Abstract: Systems and methods for rate-adaptive pacing are disclosed. In one illustrative embodiment, a medical device for delivering electrical stimulation to a heart may include a housing configured to be implanted on the heart or within a chamber of the heart, one or more electrodes connected to the housing, and a controller disposed within the housing. The controller may be configured to sense a first signal and determine a respiration rate based at least in part on the sensed first signal. In at least some embodiments, the controller may be further configured to adjust a rate of delivery of electrical stimulation by the medical device based at least in part on the determined respiration rate.

Abstract: A catheter system includes a mapping catheter including a plurality of mapping electrodes, each mapping electrode configured to sense signals associated with an anatomical structure. The catheter system further includes a processor operatively coupled to the plurality of mapping electrodes and configured to receive the signals sensed by the plurality of mapping electrodes, characterize the signals sensed by the plurality of mapping electrodes based on amplitudes of the sensed signals, and generate an output of a quality of contact of the plurality of mapping electrodes with the anatomical structure based on the signal characterization.

Abstract: A system for use during revascularization includes a catheter having an adjustable balloon for delivery a stent, one or more pacing electrodes for delivering one or more pacing pulses to a patient's heart, and a pacemaker configured to generate the one or more pacing pulses to be delivered to the heart via the one or more pacing electrodes. The one or more pacing pulses are delivered at a rate substantially higher than the patient's intrinsic heart rate without being synchronized to the patient's intrinsic cardiac contractions, and are delivered before, during, or after an ischemic event to prevent or reduce cardiac injury.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to a first electrode over a time period and generating a first time-frequency distribution corresponding to the first signal. The first time-frequency distribution includes a first dominant frequency value representation occurring at one or more first base frequencies. The processor is also capable of applying a filter to the first signal or derivatives thereof to determine whether the first dominant frequency value representation includes a single first dominant frequency value at a first base frequency or two or more first dominant frequency values at two or more base frequencies.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example system for mapping the electrical activity of the heart includes a catheter shaft. The catheter shaft includes a plurality of electrodes including a first electrode and a second electrode. The system also includes a processor. The processor is capable of collecting a first signal corresponding to the first electrode and a second signal corresponding to the second electrode. Collecting the first and second signals occurs over a time period. The processor is also capable of generating a first time-frequency distribution corresponding to the first signal, identifying a first dominant frequency value occurring at a first dominant frequency and a first time point, generating a second time-frequency distribution corresponding to the second signal, identifying a second dominant frequency value occurring at a second dominant frequency and a second time point and determining an attraction point.

Abstract: A system for facilitating placement of a lead in or on a patient's heart includes a first lead apparatus, a second lead apparatus, a user interface, and a processor. The processor is configured to measure a distance parameter indicative of a distance between a reference sensor element at a right heart location and a lead apparatus sensor element at each of a plurality of left heart locations in either the left ventricle or a coronary venous pathway, determine a separation distance for each of the plurality of left heart locations from the right heart location based on the distance parameter measurements, and determine that the separation distance for a location of the plurality of left heart locations from the right heart location is less than a threshold distance based on the separation distance for the location. The threshold distance representative of unsuitability for pacing.

Abstract: Various system embodiments comprise a lead having a distal end and a proximal end. The distal end includes a plurality of electrodes. The lead is configured to be fed into a dorsal epidural space of a human to a desired region of a spinal column and to be fed laterally to at least partially encircle a spinal cord in the desired region to place at least one stimulation electrode in position to stimulate a dorsal nerve root and at least another stimulation electrode in position to stimulate a ventral nerve root. The desired region may include cervical vertebrae, thoracic vertebrae, or lumbar vertebrae. Some embodiments stimulate the spinal cord in the T1-T5 region.

Abstract: Various system embodiments comprise an implantable lead, an implantable housing, a neural stimulation circuit in the housing, and a controller in the housing and connected to the neural stimulation circuit. The lead has a proximal end and a distal end. The distal end is adapted to deliver neural stimulation pulses to the ventral nerve root and the dorsal nerve root. The proximal end of the lead is adapted to connect to the housing. The neural stimulation circuit is adapted to generate neural stimulation pulses to stimulate the ventral nerve root or the dorsal nerve root using the implantable lead. The controller is adapted to control the neural stimulation circuit to deliver a neural stimulation treatment.

Abstract: An anatomical mapping system and method includes mapping electrodes configured to detect activation signals of cardiac activity. A processing system is configured to record the detected activation signals and generate a vector field for each sensed activation signal during each instance of the physiological activity. The processing system determines an onset time and alternative onset time candidates, identifies an initial vector field template based on a degree of similarity between the initial vector field and a vector field template from a bank of templates, then determines an optimized onset time for each activation signal based on a degree similarity between the onset time candidates and initial vector field template.

Abstract: Described are methods and devices for improving diastolic function with electrostimulation in heart failure patients who exhibit relatively normal systolic function. Such patients are characterized by impaired myocardial relaxation during diastole that prevents adequate filling of the ventricles during diastole to thereby reduce cardiac output. An implantable device is described for effecting strategic and periodic stimulation of the sympathetic nervous system to elicit myocardial adrenergic activation for improved myocardial relaxation.

