Parametric modeling of diastolic heart sounds before and after angioplasty

Isolated diastolic heart sounds were analyzed using the autoregressive (AR) and autoregressive moving average (ARMA) methods as part of an ongoing program to develop a noninvasive procedure for the detection of coronary artery disease. Model parameters were used to estimate whether the recordings were made before or after the coronary lesions were enlarged through angioplastic surgery. Using spectral characteristics along with changes in zero location, a blind judgment was made, appropriately, for all ten patients in the initial study