摘要:
Methods and systems involve classifying the cardiac response to pacing using a multi-channel approach. Multiple cardiac response signals are sensed via multiple sense channels. Each sense channel comprises a distinct combination of electrodes and sensing circuitry. The cardiac response to the pacing pulse is classified based on the morphology of the cardiac response signals. Classifying the cardiac response involves discriminating between capture, fusion, non-capture, and non-capture with intrinsic activity.
摘要:
Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed to detect, monitor, track and/or trend closed-loop cardiac resynchronization therapy using cardiac activation sequence information. Devices and methods involve sensing a plurality of composite cardiac signals using a plurality of electrodes, the electrodes configured for implantation in a patient. A source separation is performed using the sensed plurality of composite cardiac signals, producing one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences. A cardiac resynchronization therapy is adjusted using one or both of the one or more cardiac signal vectors and the signals associated with the one or more cardiac signal vectors. In further embodiments, the cardiac resynchronization therapy may be initiated, terminated, or one or more parameters of the resynchronization therapy may be altered.
摘要:
A system and method for pacing rate control in a cardiac rhythm management (CRM) system. The method includes acquiring a pressure signal representative of coronary venous pressure (CVP) from a pressure sensor implanted within a coronary vein of the patient and generating a CVP waveform from the pressure signal. A pacing stimulus is applied to the patient's heart, and the pacing rate is increased in response to increases in patient's metabolic demand. The CVP index is monitored during the pacing rate increase, and the CRM system detects a reduction in the patient's hemodynamic performance based on the CVP index and establishes a maximum rate setting based on the pacing rate corresponding to the reduction in the patient's hemodynamic performance.
摘要:
Systems and methods of managing features or functions of an implantable cardiac device involve forming a baseline evoked response template prior to delivery of defibrillation therapy to a patient's heart, and acquiring a post-shock evoked response signal subsequent to defibrillation therapy delivery. The baseline evoked response template is compared to the post-shock evoked response signal. A determination is made whether to enable, disable or adjust a cardiac device feature based on the comparison. The cardiac device feature may be a therapy feature, a monitoring feature, or a diagnostic feature.
摘要:
Methods and systems involve classifying the cardiac response to pacing using a multi-channel approach. Multiple cardiac response signals are sensed via multiple sense channels. Each sense channel comprises a distinct combination of electrodes and sensing circuitry. The cardiac response to the pacing pulse is classified based on the morphology of the cardiac response signals. Classifying the cardiac response involves discriminating between capture, fusion, non-capture, and non-capture with intrinsic activity.
摘要:
Systems and methods of managing features or functions of an implantable cardiac device involve forming a baseline evoked response template prior to delivery of defibrillation therapy to a patient's heart, and acquiring a post-shock evoked response signal subsequent to defibrillation therapy delivery. The baseline evoked response template is compared to the post-shock evoked response signal. A determination is made whether to enable, disable or adjust a cardiac device feature based on the comparison. The cardiac device feature may be a therapy feature, a monitoring feature, or a diagnostic feature.
摘要:
One embodiment of the present invention accounts for individual anatomical variation when evaluating optical nerve fiber measurements. In one aspect, contextual information is used to compensate or correct measurement data. In another aspect, reference coordinates are remapped for improved comparison or visualization. In one embodiment of this latter aspect, the method uses measurements of nerve fiber capacity and maps of nerve fiber retinal service to improve sensitivity and specificity in eye function metrics. In one instance, we use the birefringence of nerve fibers to determine the orientation of the fibers within the RNFL. Orientation of the fibers about the ONH is indicative of the service provided by the fibers and is used to improve the interpretation of thickness measurements of the nerve fiber layer. Normalized nerve fiber measurements about the optic nerve head improve specificity and sensitivity as compared to the standard model. These improvements are a result of partitioning the normative database or modifying the measurement data prior to comparison. Statistics on normalized measurements of nerve fiber bundles also show improvements in specificity and sensitivity.
摘要:
Methods and devices used to classify cardiac events based on morphological analysis of sensed signals are described. A signal comprising a cardiac signal component and a noise signal component is sensed. The sensed signal is processed to preferentially alter morphology of the cardiac signal component. The altered morphology of the cardiac signal component enhances detection of one or more features of the cardiac signal component. The features of the cardiac signal component are detected and the cardiac event is classified using the detected features. Processing the sensed signal may involve the use of adaptable signal processing parameters. For example, the signal processing parameters may be selected to accentuate one or more desirable features of the cardiac signal component or to mitigate one or more undesirable features of the cardiac signal component.
摘要:
Cardiac devices and methods involve the detection of cardiac signals features in adjacent classification intervals. Portions of the cardiac signal features detected in adjacent classification intervals are associated and are used to classify the cardiac response to a pacing pulse. Associating the portions of the cardiac signal features may be based on expected signal morphology.
摘要:
A utility greenhouse (10) has a frame (30) comprised of electrical metal tubing (EMT) sections. Main frame members (12) bear the majority of the building's load. Main frame members (12), long side members (14) and short side members (16) all embed into the ground and are shaped to extend vertically upward for a wall height distance then curve upwards and inward so that a pronounced rounded appearance for the frame (30) results. The main frame members (12) and the long frame members (14) intersect the short frame members (16). Ties (26) secure the intersecting frame members together. A continuous sheet plastic skin (24) overlies the frame. The skin (24) is held to the frame (30) at an outer cover brace (18), an inner cover brace (20), and through ties (26) which secure skin (24) to the long and short frame members (14, 16). A door (54) is formed by cutting the skin (24).