Patent ID: 10159445

Abstract:
Embodiments of the present invention provide an improved transformation method whereby the peripheral pulse waveform is filtered to separate different phases which make up the waveform. The separate phases are transformed before being re-combined to provide an estimated intra-arterial transfer function. For example, in one embodiment the peripheral pulse waveform is filtered by a first high pass filter, and a copy of the peripheral pulse waveform filtered by a second high pass filter, having a different cut-off frequency. The two filtered waveforms may then be further processed, for example by being added back to original wave-form, and are then multiplexed together in a time division manner to provide a final waveform. For example, the part of the first filtered waveform corresponding to the systolic phase may be combined with the part of the second filtered waveform corresponding to the diastolic phase to produce the final waveform, and the respective filter cut-off frequencies may be chosen to extract characteristics of the respective phases of the heart.