摘要:
A method and apparatus for detection of changes in physiologic parameters of a patient that includes generating measured physiologic parameters, generating an adaptive baseline trend of the measured physiologic parameters corresponding to a first time period, generating a short term trend of the measured physiologic parameters corresponding to a second time period less than the first time period, and generating a metric of physiologic parameter change between the adaptive baseline trend and one of a most recent measured physiologic parameter and the short term trend of the measured physiologic parameters.
摘要:
The present invention provides a technique for verifying pacing capture of a ventricular chamber, particularly to ensure desired delivery of a ventricular pacing regime (e.g., cardiac resynchronization therapy or “CRT”). The invention also provides for ventricular capture management by delivering a single ventricular pacing stimulus and checking inter-ventricular conduction during a temporal window to determine if the ventricular pacing stimulus captured the chamber. If a loss-of-capture (LOC) signal results from the capture management testing, then the characteristics of the applied pacing pulses are modified and the conduction test repeated. In the event that the LOC signal persists, a pacing mode-switch to an atrial-based pacing therapy and/or non-bi-ventricular pacing regimen can be implemented.
摘要:
The disclosure provides methods and apparatus of left ventricular pacing including automated adjustment of a atrio-ventricular (AV) pacing delay interval and intrinsic AV nodal conduction testing. It includes—upon expiration or reset of a programmable AV Evaluation Interval (AVEI)—performing the following: temporarily increasing a paced AV interval and a sensed AV interval and testing for adequate AV conduction and measuring an intrinsic atrio-ventricular (PR) interval for a right ventricular (RV) chamber. Thus, in the event that the AV conduction test reveals a physiologically acceptable intrinsic PR interval then storing the physiologically acceptable PR interval in a memory structure (e.g., a median P-R from one or more cardiac cycles). In the event that the AV conduction test reveals an AV conduction block condition or if unacceptably long PR intervals are revealed then a pacing mode-switch to a bi-ventricular (Bi-V) pacing mode occurs and the magnitude of the AVEI is increased.
摘要:
A method of operating a cardiac pacing device that optimizes the mechanical heart rate using coordinated potentiation therapy while maximizing the opportunity for intrinsic AV conduction to occur. The method may include adjusting the timing of extra stimulus intervals during coupled or paired pacing to promote AV conduction and to effect changes in rate according to certain embodiments of the invention. Other embodiments may include adjusting the atrial pacing rate to achieve a desired target rate consistent with AV conduction. A mode switch to a dual-chamber pacing mode may be provided according to certain embodiments of the invention to ensure a ventricular rate that meets or exceeds a minimum mechanical rate.
摘要:
An extra-systolic stimulation (ESS) therapy addresses cardiac dysfunction including heart failure. ESS therapy employs atrial and/or ventricular extra-systoles via pacing-level stimulation to a heart. These extra-systoles must be timed correctly to achieve beneficial effects on myocardial mechanics (efficacy) while maintaining an extremely low level of risk of arrhythmia induction and excellent ICD-like arrhythmia sensing and detection (security). The present invention relates to therapy delivery guidance and options for improved ESS therapy delivery. These methods may be employed individually or in combinations in an external or implantable ESS therapy delivery device.
摘要:
The above-described methods and apparatus are believed to be of particular benefit for patients suffering heart failure including cardiac dysfunction, chronic HF, and the like and all variants as described herein and including those known to those of skill in the art to which the invention is directed. It will understood that the present invention offers the possibility of monitoring and therapy of a wide variety of acute and chronic cardiac dysfunctions. The current invention provides systems and methods for delivering therapy for cardiac hemodynamic dysfunction via the innervated myocardial substrate receives one or more discrete pulses of electrical stimulation during the refractory period of said innervated myocardial substrate.
摘要:
The present invention provides a technique for verifying pacing capture of a ventricular chamber, particularly to ensure desired delivery of a ventricular pacing regime (e.g., “CRT”). The invention also provides ventricular capture management by delivering a single ventricular pacing stimulus and checking inter-ventricular conduction during a temporal window to determine if the stimulus captured. If a loss-of-capture (LOC) signal results from the capture management testing, then the applied pacing pulses are modified and the conduction test repeated. If LOC, an alert message can issue. Other aspects include: use of a trend of A-RV/LV and LV-RV timing intervals to monitor changes in the patient's heart conduction properties; bi-ventricular verification test and search—while still pacing BiV by detecting latent sense; single-V pacing threshold search, use of timing of sense in other V chamber to establish capture and LOC windows; (iv) use of a premature V pace rather than short AV interval if VV cannot be discriminated from AV; (v) option to run a threshold search only if the Bi-ventricular verification test fails.
摘要:
The invention provides methods and apparatus for determining in a non-tracking pacing mode (e.g., DDI/R, VVI/R) whether a ventricular pacing stimulus is capturing a paced ventricle, including some or all of the following aspects. For example, increasing a ventricular pacing rate a nominal amount to an overdrive pacing rate higher than a most recent heart rate and evaluating a conduction interval from a first pacing ventricle to a second sensing ventricle and then continuing to monitor the underlying rate to ensure that a threshold testing pacing rate will not exceed a predetermined minimum interval and providing pacing stimulation to the first ventricle and sensing the second ventricle to determine whether the pacing stimulation to the first ventricle was one of sub-threshold and supra-threshold. The methods and apparatus are especially useful in conjunction with ensuring actual delivery of a ventricular pacing regime (e.g., cardiac resynchronization therapy or “CRT”).
摘要:
A cardiac rhythm management system includes an implantable medical device capable of delivering cardiac therapy and sensing an EGM. The implantable medical device undergoes threshold testing and transmits testing data to a computer via a remote monitor.
摘要:
The present invention relates to the secure delivery of an extra-systolic stimulation (ESS) therapy to treat cardiac dysfunction that employs atrial and/or ventricular extra-systoles via pacing-like stimulation of the heart. These extra-systoles must be timed correctly to achieve beneficial effects on myocardial mechanics (benefit) while maintaining an extremely low level of risk of arrhythmia induction and excellent ICD-like arrhythmia sensing and detection (security). Further experience with ESS has led to improved implementation methods that depend on better blanking, ESS stimulation timing (of an “extra-systolic interval” or ESI), and ESS therapy delivery options and guidance. These methods may be employed individually or in combinations in an external or implantable ESS therapy delivery device.