Method and apparatus for using an optical hemodynamic sensor to identify an unstable arrhythmia

摘要

A medical device identifies a hemodynamically unstable arrhythmia based upon optical hemodynamic sensor signals. The optical hemodynamic sensor includes a light source for transmitting light corresponding to first and second wavelengths through a blood perfused tissue of a patient and a light detector for generating optical signals corresponding to an intensity of the detected light at the first and second wavelengths. At a low motion period for the patient, optical signals are obtained from the optical hemodynamic sensor and are analyzed to determine a baseline motion level for the patient. Subsequent signals obtained from the optical hemodynamic sensor are compared to the baseline motion levels, with only those signals corresponding to periods where motion does not exceed the baseline level of motion being further analyzed to determine if they are consistent with a hemodynamically unstable arrhythmia.