System for processing physiological data

A system for computing a parameter value for a segment of a cardiac-related signal, the system comprising:

• a computer circuit configured and arranged to
• identify at least one cardiac cycle within said segment,
• identify at least one feature point of a signal wave within the at least one cardiac cycle, and
• for the at least one identified feature point, compute the estimate an estimate of at least one of signal energy and noise energy for a cardiac cycle subsegment containing the at least one identified feature point, wherein computing at least one of the signal energy and noise energy includes
• decomposing said cardiac-related signal into subcomponents,
• identifying a subsegment of the at least one cardiac cycle that includes the at least one feature point,
• when computing signal energy, estimating the signal energy by combining subcomponents within the subsegment that together contain a majority of the signal energy, and
• when computing noise energy, estimating the noise energy by combining residual subcomponents that are not combined in estimating the signal energy;
• determine a validity characteristic of the at least one feature point based upon the estimate;
• and
• compute a parameter value based upon the determined validity characteristics of the at least one feature point.

An article of manufacture, comprising:

• a processor-readable storage medium configured with configuration data that when executed by a processor, cause the processor to perform steps including:
• identify cardiac cycles within a segment of a cardiac-related signal,
• identify at least one feature point within said cardiac cycles,
• for each of the identified feature points, compute a signal-to-noise ratio representative of the ratio of signal energy to noise energy for a cardiac cycle subsegment containing the identified feature point, and determine a validity characteristic of the feature point as a function of said signal-to-noise ratio, and
• compute a parameter value by combining feature points contained within said segment based upon the determined validity characteristics of the feature points.

An apparatus comprising:

• a computer circuit configured and arranged to
• identify at least one cycle within an electrocardiogram signal,
• identify a feature point within a subsegment of the at least one cycle by
• decomposing said electrocardiogram signal into subcomponents,
• computing an emphasis signal using one or more subcomponents that together contain at least a majority of energy of a signal wave within the subsegment, and
• evaluating the emphasis signal to identify the feature point, and
• compute a validity characteristic of the feature point based upon at least one of estimated signal energy and estimated noise energy within the subsegment.

An apparatus comprising:

• a computer circuit configured and arranged to
• identify at least one cycle within an electrocardiogram signal,
• identify a feature point of a wave of the electrocardiogram signal within a subsegment of the at least one cycle,
• compute at least one of estimated signal energy and estimated noise energy in the subsegment by
• decomposing said electrocardiogram signal into subcomponents,
• identifying a cycle,
• identifying said subsegment containing said feature point,
• when estimating signal energy, combining wave subcomponents from within said subsegment that, combined, represent at least a majority of the energy of said wave, and
• when estimating noise energy, combining residual ones of the wave subcomponents that have not been combined in estimating the signal energy, and
• compute a validity characteristic of the feature point based upon at least one of estimated signal energy and the estimated noise energy within the subsegment.

An article of manufacture, comprising:

• a processor-readable storage medium configured with configuration data that when executed by a processor, cause the processor to perform steps including:
• identify cycles within a segment of a pseudoperiodic physiological signal,
• identify at least one feature point within said cycles,
• for each of the identified feature points, compute an estimate of signal energy and noise energy in a cycle subsegment containing the identified feature point, and determine a validity characteristic of the feature point as a function of the relationship of said signal and noise energy estimates, and
• compute a parameter value by combining feature points based upon the determined validity characteristics of the feature points.