The Clinical Research Of Microvolt T-wave Alternans Detected By Dynamic Electrocardiogram For Patients With Acute Coronary Syndrome

ObjectiveTo investigate the changes of microvolt T-wave alternans (MTWA) and Heart rate variability (HRV) detected by dynamic electrocardiogram in acute coronary syndrome (ACS) patients,for the risk stratification , clinical treatment of sudden death in patients with ACS,Further explore the mechanism of MTWA , the correlation of coronary artery diseased region and the number of coronary artery disease with MTWA changing in ACS.MethodsMTWA test detected by dynamic electrocardiogram with MMA(Modified moving average analysis) was performed in acute coronary syndrome patients (n=66) and Control group (n=27) . All the acute coronary syndrome patients coronary arteriongraphy showed coronary artery stenosis greater than 70%.I group: Acute myocardial infarction(n=38); II group UAgroup(n=28) ; III group Control group(n=27), People with negative coronary angiography.Results1. Acute myocardial infarction(I)group MTWA related parameters were significantly higher than Control(III)group, statistically significant difference (P<0.01 or P<0.05); Unstable angina pectoris(II)group MTWA related parameters were significantly higher than III group, but no statistically difference(P > 0.05);3) Acute myocardial infarction(I)group MTWA related parameters were significantly higher than Unstable angina pectoris(II)group, Max TWA channel1(mV5) and channel3 (mV3)statistically significant difference(P<0.05).2. Acute myocardial infarction(I)group divided into single coronary artery disease(Ia), double coronary artery disease(Ib), three coronary artery disease(Ic), Control( III) groups Compared the MTWA each other.1) Ia,Ib, Ic group MTWA related parameters were significantly higher than III group, except channel2(mV1) of Ic the other statistically significant difference(P<0.01 or P<0.05);2) Ia,Ib group MTWA related parameters were significantly higher than Ic group, statistically significant difference(P<0.01 or P<0.05);3)Ia vs Ib groups MTWA related parameters showed were significantly higher than Ib ,only channel2(mV1) statistically significant difference (P<0.05).3. Unstable angina pectoris (II)group divided into single coronary artery disease(IIa), double coronary artery disease(IIb) and three coronary artery disease(IIc), IIa,IIb, IIc and Control( III) groups Compared the MTWA each other.1) IIa,IIb group MTWA related parameters were significantly higher than III group, except channel1(mV5) and channel3(mV3) of IIb the other statistically significant difference(P<0.01 or P<0.05);2) IIc group MTWA related parameters were significantly lower than III group, but no statistically difference(P>0.05);3)IIa vs IIb groups MTWA related parameters showed were significantly higher than IIb , but no statistically difference(P>0.05).4. Acute myocardial infarction group , 1)channel1(mV5) with left circumflex branch, right coronary artery and, the number of coronary artery disease have midrange negative correlation;2) channel3(mV3) with right coronary artery and, the number of coronary artery disease have midrange negative correlation, channel3(mV3) with left circumflex branch negative correlation but P>0.05; 3) channel2(mV1) with right coronary artery, left circumflex branch and the number of coronary artery disease have negative correlation but p>0.05;3) three channel with anterior descending branch, C-reactive protein and left ejection fraction have positive correlation but P>0.05.5. Unstable angina pectoris 1)channel1(mV5) with right coronary artery, blood pressure and the number of coronary artery disease have midrange negative correlation, with left circumflex branch have negative correlation but p>0.05;2) channel3(mV3) with left circumflex branch, blood pressure and the number of coronary artery disease have midrange negative correlation, with right coronary artery hve negative correlation but p>0.05; 3) channel2(mV1) with right coronary artery, left circumflex branch, blood pressure and the number of coronary artery disease have negative correlation but p>0.05;3) three channel with anterior descending branch have positive correlation but p>0.05.Conclusion1) MTWA can be used as reference for risk stratification; 2) three channel microvolt T-wave alternans influenced by the number of coronary artery disease and region of coronary artery, Max TWA with right coronary artery, left circumflex branch and the number of coronary artery disease have negative correlation, with anterior descending branch have positive correlation, single coronary artery diseasea, have larger TWA than double coronary artery disease and three coronary artery disease.