Application Of Signal Averaged Method To Discuss The Value Of Repolarization Alternans In Treadmill Exercise Testing And The Diagnosis Of Myocardial Ischemia

Objective:Application of signal averaged method to detect Repolarization alternans, To discuss the value of Repolarization alternans in diagnosing CHD by its changes in patients of the CAG negative and positive during treadmi ll exercise testing.Methods:Retrospective analysis on 192 cases which using Bruce method to check the patients,s restrictive symptom in TET, these patients are suspected of having C HD w hich fo und in C AG exa mination in hal fyear. Ap plication o f signal superposition method to all patients in the process of movement with RA test analysis,To measure RA values X+uαs about the negative groups as the RA test positive judgment standard,The RA measurement values of each lead ≥X+uαs as positive,The RA measurement values of each lead <X+uαs as negative. Observing the timing of various parameters change with STSA and TWA relations, thesepatients have been divided into two groups“negative and positive”according t o C A G r e s u l t s. T h e r e a r e 9 5 C A G p a t i e n t s w i t h p o s i t i v e w h o s e y e a r s o l d(58.23±10.42)and 97 patients with negative, years old 54.45±9.66.Comparing different groups of patients’ s T wave alternans and the relations to severity of coronary arterial atherosclerosis,CAG positive groups has been divided into Sv D, Dv D and Mv D.To analysis T wave alternans complex and the relation to lesion location of coronary artery, Sv D group has been divided into four subgroups: A(LAD), B(LCx), C(RCA) and D(LM).Results:The TWA variation in RA are very obvious after exercise,the incidence of RA in chest lead change is large,limb lead change smaller, STSA values change is not significantly as TWA value.The incidence of TWA in CAG positive group was higher than that negative groupafter movement,there were significant differences inlead V4 before movement.Theincidence rate of TWA lead in chest V2、V4、V5 、V6 about CAG positive group increased after movement, there was significant differences between two groups(P < 0.05);The incidence rate of STSA before and after movement were not significant differences between groups and within groups(P > 0.05).After movement,the incidence rate of TWA in CAG negative group and Sv D group lead in chest V2、V4、V5 、V6, and Dv D group lead in chest V2、V3、V4, and Mv D group lead in chest V2、V4,were significant differences(P < 0.05);Yet the comparison between Sv D group and Dv D group, Sv D group and Mv Dgroup,Dv D group and Mv D group, degree of the lesion in these parameters were undifferentiated(P>0.05).After movement,the incidence rate of TWA in CAG negative group and LAD group lead in chest V2、V4、V5、V6, and LCX group lead in chest V2, and RCA group lead in chest V2、V3、V4,were significant differences(P < 0.05).Yet the comparison between LAD group and LCX group, LAD group and RCA groups, LCX group and RCA group, diseased region in these parameters are undifferentiated(P>0.05).Conclusion:1.The TWA variation are very obvious about RA after exercise,the incidence of RA in chest lead change is large, limb lead change smaller, STSA values change is not significantly as TWA value.2.The incidence rate of TWA lead in chest V2、V4、V5 、V6 about CAG positive group increased after movement, there was significant differences between two groups.3.The incidence of TWA in CAG positive group was higher than that in negative group after movement.4.The incidence rate of TWA was not involved in coronary artery diseased region anddegree of the lesion.5.Application of signal superposition ECG method can be used as an effective method of repolarization alternans.