An electrode apparatus includes a portable amplifier and a plurality of external electrodes to be disposed proximate a patient's skin. A portable computing apparatus is operably coupled to the electrode apparatus. The portable computing apparatus is configured to monitor electrical activity from tissue of a patient using the plurality of external electrodes to generate a plurality of electrical signals over time. The portable computing apparatus is configured to perform at least one of optimizing at least one parameter of the of the implantable pacing device based on the plurality of electrical signals and determining cardiac synchrony based on the plurality of electrical signals.

In some examples, a leadless pacing device (LPD) is configured to switch from a sensing without pacing mode to ventricular pacing mode in response to determining that no intrinsic ventricular activity was detected within a ventricular event detection window for at least one cardiac cycle, which may be referred to as loss of conduction. The ventricular pacing mode may be selected based on whether atrial oversensing is detected in combination with the loss of conduction. In some examples, an atrio-ventricular synchronous pacing mode is selected in response to detecting loss of conduction and in response to determining that atrial oversensing is not detected. In addition, in some examples, an asynchronous ventricular pacing mode is selected in response to detecting both atrial oversensing and loss of conduction.

An implantable medical device includes an activity sensor, a pulse generator, and a control module. The control module is configured to determine activity metrics from the activity signal and determine an activity metric value at a predetermined percentile of the activity metrics. The control module sets a lower pacing rate set point based on the activity metric value at the predetermined percentile.

Methods and devices for reducing ventricle filling volume are disclosed. In some embodiments, an electrical stimulator may be used to stimulate a patient's heart to reduce ventricle filling volume or even blood pressure. When the heart is stimulated in a consistent way to reduce blood pressure, the cardiovascular system may over time adapt to the stimulation and revert back to the higher blood pressure. In some embodiments, the stimulation pattern may be configured to be inconsistent such that the adaptation response of the heart is reduced or even prevented. In some embodiments, an electrical stimulator may be used to stimulate a patient's heart to cause at least a portion of an atrial contraction to occur while the atrioventricular valve is closed. Such an atrial contraction may deposit less blood into the corresponding ventricle than when the atrioventricular valve is opened throughout an atrial contraction.

One embodiment provides a system for determination and utilization of cardiac electrical asynchrony data. The system includes an analysis circuitry including a processor and a memory, the analysis circuitry configured to: obtain a plurality of sets of cardiac signals collected in at least two locations of a heart of a patient, the signals comprising at least one of surface electrocardiography signals and pseudo-surface ECG signals; detect one or more QRS complexes for each of the sets based on the cardiac signals for that set; obtain one or more cross-correlation signals, each of the cross-correlation signals being between at least two of the signal sets and being obtained using the detected QRS complexes from the signal sets; and calculate one or more asynchrony indices using one or more of the cross-correlation signals, each of the asynchrony indices being indicative of a level of asynchrony between the at least two locations.

Pacing parameters may be adjusted to increase the cardiac output of a patient's heart while a patient is awake and/or active and the demand placed on the heart may be greatest, and to decrease or hemodynamic efficiency while a patient is at rest so that the heart itself has time to rest before the next period of higher demand for efficiency begins. This may aid in lessening the strain placed on the heart by making the heart work hard when needed such as when the patient is active, and by permitting the heart to “rest” when the patient is relatively inactive.

An intracardiac ventricular pacemaker is configured to detect an atrial mechanical event from a motion sensor signal received by an atrial event detector circuit of the pacemaker. The motion sensor signal is responsive the motion of blood flowing in the ventricle. A pacing pulse is scheduled at an expiration of a pacing interval set by a pace timing circuit in response to detecting the atrial mechanical event. An atrial-synchronized ventricular pacing pulse is delivered upon expiration of the pacing interval.

A method for identifying reversible cardiac dyssynchrony (RCD) of a patient and treating the RCD measures an event relating to a rapid increase in the rate of pressure increase within the left ventricle. The method calculates a first time delay between the event and a first reference time. If the first time delay is longer than a set fraction of electrical activation of the heart, then the presence of cardiac dyssynchrony in the patient is identified. Pacing is applied to the heart, and a second time delay between the event following pacing and a second reference time following pacing is calculated. If the second time delay is shorter than the first time delay, the method identifies a shortening of a delay to onset of myocardial synergy, OoS, thereby identifying the presence of RCD in the patient. Treatment of the RCD is performed.

Systems and methods for optimizing the stimulation of a heart of a patient are disclosed herein. The method comprises delivering pacing therapy to the patient according to a pacing therapy setting schedule, using specific pacing intervals via specific electrode configurations. Further, sinus rate values are recorded over at least one cardiac cycle at each pacing therapy setting and it is determined whether a sinus rate value satisfies predetermined measurement conditions, wherein sinus rate values are used for trending the sinus rate over time if the measurement conditions are satisfied. The accepted sinus rate values, i.e. values that satisfy the measurement conditions, are trended over time, wherein each trended sinus rate value is created based on recordings from at least one cardiac cycle. A preferred pacing therapy setting is determined to be the pacing therapy setting that provides a lowest sinus rate.

Systems and methods for treating atrial tachyarrhythmias such as atrial fibrillation (AF) are disclosed. By monitoring a patient's hemodynamic sensor response to a candidate AF therapy, the present systems and methods can be used to determine an individualized AF therapy leading to a desirable hemodynamic outcome. A medical system can include one or more programmable therapy circuits and a hemodynamic sensor circuit. The system includes a therapy selection circuit that automatically programs and sequentially delivers at least a first candidate therapy and a different second candidate therapy. By comparing the values of a hemodynamic parameter in response to or during the first candidate therapy to that in response to or during the second candidate therapy, a desired AF therapy can be determined as the candidate therapy that leads to faster or more significant hemodynamic recovery.