Abstract: Methods for modulating nerve function are disclosed. An example method for modulating nerve function may include providing a transgene including a neuron-specific promoter and a gene encoding a light-sensitive protein, delivering the transgene to a body tissue including one or more target neurons, implanting a light source adjacent to the cell bodies of the one or more target neurons, and emitting light from the light source. Light may be exposed to the cell bodies of the one or more target neurons and may cause a conformational change in the light-sensitive protein.

Abstract: Various system embodiments comprise an implantable lead, an implantable housing, a neural stimulation circuit in the housing, and a controller in the housing and connected to the neural stimulation circuit. The lead has a proximal end and a distal end. The distal end is adapted to deliver neural stimulation pulses to the ventral nerve root and the dorsal nerve root. The proximal end of the lead is adapted to connect to the housing. The neural stimulation circuit is adapted to generate neural stimulation pulses to stimulate the ventral nerve root or the dorsal nerve root using the implantable lead. The controller is adapted to control the neural stimulation circuit to deliver a neural stimulation treatment.

Abstract: Various system embodiments comprise a lead having a distal end and a proximal end. The distal end includes a plurality of electrodes. The lead is configured to be fed into a dorsal epidural space of a human to a desired region of a spinal column and to be fed laterally to at least partially encircle a spinal cord in the desired region to place at least one stimulation electrode in position to stimulate a dorsal nerve root and at least another stimulation electrode in position to stimulate a ventral nerve root. The desired region may include cervical vertebrae, thoracic vertebrae, or lumbar vertebrae. Some embodiments stimulate the spinal cord in the T1-T5 region.

Abstract: A system for use during revascularization includes a catheter having an adjustable balloon for delivery a stent, one or more pacing electrodes for delivering one or more pacing pulses to a patient's heart, and a pacemaker configured to generate the one or more pacing pulses to be delivered to the heart via the one or more pacing electrodes. The one or more pacing pulses are delivered at a rate substantially higher than the patient's intrinsic heart rate without being synchronized to the patient's intrinsic cardiac contractions, and are delivered before, during, or after an ischemic event to prevent or reduce cardiac injury.

Abstract: Acoustic energy is delivered to innervated vascular that contributes to renal sympathetic nerve activity, such as innervated tissue of the renal artery and abdominal aorta. Focused acoustic energy is delivered via an intravascular device of sufficient power to ablate innervated renal or aortal tissue. Focused acoustic energy may be delivered via an intravascular or extracorporeal device to image and locate target innervated renal or aortal tissue. Intravascular, extravascular, or transvascular focused ultrasound devices provide for high precision denervation of innervated vascular to terminate renal sympathetic nerve activity.

Abstract: A method and system for mapping an anatomical structure includes sensing activation signals of intrinsic physiological activity with a plurality of mapping electrodes disposed in or near the anatomical structure. The activation signals are used to determine a dominant frequency for each electrode from which a wavefront vector for each electrode is determined based on a difference between the dominant frequency at a first electrode location and the dominant frequency at neighboring electrodes. An anatomical map is generated based on the determined wavefront vectors.

Abstract: An apparatus comprises an implantable sensor and a detection circuit. The implantable sensor provides a physiologic sensor signal and is to be positioned at a lymph node of a subject. The detection circuit detects a change in a physiologic parameter of the lymph node that exceeds a threshold change, and deems that the change in the physiologic parameter indicates a change in inflammation of an organ associated with the lymph node.

Abstract: A cardiac rhythm management system provides for cardiac pacing that is delivered to a target portion of conductive tissue in a heart, such as the His bundle. In various embodiments, the system is configured to verify capture of the target portion and provide for selective pacing of the target portion. In various embodiments, the system is configured to detect responses of the target portion and adjacent myocardial tissue to delivery of pacing pulses and use an outcome of the detection to verify selective capture of the target portion (i.e., without directly exciting the adjacent myocardial tissue.

Abstract: Systems and methods facilitate placement of a lead in or on a patient's heart. At least one reference sensor is positioned at a right heart location of a patient's heart and a cardiac lead apparatus comprising at least one lead apparatus sensor is advanced to a plurality of left heart locations. Using the reference sensor and the lead apparatus sensor, a distance parameter indicative of a distance between the reference and lead apparatus sensors is measured for each of the plurality of left heart locations. Strain or stress estimates are determined for the plurality of left heart locations derived from the distance parameter measurements. Using the strain or stress estimates, a physician perceivable output is produced indicating suitability of the left heart locations as pacing sites.

Abstract: An anatomical mapping system and method includes mapping electrodes configured to detect activation signals of cardiac activity. A processing system is configured to record the detected activation signals and generate a vector field for each sensed activation signal during each instance of the physiological activity. The processing system determines an onset time and alternative onset time candidates, identifies an initial vector field template based on a degree of similarity between the initial vector field and a vector field template from a bank of templates, then determines an optimized onset time for each activation signal based on a degree similarity between the onset time candidates and initial vector field template.