A ventricular pacemaker is configured to determine a ventricular rate interval by determining at least one ventricular event interval between two consecutive ventricular events and determine a rate smoothing ventricular pacing interval based on the ventricular rate interval. The pacemaker is further configured to detect an atrial event from a sensor signal and deliver a ventricular pacing pulse in response to detecting the atrial event from the sensor signal. The pacemaker may start the rate smoothing ventricular pacing interval to schedule a next pacing pulse to be delivered upon expiration of the rate smoothing ventricular pacing interval.

A method of right atrial pacing of a heart of a patient includes the steps of: stimulating right atrial tissue of the heart using a right atrial lead of a dual chamber cardiac pacemaker to pace the heart with a stimulus architecture protocol; and stimulating local sympathetic and/or parasympathetic tissues with the stimulus architecture protocol proximate to the paced right atrial tissue causing nervous system activity that inhibits the autonomous nervous system to reduce blood pressure. A closed loop system operating according to this method and a cardiac pacing lead for implementing this method also are included within the scope of the illustrated embodiments.

Systems and methods are described herein for configuration of cardiac therapy. The systems and methods may select, or determine, a plurality of different configuration parameters based electrical activity monitored or measured using a plurality of external electrodes. For example, the systems and methods may select, or determine, a left ventricular pacing vector, adaptive or non-adaptive pacing therapy, an interventricular pacing delay, and a atrioventricular pacing delay.

A method of communication in a system comprising plurality of implantable medical devices, where a first device comprises a means for detection of a signal representative of atrial activity, a transmitter, and a controller, and a second device independent of the first device, the second device comprising a receiver and a controller. The method comprises synchronizing the first device with the second device, determining the duration of a cardiac cycle, determining a synchronization interval, the duration of the synchronization interval determined as a function of the duration of the cardiac cycle, the synchronization interval being shorter than the duration of the cardiac cycle, and the start of the synchronization interval is determined as a function of the synchronization signal, and activating the receiver of the second device during the synchronization interval, wherein the receiver of the second device is deactivated outside of the synchronization interval.

Systems, methods and implantable devices configured to provide cardiac resynchronization therapy and/or bradycardia pacing therapy. A first device located in the heart of the patient is configured to receive a communication from a second device and deliver a pacing therapy in response to or in accordance with the received communication. A second device located elsewhere is configured to determine an atrial event has occurred and communicate to the first device to trigger the pacing therapy. The second device may be configured for sensing the atrial event by the use of vector selection and atrial event windowing, among other enhancements. Exception cases are discussed and handled as well.

An implantable system, and methodology, for improving a heart's hemodynamic performance featuring (a) bimodal electrodes placeable on the diaphragm, out of contact with the heart, possessing one mode for sensing cardiac electrical activity, and another for applying cardiac-cycle-synchronized, asymptomatic electrical stimulation to the diaphragm to trigger biphasic, diaphragmatic motion, (b) an accelerometer adjacent the electrodes for sensing both heart sounds, and stimulation-induced diaphragmatic motion, and (c) circuit structure, connected both to the electrodes and the accelerometer, operable, in predetermined timed relationships to the presences of valid V-events noted in one of sensed electrical and sensed mechanical, cardiac activity, to deliver diaphragmatic stimulation. The circuit structure includes accelerometer-linked computer structure for enabling selective review, for later operational modifications, of stimulation-produced diaphragmatic motions, and in a modified form, may additionally include timing-adjustment substructure capable of making adjustments in the mentioned timed relationships.

Systems, devices, and methods for improving wireless power transmission are disclosed herein. A method of powering an implantable ventricular assist device with an external charging device includes receiving a signal indicative of a change in a property of a deformable coil of the resonant circuit. A performance property of the deformable coil is determined based on the signal. An adjustment to a tuning of the resonant circuit is identified based on the performance property of the deformable coil. The resonant circuit is tuned according to the adjustment to the tuning of the resonant circuit. The resonant circuit is driven to transmit power to a secondary coil electrically coupled with the implantable ventricular assist device to power the ventricular assist device.

Systems and methods for monitoring patient vasoactivity are discussed. An exemplary patient monitor system includes a sensor circuit configured to generate a heart sound (HS) metric using a HS signal sensed from a patient, and a vasoactivity monitor configured to monitor vasoactivity, such as degree of vasoconstriction or vasodilation, using the HS metric. The system can provide the monitored vasoactivity to a user to alert patient hemodynamic responses to vasoactive drugs, or initiate or adjust a vasoactive therapy according to the vasoactivity. The system may use the monitored vasoactivity to detect a medical condition such as worsening heart failure, pulmonary edema, or syncope.

A medical tool includes a rotation mechanism that further includes a warning feature. The warning feature provides an indication when the rotation mechanism has achieved a number of rotations.

This document discusses, among other things, systems and methods to determine an alert state for a patient using received physiologic information, determine an event rate for the alert state, and adjust determination of a composite risk for the patient using the determined event rate.