Abstract: A method of operating a cardiac therapy system to deliver cardiac resynchronization therapy (CRT) pacing that includes pacing both ventricles or pacing only the left ventricle is described. Delivery of the CRT pacing to one or both ventricles is scheduled for a cardiac cycle. If an intrinsic depolarization of a ventricle is detected during a pacing delay of the ventricle, then the scheduled CRT pacing to the ventricle is inhibited for the cycle. The intrinsic interval of the ventricle, such as the intrinsic atrioventricular interval concluded by the intrinsic depolarization, is measured. During a subsequent cardiac cycle, the pacing delay of the ventricle is decreased to be less than or equal to the measured intrinsic interval. Capture of the ventricle is verified after pacing is delivered during the subsequent cardiac cycle.

Abstract: An A-H delay can be specified, such as by computing the A-H delay using a measured cardiovascular physiologic parameter. The A-H delay can be used for specifying timing between a paced or sensed atrial contraction and a His-bundle pacing time.

Abstract: Approaches to rank potential left ventricular (LV) pacing vectors are described. Early elimination tests are performed to determine the viability of LV cathode electrodes. Some LV cathodes are eliminated from further testing based on the early elimination tests. LV cathodes identified as viable cathodes are tested further. Viable LV cathode electrodes are tested for hemodynamic efficacy. Cardiac capture and phrenic nerve activation thresholds are then measured for potential LV pacing vectors comprising a viable LV cathode electrode and an anode electrode. The potential LV pacing vectors are ranked based on one or more of the hemodynamic efficacy of the LV cathodes, the cardiac capture thresholds, and the phrenic nerve activation thresholds.

Abstract: An apparatus comprises a cardiac signal sensing circuit and a first implantable electrode pair. At least one electrode of the first implantable electrode pair is configured for placement at a location in a right branch of a His bundle of the subject. The apparatus can include a therapy circuit and a control circuit. The control circuit can include an AH delay calculation circuit configured to calculate an optimal paced AH delay interval. The pacing stimulation location is distal to a location of RV conduction block in a right branch of the His bundle. The control circuit initiates delivery of an electrical stimulation pulse to the stimulation location in the His bundle according to the calculated paced AH delay interval and in response to an intrinsic depolarization event sensed in an atrium of the subject.

Abstract: Approaches to rank potential left ventricular (LV) pacing vectors are described. Early elimination tests are performed to determine the viability of LV cathode electrodes. Some LV cathodes are eliminated from further testing based on the early elimination tests. LV cathodes identified as viable cathodes are tested further. Viable LV cathode electrodes are tested for hemodynamic efficacy. Cardiac capture and phrenic nerve activation thresholds are then measured for potential LV pacing vectors comprising a viable LV cathode electrode and an anode electrode. The potential LV pacing vectors are ranked based on one or more of the hemodynamic efficacy of the LV cathodes, the cardiac capture thresholds, and the phrenic nerve activation thresholds.

Abstract: A method and apparatus for selection of one or more ventricular chambers to stimulate for ventricular resynchronization therapy. Intrinsic intracardia electrograms that include QRS complexes, are recorded from a left and right ventricle. A timing relationship between the intrinsic intracardia electrograms recorded from the left and right ventricle is then determined. In one embodiment, the timing relationship is determined using a delay between a left ventricular and a right ventricular sensed intrinsic ventricular depolarizations and a duration interval of one or more QRS complexes. In one embodiment, the duration of QRS complexes is determined from either intracardiac electrograms or from surface ECG recordings. One or more ventricular chambers in which to provide pacing pulses are then selected based on the timing relationship between intrinsic intracardia electrograms recorded from the right and left ventricle, and the duration of one or more QRS complexes.

