In some examples, controlling delivery of CRT includes delivering ventricular pacing according to a sequence of different values of at least one of A-V delay or V-V delay, and acquiring one or more electrograms from respective vectors. For each of the different values of the at least one of A-V delay or V-V delay, at least one of a QRS amplitude or a QRS area may be determined based on the one or more electrograms, and a target change in QRS amplitude or QRS area between adjacent ones of the values of the at least one of A-V delay or V-V delay of the sequence may be identified. In response to the identification of the target change, the implantable medical device may deliver the ventricular pacing at a value of the at least one of A-V delay or V-V delay determined based on the identification to provide CRT.

Systems and methods are provided for using stored physiologic information about a subject to detect a previous treatment event. Physiologic information can be sensed from a subject using one or more sensors. Using a detection circuit, a change in the sensed physiologic information, such as a change from reference physiologic information, can be used to identify a candidate previous treatment event. An alert or other information about the candidate treatment event can be provided to a patient or clinician. In an example, a candidate treatment event can include a heart failure or diuresis treatment that is identified using information about a change in one or more of a subject's circadian pattern, a subject's thoracic impedance, or a subject's respiration status.

A system comprising: one or more sensors for detecting parameters of a respiratory cycle in a patient; and an implantable cardiac device comprising: at least one lead comprising one or more electrodes for applying cardiac contractility modulation stimulation to the heart; and circuitry for controlling and activating the leads, the circuitry programmed to set parameters of the cardiac contractility modulation stimulation according to the parameters of the respiratory cycle detected by the one or more sensors.

An implanted device for an organ of a patient including a housing. The device includes a detector having electrodes that have a varying distance over time between them which produces a detector signal based on electrical signals derived from the organ. The device includes a signal processor disposed in the housing in communication with the detector which determines admittance from the detector signal based on the varying distance over time between the electrodes. The device includes a drive circuit disposed in the housing to cause the electrodes to generate emitted electrical signals. A method for monitoring a patient's organ.

The present invention relates to a system of multiple implantable medical devices for an impedance measurement comprising a first implantable medical device, at least a second implantable medical device distinct from the first implantable medical device and; an analysis module comprising at least one amplifier and one envelope detector, one of the first implantable medical device or the second implantable medical device being a subcutaneous implantable cardioverter defibrillator or a subcutaneous loop recorder, and the other of the first implantable medical device or the second implantable medical device being an implantable endocardial device.

A ventricularly implantable medical device that includes a sensing module that is configured to detect an artifact during ventricular filling and to identify an atrial event based at least on part on the detected artifact. Control circuitry of the implantable medical device is configured to deliver a ventricular pacing therapy to a patient's heart, wherein the ventricular pacing therapy is time dependent, at least in part, on the identified atrial event.

A system to measure intracardiac impedance includes implantable electrodes and a medical device. The electrodes sense electrical signals of a heart of a subject. The medical device includes a cardiac signal sensing circuit coupled to the implantable electrodes, an impedance measurement circuit coupled to the same or different implantable electrodes, and a controller circuit coupled to the cardiac signal sensing circuit and the impedance measurement circuit. The cardiac signal sensing circuit provides a sensed cardiac signal. The impedance measurement circuit senses intracardiac impedance between the electrodes to obtain an intracardiac impedance signal. The controller circuit determines cardiac cycles of the subject using the sensed cardiac signal, and detects tachyarrhythmia using cardiac-cycle to cardiac-cycle changes in a plurality of intracardiac impedance parameters obtained from the intracardiac impedance signal.

Systems and methods for controlling blood pressure via electrical stimulation of the heart are disclosed. Embodiments may include at least two different stimulation patterns, each configured to reduce blood pressure to a different degree, and may alternate between stimulation patterns based on the need of a patient, for example, alternating between day and night or between periods of strenuous and light activity. Some embodiments may take advantage of a slow baroreflex response that occurs after treatment is stopped, suspending treatment for extended periods, and then resuming treatment before blood pressure levels reach pretreatment values. Embodiments may control blood pressure by controlling atrial pressure and atrial stretch.

Systems, methods and devices to facilitate insertion of a lead for cardiac therapy into an intercostal space associated with the cardiac notch of a patient are described including devices, methods and medical procedure templates to facilitate insertion proximate to a lateral margin of the patient's sternum.

A computing device includes a memory configured to store instructions. The computing device also includes a processor to execute the instructions to perform operations that include providing an alternating electrical signal to a patient through at least a pair of electrodes, and determining transthoracic impedance of the patient from a measurement associated with the applied alternating electrical signal. Operations also include identifying, from the transthoracic impedance, a sequence of resistance values for controlling the discharge of a charge storage device located external to the patient, and controlling the discharge of the charge storage device using the identified sequence of resistance values.