摘要:
Methods and devices for determining optimal Atrial to Ventricular (AV) pacing intervals and Ventricular to Ventricular (VV) delay intervals in order to optimize cardiac output. Impedance, preferably sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change.
摘要:
A method and system for improving or optimizing the collection of data from and the delivery of therapy to a patient by an implantable medical device (IMD) is disclosed which uses information about the patient's respiratory cycle.
摘要:
Methods and devices for determining optimal Atrial to Ventricular (AV) pacing intervals and Ventricular to Ventricular (VV) delay intervals in order to optimize cardiac output. Impedance, preferably sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change.
摘要:
Methods and devices for determining optimal Atrial to Ventricular (AV) pacing intervals and Ventricular to Ventricular (VV) delay intervals in order to optimize cardiac output. Impedance, preferably sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change.
摘要:
Methods and devices for determining optimal Atrial to Ventricular (AV) pacing intervals and Ventricular to Ventricular (VV) delay intervals in order to optimize cardiac output. Impedance, preferably sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change.
摘要:
Impedance, e.g. sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change. Other methods vary the AA interval to maximize impedance change over the entire cardiac cycle or during the atrial cycle.
摘要:
Various techniques for measuring cardiac cycle length and pressure metrics based on pulmonary artery pressures are described. One example method described includes identifying a point within a derivative signal of a cardiovascular pressure signal without reference to electrical activity of a heart, initiating a time window from the identified point in the derivative signal, identifying a point within the cardiovascular signal within the time window, and determining at least one of a systolic pressure or diastolic pressure based on the identified point.
摘要:
The present invention provides an apparatus for detecting and monitoring obstructive sleep apnea. The apparatus measures sinus tachycardia and a change in the atrial-ventricular conduction, and includes a controller for receiving the measurement of the sinus tachycardia and the change in the atrial-ventricular conduction to detect obstructive sleep apnea based upon the sinus tachycardia and the change in the atrial-ventricular conduction.
摘要:
An implantable medical device and associated method detect obstructed inspiration by monitoring an blood pressure signal. A respiration signal is monitored and a phase of respiratory inspiration is detected from the respiration signal. A trend in the pressure signal is measured during the inspiration phase. Obstructed inspiration for the inspiration phase is detected in response to the measured the trend.
摘要:
Apparatus using one or more modes of statistical analysis with one or more monitored parameters of a patient's heart to identify and/or assess arrhythmias. Through use of the one or more modes of statistical analysis, a medical professional can be aided during evaluation of patient data for diagnosis of the patient. At least one of the monitored parameters may include one or more values used representatively for storage intervals of a selected length. As such, for each storage interval, a value may be determined for the one monitored parameter occurring at an upper percentile and a lower percentile. In addition, a median value may be determined for the one monitored parameter for each storage interval. Over a plurality of the storage intervals, these determined values can be used in one or more modes of statistical analysis to better identify and assess the arrhythmias.