摘要:
A system and method for managing preload reserve and tracking the inotropic state of a patient's heart. The S1 heart sound is measured as a proxy for direct measurement of stroke volume. The S3 heart sound may be measured as a proxy for direct measurement of preload level. The S1-S3 pair yield a point on a Frank Starling type of curve, and reveal information regarding the patient's ventricular operating point and inotropic state. As an alternative, or in addition to, measurement of the S3 heart sound, the S4 heart sound may be measured or a direct pressure measurement may be made for the sake of determining the patient's preload level. The aforementioned measurements may be made by a cardiac rhythm management device, such as a pacemaker or implantable defibrillator.
摘要:
A system and method to sense heart sounds with one or more implantable medical devices according to one or more parameters. The system alters one or more of the parameters as a function of one or more triggering events. The system then senses heart sounds with the one or more implantable medical devices according to at least the one or more altered parameters.
摘要:
Various system embodiments comprise a stimulator adapted to deliver a stimulation signal for a heart failure therapy, a number of sensors adapted to provide at least a first measurement of a heart failure status and a second measurement of the heart failure status, and a controller. The controller is connected to the stimulator and to the number of sensors. The controller is adapted to use the first and second measurements to create a heart failure status index, and control the stimulator to modulate the signal using the index. Other aspects and embodiments are provided herein.
摘要:
An implantable device and method for monitoring S1 heart sounds with a remotely located accelerometer. The device includes a transducer that converts heart sounds into an electrical signal. A control circuit is coupled to the transducer. The control circuit is configured to receive the electrical signal, identify an S1 heart sound, and to convert the S1 heart sound into electrical information. The control circuit also generates morphological data from the electrical information. The morphological data relates to a hemodynamic metric, such as left ventricular contractility. A housing may enclose the control circuit. The housing defines a volume coextensive with an outer surface of the housing. The transducer is in or on the volume defined by the housing.
摘要:
A cardiac rhythm management system provides a phonocardiographic image indicative of a heart's mechanical events related to hemodynamic performance. The phonocardiographic image includes a stack of acoustic sensor signal segments representing multiple cardiac cycles. Each acoustic sensor signal segment includes heart sounds indicative of the heart's mechanical events and representations of the heart's electrical events. The stack of acoustic sensor signal segments are aligned by a selected type of the heart's mechanical or electrical events and are grouped by a cardiac timing parameter for presentation.
摘要:
An apparatus comprises an implantable sensor and a signal analyzer circuit communicatively coupled to the implantable sensor. The implantable sensor is configured for coupling to an implantable lead and the implantable sensor provides an electrical vibration sensor signal representative of mechanical vibration of the implantable lead. The signal analyzer circuit is configured to determine a baseline of the vibration sensor signal, detect a change in the vibration sensor signal from the baseline vibration sensor signal, and provide an indication of the change to a user or process.
摘要:
The health state of a subject is automatically evaluated or predicted using at least one implantable device. In varying examples, the health state is determined by sensing or receiving information about at least one physiological process having a circadian rhythm whose presence, absence, or baseline change is associated with impending disease, and comparing such rhythm to baseline circadian rhythm prediction criteria. Other chronobiological rhythms beside circadian may also be used. The baseline prediction criteria may be derived using one or more past physiological process observation of the subject or population of subjects in a non-disease health state. The prediction processing may be performed by the at least one implantable device or by an external device in communication with the implantable device. Systems and methods for invoking a therapy in response to the health state, such as to prevent or minimize the consequences of predicted impending heart failure, are also discussed.
摘要:
Methods and systems for assessing pulmonary or systemic vascular resistance in a patient using pressure measurements are disclosed. An illustrative method of measuring pulmonary vascular resistance includes electrically inducing a retrograde pressure pulse within the heart, sensing at least one arterial pressure parameter in response to the retrograde pressure pulse using a pressure sensor located within a pulmonary artery, and computing a value of the pulmonary vascular resistance using the at least one sensed arterial pressure parameter. Data from multiple pulmonary vascular resistance assessments can be taken over an extended period of time within the patient to aid in detecting an underlying cardiac or pulmonary condition such as cardiogenic pulmonary edema.
摘要:
A system to monitor heart sounds. The system comprises an implantable heart sound sensor operable to produce an electrical signal representative of at least one heart sound, a heart sound sensor interface circuit coupled to the heart sound sensor to produce a heart sound signal, an implantable posture sensor operable to produce an electrical signal representative of a patient's posture, and a controller circuit, coupled to the heart sound sensor interface circuit and the posture circuit. The controller circuit is operable to measure at least one heart sound in correspondence with at least one sensed patient posture.
摘要:
A system and method for managing preload reserve and tracking the inotropic state of a patient's heart. The S1 heart sound is measured as a proxy for direct measurement of stroke volume. The S3 heart sound may be measured as a proxy for direct measurement of preload level. The S1-S3 pair yield a point on a Frank Starling type of curve, and reveal information regarding the patient's ventricular operating point and inotropic state. As an alternative, or in addition to, measurement of the S3 heart sound, the S4 heart sound may be measured or a direct pressure measurement may be made for the sake of determining the patient's preload level. The aforementioned measurements may be made by a cardiac rhythm management device, such as a pacemaker or implantable defibrillator.