In an example, an electrocardiogram (ECG) device includes a housing, an ECG sensor, and first and second electrodes. The ECG sensor is disposed in the housing. The first electrode is accessible from outside the housing and is electrically coupled to the ECG sensor. The second electrode is accessible from outside the housing and is electrically coupled to the ECG sensor. The housing and the first and second electrodes define an ECG device electromechanical interface that is complementary to a common patch electromechanical interface that is included in at least two different types of attachment patches.

Systems and methods for ambulatory detection of Q wave-to-T wave (QT) interval prolongation are discussed. A medical-device system comprises a controller circuit and a user interface device. The controller circuit includes a long QT syndrome (LQTS) detector that measures a QT interval from a subcutaneous cardiac signal sensed from a patient using implantable electrodes, and detects an indication of QT prolongation using the measured QT time interval and a programmable threshold received as a user input from the user interface. The control circuit can adjust device operation based on the detected indication of QT prolongation. An output unit can generate a programmable alert of the QT prolongation corresponding to the user input of the programmable threshold.

Apparatus and methods remove a voltage offset from an electrical signal, specifically a biomedical signal. A signal is received at a first operational amplifier and is amplified by a gain. An amplitude of the signal is monitored, by a first pair of diode stages coupled to an output of the first operational amplifier, for the voltage offset. The amplitude of the signal is then attenuated by the first pair of diode stages and a plurality of timing banks. The attenuating includes limiting charging, by the first pair of diode stages, of the plurality of timing banks and setting a time constant based on the charging. The attenuating removes the voltage offset persisting at a threshold for a duration of at least the time constant. Saturation of the signal is limited to a saturation recovery time while the saturated signal is gradually pulled into monitoring range over the saturation recovery time.

An electrocardiogram data classification method includes: obtaining a plurality of pieces of heartbeat data according to electrocardiogram data; convolving and pooling the plurality of pieces of heartbeat data to obtain a first feature vector; obtaining a second feature vector, the second feature vector representing frequency domain feature data of the plurality of pieces of heartbeat data and time domain feature data of the plurality of pieces of heartbeat data; fusing the first feature vector and the second feature vector to generate a fusion feature vector; and obtaining classification information of the electrocardiogram data according to the fused feature vector.

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.

Techniques are disclosed for using a cardiac signal sensed via a plurality of electrodes disposed on one or more leads implanted within an epidural space of a patient to control spinal cord stimulation (SCS) therapy. In one example, an implantable medical device (IMD) senses an electrical signal via a plurality of electrodes disposed on one or more leads implanted within an epidural space of a patient. Processing circuitry determines, from the electrical signal, one or more cardiac features indicative of activity of a heart of the patient. The processing circuitry controls, based on the one or more cardiac features, delivery of SCS therapy to the patient.

Techniques are disclosed for using a cardiac signal sensed via a plurality of electrodes disposed on one or more leads implanted within an epidural space of a patient to control spinal cord stimulation (SCS) therapy. In one example, an implantable medical device (IMD) senses an electrical signal via a plurality of electrodes disposed on one or more leads implanted within an epidural space of a patient. Processing circuitry determines, from the electrical signal, one or more cardiac features indicative of activity of a heart of the patient. The processing circuitry controls, based on the one or more cardiac features, delivery of SCS therapy to the patient.

A medical device is configured to detect an atrial tachyarrhythmia episode. The device senses a cardiac signal, identifies R-waves in the cardiac signal attendant ventricular depolarizations and determines classification factors from the R-waves identified over a predetermined time period. The device classifies the predetermined time period as one of unclassified, atrial tachyarrhythmia and non-atrial tachyarrhythmia by comparing the determined classification factors to classification criteria. A classification criterion is adjusted from a first classification criterion to a second classification criterion after at least one time period being classified as atrial tachyarrhythmia. An atrial tachyarrhythmia episode is detected by the device in response to at least one subsequent time period being classified as atrial tachyarrhythmia based on the adjusted classification criterion.

A patient monitoring system for use in either a patch mode or a holster mode for monitoring physiological data of a patient includes a multi-mode sensor configured to continuously and/or intermittently acquire the physiological data from the patient in the least two modes and to transmit the acquired physiological data to a remote location and/or record the acquired physiological data in an internal memory, the physiological data including one or more of patient electrocardiogram (ECG) data, patient posture, patient movement, radio-frequency (RF) based physiological data, body temperature, and/or patient respiration; an attachment mechanism disposed on the multi-mode sensor, the attachment mechanism configured to removably connect the multi-mode sensor to either a holster and associated monitoring cables worn by the patient or a patch worn by the patient; at least one electrical contact disposed on the multi-mode sensor, the at least one electrical contact configured to engage a counterpart electrical contact of the holster and/or a counterpart electrical contact of the patch; and configuration circuitry disposed in the multi-mode sensor. The configuration circuitry is configured to determine when the multi-mode sensor is removably connected to the holster and cause the multi-mode sensor to acquire the physiological data in the holster mode when connected to the holster, and to determine when the multi-mode sensor is removably connected to the patch and cause the multi-mode sensor to acquire the physiological data in the patch mode when connected to the patch.

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.