Electrical Activity Rhythm Of Ventricular Fibrillation And Defibrillation

Over 50 percent of coronary heart disease death is the result of sudden cardiac death (SCD), which is unexpected occur within an hour of the time that symptoms first appear. The clinical epidemiology investigation demonstrates that the incidence of the SCD is increasing during the past 50 years. Ventricular fibrillation (VF) and ventricular tachycardia (VT) are known to be responsible for many SCD. Because the SCD is paroxysmal and very difficult to salve, most of the sufferer will die in a few minutes and bring the fatal losing to the family and society. So, the research about the mechanism and treatment of VT/VF which correlates with SCD closely is become the advanced and hotspot subject. This is also the fortress in cardiac electrophysiology which need to be captured urgently.This research aimed at the situation that the mechanisms of VT/VF are not understood clearly and the treatments of VT/VF are unitary. We hope that our work will promote the prevention and treatment of VT/VF. The thesis includes "The VT/VF epicardial mapping" and "The research of the shock defibrillation methods".The first part of the thesis describes a 64/176-channel epicardial mapping system designed by ourselves. This system has some particular superorities in location diagnosis and mechanism research of complex arrhythmias. The system was used to mapping the animal's ventricular during the fibrillation. The mapping results demonstrate some special electrical activity characteristics of VT/VF.The second part of the thesis is about the study of the shock defibrillation methods. It can be divided to automatic external defibrillator (AED) and low-energy defibrillation.Because of the important effect the AED acted in the CPR chain. Some advanced countries begin to install AED on the public and train the unprofessional operators in order to decrease the mortality of the SCD. This measurement has obtained the obvious effects. But there is a lack of similar step in our country. So these kinds of work have important practical significance.The kernel problem of the shock defibrillation is reducing the defibrillation energy on the base of preserving the successful ratio. The significance of this kinds research is to reduce the harms to the sufferers during the shock. It can also prolong the life of the implantable cardioverter defibrillator (ICD) and decrease the mental burden of the ICD user. We studied the effect of the waveform to the defibrillation results. The study is also validated by the animal trails.