摘要:
A method of controlling pulmonary capillary pressure is disclosed which includes increasing the output of a first ventricle (V1) (e.g., a left ventricle) relative to second ventricle (e.g., right ventricle) by increasing the magnitude of a post extrasystolic potentiation (PESP) therapy effect in the first ventricle relative to the magnitude of a PESP therapy effect produced in the second ventricle. In certain embodiments of the invention, this may be accomplished by adjusting the extra-stimulus interval (ESI) in either or both of the left ventricle and the right ventricle, for example.
摘要:
A method and apparatus is provided for determining whether a current atrial-ventricular (AV) delay during cardiac pacing is appropriate for proper mechanical coupling of the atrium and ventricle. If proper mechanical coupling is determined to not exist, an additional atrial contraction is induced within the same ventricular cycle to maintain atrial-ventricular mechanical coupling.
摘要:
A system and method for detecting and classifying cardiac arrhythmias based on cardiac pressure signals or the combination of cardiac electrical and cardiac pressure signals. A cardiac electrogram signal is sensed to derive a cardiac rate from which an arrhythmia detection is made when the cardiac rate meets arrhythmia detection criteria. An intracardiac pressure signal is sensed to derive an indicator of tachycardia based on an analysis of the pressure signal in either the time domain or frequency domain. The detected arrhythmia is classified as tachycardia or fibrillation based on the tachycardia indicator wherein the tachycardia indicator is compared to tachycardia detection criteria and the arrhythmia is classified as tachycardia if tachycardia detection criteria are met and the arrhythmia is classified as fibrillation if the tachycardia detection criteria are not met.
摘要:
A method and apparatus is provided for determining whether a current atrial-ventricular (AV) delay during cardiac pacing is appropriate for proper mechanical coupling of the atrium and ventricle. If proper mechanical coupling is determined to not exist, an additional atrial contraction is induced within the same ventricular cycle to maintain atrial-ventricular mechanical coupling.
摘要:
An implantable medical device and associated method deliver a therapy to an autonomic nerve. The therapy delivery includes delivering therapeutic low frequency (LF) electrical stimulation pulses to the autonomic nerve and delivering a high frequency electrical signal to the autonomic nerve during the LF frequency stimulation pulse delivery. The high frequency stimulation signal blocks activation of autonomic nerve fibers innervating a non-targeted tissue during the therapeutic LF stimulation pulse delivery.
摘要:
Implantable pulse generators (IPGs) are adapted to deliver stimulation to refractory myocardial tissue. An IPG nominally delivers one to six monophasic stimulation pulses. Because monophasic stimulation tends to accumulate polarization, a programmable blanking period of between about 20 milliseconds (ms) and about 300 ms is implemented (subsequent to delivery of the last pulse in a RPS pulse train) to allow recovery from polarization. The stimulation pulse width is about 0.03 ms to about 1.6 ms and voltage amplitude of 0.5 volts to 8 volts at about 50 Hz. The amplitude of electrical current of the stimulation pulses is less than or equal to approximately 50 milliamps. The pulses are delivered to multiple sites within a cardiac chamber and device performance and/or diagnostic information can be stored within a memory structure and reviewed to confirm delivery of a desired therapy regimen.
摘要:
Refractory period stimulation (RPS) disclosed herein includes apparatus and methods to enhance cardiac performance by delivering monophasic stimulation pulses during the refractory period. The disclosure describes several system level improvements to RPS that include one or more of the following: (i) Delivery of RPS therapy pulses at multiple sites in an automatically alternating way to avoid increasing demand at any one location for prolonged periods of time. (ii) Delivery of RPS therapy pulses at multiple sites to determine one or more optimal electrode configurations for chronic RPS therapy delivery. (iii) Use of separate electrode(s) for sensing ventricular activity to properly time and adjust the application of RPS thereby avoiding limitations associated with electrode polarization that occurs due to the amount of energy delivered during the RPS. (iv) Use of a relatively long active recharge pulse at the RPS stimulation electrodes to remove the undesirable effects of polarization.
摘要:
A method and device for delivering cardiac stimulation that includes a first electrode, positioned within a first chamber of a heart, sensing cardiac signals associated with the first chamber and capable of delivering stimulation to the first chamber, and a second electrode, positioned within a second chamber of the heart, sensing cardiac signals associated with the second chamber and capable of delivering stimulation to the second chamber. A processing unit processes the sensed signals and controls the stimulation delivery via the first electrode and the second electrode, determining whether a predetermined rhythm is detected in the first chamber, and delivering high-frequency burst pacing to the first chamber in response to a predetermined rate being sensed in the second chamber during the predetermined rhythm.
摘要:
A method of performing a medical procedure, such as surgery, is provided. A nerve is stimulated to adjust the beating of the heart to a first condition, such as a stopped or slowed condition. The medical procedure is performed on the heart or another organ. The stimulation of the nerve is stopped to adjust the beating of the heart to a second condition, such as a beating condition. The heart itself may also be stimulated to a beating condition, such as by pacing. The stimulation of the nerve may be continued to allow the medical procedure to be continued. Systems and devices for performing the medical procedure are also provided.
摘要:
A method of stimulation therapy and an apparatus for providing the therapy which addresses cardiac dysfunction including heart failure. The therapy employs atrial pacing pulses delivered to a heart after the atrial refractory period and timed so that they will not cause a ventricular contraction. These atrial pacing are timed to achieve beneficial effects on myocardial mechanics (efficacy) while maintaining an extremely low level of risk of arrhythmia induction. These methods may be employed individually or in combinations in an external or implantable ESS therapy delivery device.