In this paper,heart rate (HR) and heart rate variability (HRV) are extracted from ECG,and the five indexes in both time and frequency domains are analyzed.The result shows that the standard deviation (SDNN) of R-R intervals,the value of total power (TP),the power value of low frequency (LF) of HRV and the value of LF/HF increase obviously,while the power value of high frequency (HF) decreases markedly after fatigue.The physical fatigue level is classified according to the rate of increase and decrease of the indexes above.It is suggested that these five ECG indexes be used to reflect and evaluate the degree of physical fatigue quantitatively.

BACKGROUND: Cardiac reserve indicators obtained under quiescent condition are used as evaluating index for cardiac reserve functions. However, most important aspect of cardiac dysfunction in heart failure is not the depressed cardiac performance noted at basal resting states, but rather the loss of cardiac reserve. OBJECTIVE: To develop a data processing and information management system for detecting cardiac reserve indicator with the widely used B mode ultrasound instrument in the ultrasonography field, and to provide guidance for B mode ultrasound instrument perfection. METHODS: General B mode ultrasound instrument as peripherals was connected with the pc by image acquisition card; ultrasound heart image diagnosis and management system including professional heart image acquisition and process and perfect data bank was develop. RESULTS AND CONCLUSION: An efficient and flexible mini picture archiving and communication system system was achieved, which realized image enhancement, geometric parameter measuring, convenient diagnosis report output, archive management and print function. Results demonstrated that with the powerful data process ability of PC, the system could improve the performance of the traditional ultrasound instrument in detecting cardiac reserve, which provide a powerful support for the further study.

Wavelet transform is internationally recognized a good tool for time-frequency analysis. This paper presents a novel speckle suppression method for medical B-Scan images. The speckle is produced by scattering echoed signals in different phases because of wave interference. The software MATLAB is used as operating platform meanwhile the wavelet is used to eliminate the noise. The ultrasound image is processed by adaptive method and then the selected sym8 wavelet is used in the multiresolution analysis of the ultrasound image. The result shows that this method can effectively reduce the speckle noise.

Bluetooth is a new widely accepted standard of short distance communication in personal area networks (PANs). By analyzing the communication process based on Bluetooth protocol and requirements of physiological electrical signal transmission, such operations are performed as the design of Bluetooth model for measurement of heart sound, the development of Bluetooth network communication library and the implementation of the model by programming.

The general theories of gray correction methods for the medical ultrasonic image are introduced in this paper, including gray level correction, gray level transformation and histogram correction. The dominant histogram equalization method is expatiated and modified against its disadvantages including inapparent enhancement of partial detail and non-interactivity. Series connections of several gray correction methods are used to treat with the ultrasonic image, and thus its utility is improved through the selective enhancement of the contrast of certain gray scope.

This paper analyses the requirements of serial data communication interface between upper and lower hosts in a heart sound sampling system, and then introduces the system design scheme, schematic of hardware interface and source codes of upper and lower hosts. C8051F000 and personal computer adopted as the lower host and upper host respectively, C++ Builder and Windows API functions are also used to implement the applications.

This paper introduces several methods to measure cardiac function, including methods of FICK oxygen consumption, thermodilution, ultrasound cardiography, impedance cardiogram and the method with heart sound. Advantages and disadvantages of each method are discussed and compared. It is suggested that futural cardiac function evaluation approach be highly accurate or simply, noninvasive to meet different application requirements.

Objective To investigate cardiac reserve function and pregnant results of preeclampsia.Methods Pregnant women chosen by randomized table and hospitalized in the department of obstetrics of the first affiliated hospital of Chongqing MedicaI University were involved in this study from January to December,2008.Sixty-nine cases of normal pregnant women were divided into 3 groups:normal group 1(20cases),normal group 2(26 cases)and normal group 3(23 cases).The normal group number 1 to number 3 were paired to gestational hypertension(20 cases),mild preeclampsia(26 cases)and severe preeclampsia (23 cases),respectively.The digital technique of heart sound signal processing WaS used to measure cardiac reserve function parameters including the heart rate(HR),the ratio of the amplitude of the first heart sound to the second heart sound(S1/S2)and the ratio of diastolic to systolic duration(D/S)of pregnant women.The pregnant results were also recorded.Results (1)The ratio of S1/S2 in the group of severe preeclampsia 4.5±3.2 was significantly bigher than the group of gestational hypertension 2.2±1.1 and normal group 32.2±1.1(P＜0.01).The ratio of D/S of the group of severe preeclampsia 1.1±0.3 Was significantly lower than the group of gestational hypertension 1.4±0.3 and normal group 31.4±0.2(P＜0.01).(2)All cases of the normal group number 1 to number 3 and the group of gestational hypertension were found the ratio of D/S≥1.00,whereas 1 case(1/26,4%)of the group of mild preeclampsia and 4 cases(4/23.17%)of the group of severe preeclampsia were found the ratio of D/S＜1.00.(3)The two cases of the pregnant wornen(including one woman died of cardiac arrest)with S1/S2＞5.00 and D/S＜1.00,who were in the group of severe preeclampsia,were sent to Intensive Care Unit after delivery.There were 4 cases(4/26,15%)and 6 cages(6/23,26%)of 1 minute Apgar score less than 7,7 cases(7/26,27%)and 6 cases(6/23,26%)sent to neonatal Intensive Care Unit,2 cases(2/26,8%)and 4 cases(4/23,17%)of neonatal death in the group of mild preeclampsia and in the group of severe preeclampsia,respectively.All newborns in the normal group number 1 to number 3 and the group of gestational hypertension were normal.Conclusions The cardiac reserve function of a pregnant woman with preeelampsia is decreased with the severity of preeclampsia and the parturient and neonatal results get worse.The distal technique of heart sound signal processing is a safe,harmless,simple and effective tool to measure cardiac reserve funotion of preeclampsia,and is worthy of widely used clinically.

The database design of multi-focal visual electric-physiological examining system is introduced in this paper.Microsoft Access 97 is used to design the database.VC++ can append,query or delete records of the database through DAO interface.It reflects such advantages that the database is easy to be managed and convenient to be queried.The design pattern can be transplanted to other medical devices' design.

Heart sounds teletransmission is very important in telemedicine.The heart sounds are transmitted to the server which has been accessed to internet in custody center based on GPRS,then doctors analyze the heart sounds and transmit the conclusion to the consumer.