According to some aspects, a cardiac pacemaker for implantation within a subject is provided, the pacemaker including a housing, at least one sensor configured to detect an activity level of the subject, and at least one processor coupled to the sensor configured to detect inactivity of the subject based on output from the at least one sensor, produce a first signal configured to increase the heart rate of the subject to a first heart rate during a first time period, wherein the first heart rate is above a resting heart rate and below 100 beats per minute, and in response to determining that the first time period has elapsed, producing a second signal configured to increase the heart rate of the subject to a second heart rate during a second time period, wherein the second heart rate is between 100 and 140 beats per minute.

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.

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.

Devices and methods can be used for artificial cardiac pacing and/or resynchronization. For example, this document provides improved electrodes for stimulating and sensing electrical activity of the heart, and provides pacing and resynchronization systems incorporating such electrodes. While the devices and methods provided herein are described primarily in the context of pacing, it should be understood that resynchronization can additionally or alternatively be performed in an analogous manner, and that the scope of this disclosure includes such subject matter.

Aspects of the present disclosure are directed toward a medical device having a a core assembly. The core assembly includes a core circuit assembly and a core assembly housing configured to enclose the core circuit assembly. The core assembly housing includes a first portion, and a second portion configured to be coupled to the first portion along a weld seam. The second portion includes at least one weld joint feature, which includes a thinned section of the second portion.

Methods and systems for seamless adjustment of treatment are disclosed. A determination is made as to whether to intervene with a patient's treatment. Implanted device memory data is acquired over a pre-specified time period. Risk status is determined from the device memory data. Another external device memory data is acquired over a pre-specified time period. A determination is made as to whether to adjust treatment of the patient in response to the risk status, the data acquired from the implanted device memory and the external device memory data.

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.

Methods and systems for seamless adjustment of treatment are disclosed. A determination can be made as to whether to intervene with a patient's treatment based on data obtained from implantable electrodes and/or non-implantable electrodes. The data from non-implantable electrodes have a correction factor applied to adjust for less accuracy compared to data acquired from implantable electrodes.

A leadless pacemaker device for providing an intra-cardiac pacing includes processing circuitry configured to generate ventricular pacing signals for stimulating ventricular activity at a ventricular pacing rate, a first sensor configuration receiving a first sense signal, and a second sensor configuration receiving a second sense signal. The processing circuitry derives, in a first sensing state, atrial events from the first sense signal for controlling the ventricular pacing rate based on the atrial events. The processing circuitry switches, based on at least one switching criterion, from the first sensing state to a second sensing state in which the processing circuitry derives atrial events from the second sense signal. The second sense signal is received by the second sensor configuration for detection of atrial events and the second sensor configuration is a motion sensor or a sound sensor. A method for operating the pacemaker device is also provided.

A method and apparatus for treatment of hypertension and heart failure by increasing secretion of endogenous atrial hormones by pacing of the heart. Pacing is done during the ventricular refractory period resulting in premature atrial contraction that does not result in ventricular contraction. Pacing results in the atrial wall stress, peripheral vasodilation, ANP secretion. Concomitant reduction of the heart rate is monitored and controlled as needed with backup pacing.