Patent ID: 7666144

Claim:
A method for determining an average left atrial pressure (LAP) using a cardiac cycle waveform signal, the method comprising: converting, by an analog-to-digital converter of an apparatus, a cardiac cycle waveform signal of a patient into a digital cardiac signal, the digital cardiac signal comprising a plurality of digital cardiac signal values; selecting, from a buffer system of the apparatus, two or more digital cardiac signal values from a first interval of the digital cardiac signal; fitting, by a processing unit of the apparatus, a nonlinear function to match the two or more digital cardiac signal values within the first interval; extrapolating, by the processing unit, a plurality of values of the nonlinear function for a second interval of the nonlinear function, the second interval of the nonlinear function corresponding to an interval of the digital cardiac signal that is different from the first interval; and determining, by the apparatus, one or more average left atrial pressure (LAP) values based on a mean value of the plurality of values of the extrapolated nonlinear function over a portion of the second interval.