摘要:
Optimizing cardiac preload based on measured pulmonary artery pressure involves varying, for each repetition of an acute burst protocol, a parameter of pacing applied to a patient's heart during the acute burst protocol. Pulmonary artery pressure is measured during the repetitions of the acute burst protocol. The length of the repetitions is chosen so that the patient's baroreflex system does not adjust to the varied parameter of pacing during the repetitions of the acute burst protocol. An optimum ventricular preload is determined based on the measured pulmonary artery pressure. Pacing therapy is provided using a value of the parameter that is selected based on the determination of optimum ventricular preload.
摘要:
Optimizing cardiac preload based on measured pulmonary artery pressure involves varying, for each repetition of an acute burst protocol, a parameter of pacing applied to a patient's heart during the acute burst protocol. Pulmonary artery pressure is measured during the repetitions of the acute burst protocol. An optimum ventricular preload is determined based on the measured pulmonary artery pressure. Pacing therapy is provided using a value of the parameter that is selected based on the determination of optimum ventricular preload.
摘要:
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.
摘要:
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.
摘要:
Systems and methods for pacing the heart using resynchronization pacing delays that achieve improvement of cardiac function are described. An early activation pacing interval is calculated based on an optimal AV delay and an atrial to early ventricular activation interval between an atrial event and early activation of a ventricular depolarization. The early activation pacing interval for the ventricle is calculated by subtracting the measured AVEA from the calculated optimal AV delay. The early activation pacing interval is initiated responsive to sensing early activation of the ventricle and pacing is delivered relative to expiration of the early activation pacing interval.
摘要:
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.
摘要:
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.
摘要:
Method and systems related to monitoring right ventricular function during pacing by a cardiac rhythm management device are described. One or more pacing parameters are selected to provide cardiac resynchronization therapy. For example, the one or more pacing parameters may be selected to provide an optimal or improved therapy. The heart is paced using the selected pacing parameters. While pacing with the selected parameters, pressure is sensed via a pressure sensor disposed the pulmonary artery. The sensed pressure is analyzed to determine right ventricular function achieved during the pacing using the selected pacing parameters. A signal, such as an alert signal or control signal, is generated based on the right ventricular function achieved during the pacing.
摘要:
A system and method for detecting and treating symptoms of early decompensation utilizing a cardiac rhythm management. The system applies an electrical stimulus to the patient's heart at a first set of pacing parameters including a lower rate limit (LRL) setting, and acquires a coronary venous pressure (CVP) signal from a pressure sensor implanted in a coronary vein of the patient. An average coronary venous end diastolic pressure (CV-EDP) value is calculated from the CVP signal. The system monitors the average CV-EDP value over a predetermined interval, and dynamically adjusts the LRL setting responsive to the detection of a first or a second predetermined event based on the average CV-EDP value.
摘要:
Various embodiments of an implantable system for delivering therapy comprise at least one of a heat sink or source to either reduce or increase temperature of excitable tissue, a pulse generator and at least one stimulation electrode to deliver electrical stimulation to excitable tissue, a memory and a controller. The memory has instructions for performing at least one stimulation routine and at least one thermal routine, and further has integration instructions for integrating the thermal routine(s) with the stimulation routine(s). The controller is configured to operate on the instructions to perform the stimulation routine(s) using the pulse generator and the at least one stimulation electrode, to perform the thermal routine(s) using the heat sink or the heat source, and to operate on the integration instructions to integrate thermal routine(s) with the stimulation routine(s).