Patent ID: 6368283
Filing Date: 2002-04-09
Classification: A61B

Abstract:
Method of estimating systolic and mean pulmonary artery pressures of a patient, comprising the steps of:(a) producing an electric signal xs(t) representative of heart sounds of the patient; (b) extracting second heart sound S2(t) from the signal produced in step (a); (c) extracting pulmonary and aortic components P2(t) and A2(t) from S2(t); (d) extracting a signal representative of mean cardiac interval from the signal produced in step (a); (e) correlating the pulmonary and aortic components P2(t) and A2(t) to obtain a cross correlation function; (f) measuring a splitting interval as the time of occurrence of the maximal value of the cross correlation function obtained in step (e); (g) producing a normalized splitting interval by dividing the splitting interval obtained in step (f) by the mean cardiac interval obtained in step (d); and (h) estimating the systolic and mean pulmonary artery pressures using of predetermined regressive functions, said predetermined regressive functions describing relationships between the normalized splitting interval and the systolic and mean pulmonary artery pressures.