Abstract: A system comprises a cardiac signal sensing and a processing circuit. The cardiac signal sensing circuit senses a first cardiac signal segment that includes a QRS complex and a second cardiac signal segment that includes a fiducial indicative of local ventricular activation. The processor circuit includes a site activation timer circuit configured to determine a time duration between a fiducial of the QRS complex of the first cardiac signal segment and the fiducial of the second cardiac signal segment. The processor circuit is configured to generate, using the determined time duration, an indication of optimality of placement of one or more electrodes for delivering therapy and provide the indication to at least one of a user or process.

Abstract: An X-ray lens is provided. The lens is located behind an X-ray tube and a collimator, the collimator located behind the X-ray tube, such that X-rays emitted from the X-ray tube pass through the collimator and then pass through the X-ray lens, wherein the X-ray lens is a monolithic capillary parallel lens configured to transform a cone emanant beam penetrating the collimator into parallel X-rays.

Abstract: Methods and systems are disclosed for determining whether a patient is a responder to cardiac resynchronization therapy. The beginning and ending of the intrinsic ventricular depolarization are determined through signals measured from one or more electrodes implanted in the patient's heart. An interval between the beginning and ending of the intrinsic ventricular depolarization is computed and is compared to a threshold. The threshold may be determined empirically. The pacing parameters of a heart stimulation device, such as a pacemaker, may then be configured, for example, by setting the paced atrio-ventricular delay based on whether the patient responds positively to cardiac resynchronization therapy.

Abstract: A cardiac rhythm management system modulates the delivery of pacing and/or autonomic neurostimulation pulses based on heart rate variability (HRV). An HRV parameter being a measure of the HRV is produced to indicate a patient's cardiac condition, based on which the delivery of pacing and/or autonomic neurostimulation pulses is started, stopped, adjusted, or optimized. In one embodiment, the HRV parameter is used as a safety check to stop an electrical therapy when it is believed to be potentially harmful to continue the therapy.

Abstract: A method and apparatus for selection of one or more ventricular chambers to stimulate for ventricular resynchronization therapy. Intrinsic intracardia electrograms that include QRS complexes, are recorded from a left and right ventricle. A timing relationship between the intrinsic intracardia electrograms recorded from the left and right ventricle is then determined. In one embodiment, the timing relationship is determined using a delay between a left ventricular and a right ventricular sensed intrinsic ventricular depolarizations and a duration interval of one or more QRS complexes. In one embodiment, the duration of QRS complexes is determined from either intracardiac electrograms or from surface ECG recordings. One or more ventricular chambers in which to provide pacing pulses are then selected based on the timing relationship between intrinsic intracardia electrograms recorded from the right and left ventricle, and the duration of one or more QRS complexes.

Abstract: A cardiac rhythm management system modulates the delivery of pacing and/or autonomic neurostimulation pulses based on heart rate variability (HRV). An HRV parameter being a measure of the HRV is produced to indicate a patient's cardiac condition, based on which the delivery of pacing and/or autonomic neurostimulation pulses is started, stopped, adjusted, or optimized. In one embodiment, the HRV parameter is used to evaluate a plurality of parameter values for selecting an approximately optimal parameter value.

Abstract: A system comprising an implantable electrical cardiac signal sensing circuit, an implantable sinoatrial cardiac action potential detector circuit, and an implantable electrical stimulation circuit in electrical communication with the electrical cardiac signal sensing circuit and the sinoatrial cardiac action potential detector circuit. The electrical cardiac signal sensing circuit is configured to receive one or more intrinsic heart signals from one or more respective electrodes configured for placement in a vicinity of a sinoatrial node of a subject. The implantable electrical stimulation circuit is configured to initiate delivery of at least one inhibitory electrical stimulation pulse in a vicinity of the sinoatrial node in a timed relationship to a sensed sinoatrial cardiac action potential. Other systems and methods are disclosed.

