System For Detecting And Diagnosis Of The High Frequency Ventricular Reoplarization Waves And Prediction Of Sudden Cardiac Death

Sudden cardiac death is a sudden,rapid and unexpected death due to cardiac causes.It is seriously harm to the human health.Sudden cardiac death has the characteristics of high incidence,incidence of sudden and high mortality.People will die within one hour once they have this symptom.Considering the existing technology level of first aid,a victim's chance of survival will be reduced by 7 to 10 percent with the heart arrest for one more minute.If this time exceeds 10 minutes,the chance of survival will be very little.More unfortunately,there are 60%to 70%of sudden cardiac death occured outside the hospital and in these cases it is impossible for the victims to get a professional salvage within 10 minutes.So the effective way to deal with sudden careiac death is not salvage after the incident but prediction and prevention before.The research for the prediction of sudden cardiac death has gone for decades and the prediction methods which have abroad influence have developed to as many as a dozen.But all these methods have their own limitations and so far there is no methods can perfectly meet the practical clininical needs.This paper is based on the newly discovered high frequency ventricular repolarization waves(HFVRW),a series of high frequency waves existing in the ventricular repolarization section(S-T-U section).Because of the close relationship between sudden cardiac death and ventricular repolarization and the value of high frequency ECG signal for the diagnosis of heart diseases,it can be predicted that the high frequency ventricular repolarization waves will have great potential in the prediction of sudden cardiac death and the diagnosis of heart diseases.The significance of the high frequency ventricular repolarization waves research reflects in several aspects:(1) High frequency ventricular repolarization waves has the potential to get a better result than QT variable and T-wave alternans(TWA) in prediction of sudden cardiac death.(2) The risk of sudden cardiac death can be monitored through HFVRW before,during and after treatment for patients who have heart failure.(3) High frequency ventricular repolarization waves will be a new means for clinical heart disease diagnosis.This project is supported by the National Natural Science Foundation of China (Project No.:60571034).It will provide advanced hardware and software platform for the research of the high frequency ventricular repolarization waves and perform further research on the procreant mechanism of the HFVRW and the relationship between the HFVRW and sudden cardiac death.The main work of this thesis is as follow:(1) Discovered and put forward this brand new electrocardial phenomenon:the high frequency ventricular repolarization waves.A more depth study to the HFVRW will open a new field of research and will provide new methods for the diagnosis of heart diseases and prediction of the risk of SCD.(2) Carried out research on the electrophysiological base of HFVRW from the point of heart electrophysiologyl and heart model structure.Make a preliminary demonstrate tomechanism of HFVRW.All above can provede a theoretical basis and practical reference for the future experiments and vivisection intracardiac mapping.(3) Carried out research on the characteristics and patameters of HFVRW of patients suffered from ventricular tachycardia and myocardial infarction by using clinical trials and ECG database.Valueble finding has been got.The pathological characteristics of HFVRW can demonstrate the potential and research significance of the HFVRW from the aspect of experiment,and can provide a foundation for the establishment of the HFVRW positive diagnositic criteria.(4) Resolved the key problem for the body surface detection of HFVRW.The non-invasive body surface HFVRW detection has been achieved by the combining using of zero phase shift filtering,adaptive filtering and wavelet domain wiener filtering.This method has been used for the non-invasive detection of His bundle waves.Comparison with abroad research in the same period reveals that this method has a certain advance.In addition,this method is not limited to the detection of His bundle waves and HFVRW.It can be applied to the general case of weak signal detection after a certain adjustment.(5) Established the norms of the HFVRW,set up the hardware platform and integrated software system fot the detection and carried out improvement in some aspect of normal ECG processing,such as the QRS peaks detection and ECG compression.This integrated system can provide tools for the research of HFVRW.The work and conclusion of this paper has achieved the expected purpose and reach the requirements of the National Natural Science Foundation of China.