Objective To explore the generalization and application of R-W1 through the phase analysis of Wave intensity technique.Methods The phases of R-W1 of 66 healthy adults were detected by Aloka Prosound α10 color Doppler uhrasound.Results There were all statistical significances in the time difference of R-W1 in left and right common carotid arteries and right brachial artery(P＜0.01),in the pressure wave conductive time in left and right common carotid arteries(P＜0.05),in right brachial artery and both sides of common carotid arteries(P＜0.01).There were no statistical significances in the time from the starting point to the culminate point of W1 in left and right common carotid arteries.There were statistical significances in the time from the starting point to the culminate point of W1 in right brachial artery and both sides of common carotid arteries(P＜0.05).Conclusions"R-W1 almost equals to pre-ejection period"as reported by literatures actually involves three phases which respectively are isovolumetric contraction time of left ventricle,pressure wave conductive time and time from the starting point to the culminate point of W1.The factor of pressure wave conductive time should be considered when evaluating diseases in clinic.The pre-ejection time should be the time from the culminate point of R wave in ECG to the starting point of W1 and the time from the starting point to the culminate point of W1 should not be involved in.

Objective To evalute the clinical application of the new technique of instantaneous wave intensity(WI) through the correlative analysis of instantaneous acceleration wave intensity(W1) and Tei index. Methods The correlation of the intensity of W1 (the apogee of W1) and Tei index of 66 healthy adults were analyzed by Prosound a10 color Doppler ultrasonograph. Results There were positive correlations in pressure and caliber between the common carotid arteries of both sides in 66 cases of healthy adults (P <0.01). There were negative correlations respectively between the pressure of W1 of left and right common carotid arteries and Tei index (P <0.05),and there were the same in caliber (P <0.01), mean pressure (P <0.05) and mean caliber (P <0.01). Conclusions W1 is negatively correlated with Tei index and can be an index in judging the systolic function.

Denoising methods based on wavelet analysis and empirical mode decomposition cannot essentially track and eliminate noise, which usually cause distortion of heart sounds. Based on this problem, a heart sound denoising method based on improved minimum control recursive average and optimally modified log-spectral amplitude is proposed in this paper. The proposed method uses a short-time window to smoothly and dynamically track and estimate the minimum noise value. The noise estimation results are used to obtain the optimal spectrum gain function, and to minimize the noise by minimizing the difference between the clean heart sound and the estimated clean heart sound. In addition, combined with the subjective analysis of spectrum and the objective analysis of contribution to normal and abnormal heart sound classification system, we propose a more rigorous evaluation mechanism. The experimental results show that the proposed method effectively improves the time-frequency features, and obtains higher scores in the normal and abnormal heart sound classification systems. The proposed method can help medical workers to improve the accuracy of their diagnosis, and also has great reference value for the construction and application of computer-aided diagnosis system.
Algorithms ; Heart Sounds ; Humans ; Signal Processing, Computer-Assisted ; Signal-To-Noise Ratio ; Wavelet Analysis