The exemplified methods and systems facilitate one or more dynamical analyses that can characterize and identify synchronicity between acquired cardiac signals and photoplethysmographic signals to predict/estimate presence, non-presence, localization, and/or severity of abnormal cardiovascular conditions or disease, including, for example, but not limited to, coronary artery disease, heart failure (including but not limited to indicators of disease or conduction such as abnormal left ventricular end-diastolic pressure disease), and pulmonary hypertension, among others. In some embodiments, statistical properties of the synchronicity between cardiac signals and photoplethysmographic signals are evaluated. In some embodiments, statistical properties of histogram of synchronicity between cardiac signals and photoplethysmographic signals are evaluated. In some embodiments, statistical and/or geometric properties of Poincar map of synchronicity between cardiac signals and photoplethysmographic signals are evaluated.

In an example, a system includes an ultrasound sensor configured to transmit ultrasound energy and receive ultrasound energy reflected in a region of a patient and one or more processors configured to generate a reference ultrasound image of the region of the patient based on a portion of the ultrasound energy that was received by the ultrasound sensor prior to a medical instrument or medical device causing obstruction in the received ultrasound energy, generate a live ultrasound image based on a current portion of the received ultrasound energy obtained by the ultrasound sensor, register the reference ultrasound image and the live ultrasound image, and control a display device to display the reference ultrasound image with at least a portion of the live ultrasound image.

Systems and methods for facilitating display of cardiac information based on sensed electrical signals include a processing unit configured to receive a set of electrical signals; receive an indication of a measurement location corresponding to each electrical signal of the set of electrical signals; and generate an activation histogram corresponding to the set of electrical signals. Systems and methods disclosed herein may be configured to automatically identify activation histograms exhibiting split characteristics, and to facilitate presentation, on a display device, of a cardiac map including highlighted regions corresponding to the identified activation histograms.

Methods, systems and devices for providing cardiac resynchronization therapy (CRT) to a patient using a leadless cardiac pacemaker and an extracardiac device. The extracardiac device is configured to analyze one or more QRS complexes of the patient's heart, determine whether fusion pacing is taking place, and, if not, to communicate with the leadless cardiac pacemaker to adjust intervals used in the CRT in order to generate desirable fusion of the pace and intrinsic signals. The extracardiac device may take the form of a subcutaneous implantable monitor, a subcutaneous implantable defibrillator, or other devices including wearable devices.

The present application discloses an apparatus for determining a blood pressure of a subject, the apparatus includes a sensor assembly configured to measure a pulse wave signal of the subject; and a signal processor configured to generate a metric of the pulse wave signal based on the pulse wave signal, to select a blood pressure calculation algorithm base on the metric of the pulse wave signal, and to determine the blood pressure of the subject using the blood pressure calculation algorithm.

Systems and methods are provided for delivering neurostimulation therapies to patients. A titration process is used to gradually increase the stimulation intensity to a desired therapeutic level until a target T-wave alternans change from a baseline T-wave alternans is achieved.

According to at least one aspect, a wearable cardiac device is provided. The wearable cardiac device includes a garment worn about a torso of a patient, at least one sensing electrode to monitor cardiac activity of the patient, and a controller including a plurality of separate and distinct modules distributed about and/or integrated into the garment. The plurality of separate and distinct modules includes, for example, an operations module coupled to the at least one sensing electrode and configured to detect at least one cardiac condition of the patient and/or a communications module coupled to the operations module to communicate with an external device. In some examples, the wearable cardiac device may be configured as a treatment device and include an energy storage module coupled to at least one therapy electrode and configured to store energy for at least one therapeutic shock to be applied to the patient.

A method includes receiving an anatomical map of at least a portion of a heart. Positions and respective bipolar intracardiac electrogram (EGM) signals measured at the positions are received for at least a region of the anatomical map. Primary activations and secondary activations are identified in the bipolar intracardiac EGM signals. A surface representation of the bipolar intracardiac EGM signals over the region is derived, including the identified primary activations and secondary activations. The surface representation is presented overlaid on the anatomical map.

A guidance and placement system and associated methods for assisting a clinician in the placement of a catheter or other medical device within the vasculature of a patient is disclosed. In one embodiment, a method for guiding a medical device to a desired location within a vasculature of a patient is also disclosed and comprises detecting an intravascular ECG signal of the patient and identifying a P-wave of a waveform of the intravascular ECG signal, wherein the P-wave varies according to proximity of the medical device to the desired location. The method further comprises determining whether the identified P-wave is elevated, determining a deflection value of the identified P-wave when the identified P-wave is elevated, and reporting information relating to a location of the medical device within the patient's vasculature at least partially according to the determined deflection value of the elevated P-wave.

Systems and methods for facilitating processing of cardiac information based on sensed electrical signals include a processing unit configured to receive a set of electrical signals; receive an indication of a measurement location corresponding to each electrical signal of the set of electrical signals; and generate, based on at least one of an annotation waveform corresponding to each electrical signal of the set of electrical signals and a set of annotation mapping values, an annotation histogram.