摘要:
Cardiac monitoring and/or stimulation methods and systems employing dyspnea measurement. An implantable cardiac device may sense transthoracic impedance and determine a patient activity level. An index indicative of pulmonary function is implantably computed to detect an episode of dyspnea based on a change, trend, and/or value exceeding a threshold at a determined patient activity level. Trending one or more pulmonary function index values may be done to determine a patient's pulmonary function index profile, which may be used to adapt a cardiac therapy. A physician may be automatically alerted in response to a pulmonary function index value and/or a trend of the patient's pulmonary index being beyond a threshold. Computed pulmonary function index values and their associated patient's activity levels may be stored periodically in a memory and/or transmitted to a patient-external device.
摘要:
Approaches for adjusting the pacing energy delivered by a pacemaker are provided. Adjusting the pacing energy involves performing a plurality of capture threshold tests, each capture threshold test measuring a capture threshold of the heart. One or more measured captured thresholds are selected, including at least one capture threshold that is higher relative to other measured capture thresholds acquired by the plurality of capture threshold tests. The pacing energy is adjusted based on the one or more selected capture thresholds.
摘要:
Methods and devices for classifying a cardiac response to pacing involve establishing a retriggerable cardiac response classification window. A first cardiac response classification window is established subsequent to delivery of a pacing pulse. A cardiac signal following the pacing stimulation is sensed in the first classification window. A second cardiac response classification may be triggered if a trigger characteristic is detected in the first classification window. The cardiac signal is sensed in the second classification window if the second classification window is established. The cardiac response to the pacing stimulation is determined based on characteristics of the cardiac signal. The cardiac response may be determined to be one of a captured response, a non-captured response; a non-captured response added to an intrinsic beat, and a fusion/pseudofusion beat, for example.
摘要:
Methods and devices for classifying a cardiac response to pacing involve establishing a retriggerable cardiac response classification window. A first cardiac response classification window is established subsequent to delivery of a pacing pulse. A cardiac signal following the pacing stimulation is sensed in the first classification window. A second cardiac response classification may be triggered if a trigger characteristic is detected in the first classification window. The cardiac signal is sensed in the second classification window if the second classification window is established. The cardiac response to the pacing stimulation is determined based on characteristics of the cardiac signal. The cardiac response may be determined to be one of a captured response, a non-captured response, a non-captured response added to an intrinsic beat, and a fusion/pseudofusion beat, for example.
摘要:
Approaches for adjusting the pacing energy delivered by a pacemaker are provided. Adjusting the pacing energy involves performing a plurality of capture threshold tests, each capture threshold test measuring a capture threshold of the heart. One or more measured captured thresholds are selected, including at least one capture threshold that is higher relative to other measured capture thresholds acquired by the plurality of capture threshold tests. The pacing energy is adjusted based on the one or more selected capture thresholds.
摘要:
A method and apparatus for cardiac stimulation for addressing vasovagal syncope incorporates a detection algorithm in which a precipitous rate drop from a pre-existing average intrinsic heart rate value to a lower rate limit is sensed and if the patient is awake and the intrinsic rate remains below the lower rate limit for a predetermined number of beats, the patient's heart is paced at a rate that is a programmed differential above the prior average intrinsic rate for a second programmed time interval, at the conclusion of which the pacing rate is gradually decreased to the average heart rate existing prior to the sudden rate drop or to the lower rate limit.
摘要:
Methods and devices for classifying a cardiac response to pacing involve establishing a retriggerable cardiac response classification window. A first cardiac response classification window is established subsequent to delivery of a pacing pulse. A cardiac signal following the pacing stimulation is sensed in the first classification window. A second cardiac response classification may be triggered if a trigger characteristic is detected in the first classification window. The cardiac signal is sensed in the second classification window if the second classification window is established. The cardiac response to the pacing stimulation is determined based on characteristics of the cardiac signal. The cardiac response may be determined to be one of a captured response, a non-captured response, a non-captured response added to an intrinsic beat, and a fusion/pseudofusion beat, for example.
摘要:
Methods and systems for detecting noise in cardiac pacing response classification processes involve determining that a cardiac response classification is possibly erroneous if unexpected signal content is detected. The unexpected signal content may comprise signal peaks that have polarity opposite to the polarity of peaks used to determine the cardiac response to pacing. Fusion/noise management processes include pacing at a relatively high energy level until capture is detected after a fusion, indeterminate or possibly erroneous pacing response classification is made. The relatively high energy pacing pulses may be delivered until capture is detected or until a predetermined number of paces are delivered.
摘要:
Methods and devices for classifying a cardiac response to pacing involve establishing a retriggerable cardiac response classification window. A first cardiac response classification window is established subsequent to delivery of a pacing pulse. A cardiac signal following the pacing stimulation is sensed in the first classification window. A second cardiac response classification may be triggered if a trigger characteristic is detected in the first classification window. The cardiac signal is sensed in the second classification window if the second classification window is established. The cardiac response to the pacing stimulation is determined based on characteristics of the cardiac signal. The cardiac response may be determined to be one of a captured response, a non-captured response; a non-captured response added to an intrinsic beat, and a fusion/pseudofusion beat, for example.