Abstract: Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a catheter shaft with a plurality of electrodes coupled thereto and a processor coupled to the catheter shaft. The processor may be capable of collecting a set of signals from the plurality of electrodes, characterizing the set of signals, generating a visual representation of the set of signals and refining the visual representation.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a catheter shaft with a plurality of electrodes coupled thereto and a processor coupled to the catheter shaft. The processor may be capable of collecting a set of signals from the plurality of electrodes, generating a set of data from at least one of the set of signals, wherein the data set includes at least one known data point and one or more unknown data points, determining a non-linear distance between the at least one known data point and the one or more unknown data points, and assigning a value to at least one of the unknown data points.

Abstract: Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a catheter shaft with a plurality of electrodes coupled thereto and a processor coupled to the catheter shaft. The processor may be capable of collecting a set of signals from the plurality of electrodes and generating a data set from at least one of the set of signals. The data set may include at least one known data point and one or more unknown data points. The processor may also be capable of interpolating at least one of the unknown data points by conditioning the data set and assigning a value to at least one of the unknown data points.

Abstract: Cardiac anodal electrostimulation detection systems and methods are described, such as for distinguishing between cathodal-only capture and at least partially anodal capture (e.g., combined anodal and cathodal capture, or between two anodes of which only one captures nearby cardiac tissue, etc.).

Abstract: Medical devices and methods for using medical devices are disclosed. An example mapping medical device may include a catheter shaft with a plurality of electrodes. The plurality of electrodes may include a first pair of electrodes, a second pair of electrodes, a third pair of electrodes and a fourth pair of electrodes. The mapping medical device may further include a processor, wherein the processor may be configured to determine a first latency between the first pair of electrodes, determine a second latency between the second pair of electrodes, determine a third latency between the third pair of electrodes, determine a fourth latency between the fourth pair of electrodes, and determine a target signal by interpolating the first latency, the second latency, the third latency and the fourth latency.

Abstract: Medical devices and methods for using medical devices are disclosed. An example mapping medical device may include a catheter shaft with a plurality of electrodes. The catheter shaft may be coupled to a processor. The processor may be capable of collecting a first set of signals from a first location, collecting a second set of signals from a second location, characterizing the first set of signals over a first time period, characterizing the second set of signals over a second time period, comparing the first set of signals to the second set of signals and matching a first signal from the first set of signals with a second signal from the second set of signals.

Abstract: An improved technique is described for dealing with the detection of fusion beats when capture verification is performed by a cardiac pacing device such as during a capture threshold determination procedure. Schemes for classifying heart beats may misclassify beats as fusion beats due to feature/morphology changes in the test electrogram waveform that may occur even when capture is achieved.

Abstract: An apparatus comprises a control circuit that initiates a normal pacing mode for delivery of electrostimulation energy to the heart chamber. In response to an indication to initiate a threshold test, the control circuit determines an electrode configuration used to deliver the electrostimulation energy in the normal pacing mode, selects a first threshold test mode when a sensing electrode independent from the set of pacing electrodes is unavailable for the heart chamber, wherein a cardiac activity signal is sensed using a set of sensing electrodes that includes an electrode common to the set of pacing electrodes, and selects a second threshold test mode when a sensing electrode independent from the set of pacing electrodes is available for the heart chamber, wherein the cardiac activity signal is sensed using a set of sensing electrodes that excludes an electrode common to the set of pacing electrodes.

Abstract: Methods and device for determining a pacing vector for delivering an electrostimulation therapy are described. An implantable medical device may be configured to determine an anode capture threshold and a cathode capture threshold for a first anode and cathode pair of electrodes, switch a polarity of the first anode and cathode pair of electrodes, and determine an anode capture threshold and a cathode capture threshold for the first anode and cathode pair of electrodes having the switched polarity. The implantable medical device may be further configured to compare a cathodal capture threshold for the anode and cathode pair having the switched polarity to the anodal capture threshold of the first anode and cathode pair of electrodes and select either an anode or a cathode for delivering an electrostimulation therapy based at least in part on the comparison. Other methods and systems are also contemplated and described.

Abstract: A system and method for mapping an anatomical structure includes sensing activation signals of physiological activity with a plurality of mapping electrodes disposed in or near the anatomical structure. Patterns among the sensed activation signals are identified based on a similarity measure generated between each unique pair of identified patterns which are classified into groups based on a correlation between the corresponding pairs of similarity measures. A characteristic representation is determined for each group of similarity measures and displayed as a summary plot of the characteristic representations.

Abstract: A patient QRS duration can be received or determined, such as using one or more patient physiological sensors. A portion of the QRS duration can be determined, such as a right or left ventricular activation time. In an example, the right ventricular activation time can be determined by identifying an onset of a QRS complex and an R-wave peak in the QRS complex. In an example, when the QRS duration exceeds a threshold duration, and the RV activation time does not exceed a second threshold duration, an indication of a cardiac conduction dysfunction can be provided, such as for discriminating between left bundle branch block and right bundle branch block.

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, a pacing therapy circuit, and a controller circuit. The controller circuit includes a safety margin calculation circuit. The controller circuit initiates delivery of pacing stimulation energy to the heart using a first energy level, changes the energy level by at least one of: a) increasing the energy from the first energy level until detecting that the pacing stimulation energy induces stable capture, or b) reducing the energy from the first energy level until detecting that the stimulation energy fails to induce capture, and continues changing the stimulation energy level until confirming stable capture or the failure of capture. The safety margin calculation circuit calculates a safety margin of pacing stimulation energy using at least one of a determined stability of a parameter associated with evoked response and a determined range of energy levels corresponding to stable capture or intermittent failure of capture.

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, each of the plurality of mapping electrodes having an electrode location. A vector field map which represents a direction of propagation of the activation signals at each electrode location is generated to identify a signature pattern and a location in the vector field map according to at least one vector field template. A target location of the identified signature pattern is identified according to a corresponding electrode location.

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: 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: A system comprises a cardiac signal sensing circuit and a processor circuit. The cardiac signal sensing circuit is configured to sense a cardiac signal segment using a set of electrodes connectable to the cardiac signal sensing circuit. The processor circuit is communicatively coupled to the cardiac signal sensing circuit and includes a peak detector circuit. The peak detector circuit is configured to identify, in the cardiac signal segment, a fiducial indicative of ventricular activation that is local to at least one electrode of the first set of electrodes. The fiducial includes a first large positive or negative peak greater than a specified percentage of a maximum peak of the first cardiac signal segment. The processor circuit is configured to provide an indication of local ventricular activation to at least one of a user or process.

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 system and method for mapping an anatomical structure includes sensing activation signals of intrinsic physiological activity with a plurality of electrodes disposed in or near the anatomical structure. A most recent intrinsic event at a selected time is determined based on the sensed activation signals and a persistent display of relevant characteristics is generated based on the sensed activation signals of the most recent intrinsic event. The persistent display is updated upon detection of a subsequent intrinsic event.

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.