Abstract: A space curve mesh driving pair and a polyhedral space curve mesh transmission are disclosed. Said space curve mesh driving pair consists of a driving wheel and a driven wheel. Axes of the driving wheel and the driven wheel are intersected at an angle of 0°˜180°, and power transmission is realized by continuous mesh between the driving tines and the driven tines; a number of driving tines are provided on said driving wheel, and a number of driven tines are provided on the driven wheel; the driving tines are uniformly arranged on an end face of a cylinder of the driving wheel, and the driven tines are uniformly arranged on the circumference of a cylindrical surface of the driven wheel. Said polyhedral space curve mesh transmission consists of an above-mentioned space curve mesh driving pair. Motion is input from an input end, and is passed through a number of pace curve mesh driving pairs to realize the speed change, then is output from one or more output ends.

Abstract: Methods and devices are disclosed for employing mechanical measurements to synchronize contractions of ventricular wall locations. Accelerometers that may be placed within electrode leads are positioned at ventricular wall locations, such as the left ventricle free wall, right ventricle free wall, and the anterior wall/septum wall. The accelerometers produce signals in response to the motion of the ventricular wall locations. A processor may then compare the signals to determine a difference in the synchronization of the ventricular wall location contractions. The difference in synchronization can be determined in various ways such as computing a phase difference and/or amplitude difference between the accelerometer signals. One or more stimulation pulses may be provided per cardiac cycle to resynchronize the contractions as measured by the accelerometers to thereby constantly and automatically optimize the cardiac resynchronization therapy.

Abstract: Stimulation energy can be provided to a His-bundle to activate natural cardiac contraction mechanisms. Interval information can be used to describe a cardiac response to His-bundle stimulation, and the interval information can provide cardiac stimulation diagnostic information. For example, interval information can be used to discriminate between intrinsic conduction cardiac contractions and contractions responsive to His-bundle pacing.

Abstract: Vector selection is automatically achieved via a thoracic or intracardiac impedance signal collected in a cardiac function management device or other implantable medical device that includes a test mode and a diagnostic mode. During a test mode, the device cycles through various electrode configurations for collecting thoracic impedance data. At least one figure of merit is calculated from the impedance data for each such electrode configuration. In one example, only non-arrhythmic beats are used for computing the figure of merit. A particular electrode configuration is automatically selected using the figure of merit. During a diagnostic mode, the device collects impedance data using the selected electrode configuration. In one example, the figure of merit includes a ratio of a cardiac stroke amplitude and a respiration amplitude. Other examples of the figure of merit are also described.

Abstract: A truckle for a mobile medical device is provided. The truckle includes at least one electromagnetism torque balancing motor mounted on the truckle and configured to balance out friction generated by the truckle.

Abstract: An apparatus comprises a cardiac signal sensing circuit and a first implantable electrode pair. At least one electrode of the first implantable electrode pair is configured for placement at a location in a right branch of a His bundle of the subject. The apparatus can include a therapy circuit and a control circuit. The control circuit can include an AH delay calculation circuit configured to calculate an optimal paced AH delay interval. The pacing stimulation location is distal to a location of RV conduction block in a right branch of the His bundle. The control circuit initiates delivery of an electrical stimulation pulse to the stimulation location in the His bundle according to the calculated paced AH delay interval and in response to an intrinsic depolarization event sensed in an atrium of the subject.

Abstract: A method of operating a cardiac therapy system to deliver cardiac resynchronization therapy (CRT) pacing that includes pacing both ventricles or pacing only the left ventricle is described. Delivery of the CRT pacing to one or both ventricles is scheduled for a cardiac cycle. If an intrinsic depolarization of a ventricle is detected during a pacing delay of the ventricle, then the scheduled CRT pacing to the ventricle is inhibited for the cycle. The intrinsic interval of the ventricle, such as the intrinsic atrioventricular interval concluded by the intrinsic depolarization, is measured. During a subsequent cardiac cycle, the pacing delay of the ventricle is decreased to be less than or equal to the measured intrinsic interval. Capture of the ventricle is verified after pacing is delivered during the subsequent cardiac cycle.