Aiming at the problems of obscure clinical auscultation features of pulmonary hypertension associated with congenital heart disease and the complexity of existing machine-aided diagnostic algorithms,an algorithm based on the statistical characteristics of the high-frequency components of the second heart sound signal is proposed.Firstly,an endpoint detection adaptive segmentation method is employed to extract the second heart sounds.Subsequently,the high-frequency component of the heart sound is decomposed using the discrete wavelet transform.Statistical features including the Hurst exponent,Lempel-Ziv information and sample entropy are extracted from this component.Finally,the extracted features are utilized to train an extreme gradient boosting algorithm(XGBoost)classifier,which achieves an accuracy of 80.45%in triple classification.Notably,this method eliminates the need for a noise reduction algorithm,allows for swift feature extraction,and achieves effective multi-classification using only three features.It is promising for early screening of pulmonary hypertension associated with congenital heart disease.