adherent device that includes a plurality of electrodes. Premature ventricular contraction (PVC) beats are detected based on the monitored ECG signal, and ECG episodes associated with detected PVC beats are stored for subsequent analysis. A morphology signal is calculated by quantifying the stored ECG episodes associated with detected PVC beats, wherein the morphology signal numerically represents the shape of the detected PVC beat. The PVC beats are then numerically clustered based on the calculated morphology signals to group PVC beats having a similar morphology or shape, and a report is generated based on the clustering of the PVC beats.

Abstract: Methods and/or devices are disclosed herein for monitoring cardiac impedance signal and delivering therapy to a patient's heart based upon the monitored cardiac impedance.

Abstract: A method and medical device for detecting a cardiac event that includes sensing a cardiac signal, identifying R-waves in the cardiac signal attendant ventricular depolarizations, determining RR-intervals between successive R-waves in response to the sensed cardiac signal, detecting an atrial tachyarrhythmia based on an analysis of the RR-intervals, iteratively sensing groups of a predetermined number of P-waves attendant atrial depolarizations in response to detecting the atrial tachyarrhythmia, and confirming the atrial tachyarrhythmia based on an analysis of the iteratively sensed groups of P-waves.

Abstract: Various system embodiments comprise a stimulator adapted to deliver a stimulation signal for a heart failure therapy, a number of sensors adapted to provide at least a first measurement of a heart failure status and a second measurement of the heart failure status, and a controller. The controller is connected to the stimulator and to the number of sensors. The controller is adapted to use the first and second measurements to create a heart failure status index, and control the stimulator to modulate the signal using the index. Other aspects and embodiments are provided herein.

Abstract: An implantable neurostimulator-implemented method for enhancing post-exercise recovery through vagus nerve stimulation is provided. An implantable neurostimulator, including a pulse generator configured to deliver electrical therapeutic stimulation in a manner that results in creation and propagation (in both afferent and efferent directions) of action potentials within neuronal fibers including a patient's cervical vagus nerve. An operating mode is stored in the pulse generator. An enhanced dose of the electrical therapeutic stimulation is parametrically defined and tuned to prevent or disrupt tachyarrhythmia through continuously-cycling, intermittent and periodic electrical pulses. The patient's physiological state is monitored during physical exercise via at least one sensor included in the implantable neurostimulator, and upon sensing a condition indicative of cessation of the physical exercise, the enhanced dose is delivered for a period of time the enhanced dose to the vagus nerve.

Abstract: A system for minimizing adverse effects to an implanted medical device (IMD) can include an automated external defibrillator and an IMD safety control. The automated external defibrillator can have a shock function having the potential to adversely affect a treatment provided by and/or the operation of the implanted medical device. The implanted medical device can be embedded within a living body, referred to as an implantee. The implanted medical device can include wireless communication capabilities. The IMD safety control can be coupled to the automated external defibrillator and can be configured to disable performance of the shock function upon the implantee when the shock function is activated and enable performance of the shock function upon resolution by an operator of the automated external defibrillator. The IMD safety control can be capable of wireless communication with the implanted medical device.

Abstract: Generally, the disclosure is directed one or more methods or systems of cardiac pacing employing a plurality of left ventricular electrodes. Pacing using a first one of the left ventricular electrodes and measuring activation times at other ones of the left and right ventricular electrodes. Pacing using a second one of the ventricular electrodes and measuring activation times at other ones of the left ventricular electrodes. Employing weighted sums of the measured activation times to measure a fusion index and select one of the left ventricular electrodes for delivery of subsequent pacing pulses based on comparing fusion indices during pacing from different LV electrodes. One or more embodiments use the same fusion index to select an optimal A-V delay by comparing fusion indices during pacing with different A-V delays at resting atrial rates as well as rates above the resting rate.

Abstract: Methods for optimizing an atrioventricular (AV) pacing delay interval based upon ECG-based optimization such that an AV pacing delay interval value can be dynamically adjusted in an ambulatory subject. Ends of P-waves are determined. An operating atrioventricular interval is modified to maintain intervals between the determined ends of P-waves and beginnings of corresponding following QRS complexes above a predetermined certain value. The value may be between 30 and 60 milliseconds.

Abstract: A rules engine acquires sensor data from sensors applied to the heart and determines whether an electrical waveform should be applied to the heart and, if so, the type of electrical waveform. A multi-phase cardiac stimulus generator generates waveforms in response to the rules engine from waveform data stored in a memory. The electrical waveform is applied to one or more electrodes implanted in or on the heart.

Abstract: According to an embodiment of a method for providing neural stimulation, activity is sensed, and neural stimulation is automatically controlled based on the sensed activity. An embodiment determines periods of rest and periods of exercise using the sensed activity, and applies neural stimulation during rest and withdrawing neural stimulation during exercise. Other embodiments are provided herein.

Abstract: In general, the disclosure describes techniques for providing conditional electrical stimulation to a patient for pelvic health. An implantable medical device (IMD) may adjust the delivery cycle of the electrical stimulation applied to a patient in response to receiving a delivery cycle parameter associated with one or more of the following: a time in a time schedule, a control device output from a control device, and physiological information from a physiological information sensing device. As an example, the IMD may monitor a status of one or more inputs of the IMD and adjust the delivery cycle of the electrical stimulation applied to the patient based on the status of the input(s).

Abstract: A medical device performs a method for computing an estimate of a physiological variable. The method includes sensing a physiological signal and measuring an event of the physiological signal. The device initializes a value of a long-term metric of the event measurement, wherein the long-term metric corresponds to a time interval correlated to a response time of the physiological variable to changes in the event. The estimate of the long-term metric is updated in a memory of the medical device using a previous long-term metric and a current measurement of the event. The device detects a need for computing the physiological variable and computes an estimate of the physiological variable using the updated long-term metric.

Abstract: An apparatus comprises an implantable cardiac signal sensing circuit configured to provide a sensed depolarization signal from a ventricle and a processor. The processor includes a signal analyzer module and a tachyarrhythmia discrimination module. The signal analyzer module is configured to determine a measure of stability of ventricular (V-V) depolarization intervals using the depolarization signal, and determine a rate of change of the measure of stability. The tachyarrhythmia discrimination module is configured to detect an episode of tachyarrhythmia using the depolarization signal, determine whether the detected tachyarrhythmia is indicative of atrial tachyarrhythmia using the determined rate of change, and provide the determination to a user or process.