ST-elevation Of Lead AVR Influences On Prognosis In Patients With Acute Coronary Syndrome

Objective: The changes of ST-segment in lead aVR of electrocardiogramcan be used to diagnose or predict a variety of cardiovascular diseases,severity and prognosis of the diseases. Study shows that the ST-segmentchanges in lead aVR of electrocardiogram, especially in the aspects ofidentifying acute coronary syndrome(acute coronary syndrome, ACS), such asLeft main (Left main coronary artery, LMCA) lesions or three vessels lesionsdisease plays an important role, but for the short-term and long-term outcomesof patients with significance has certain dispute. This study evaluate the shortand long term prognosis of patients with ACS by measuring the degree of STsegment elevation in aVR lead of electrocardiogram in patients who haddiagnosed coronary heart disease. And I combine with the results of patients’GRACE risk score on admission and coronary angiography (coronaryarteriongraphy, CAG) and coronary stenting (percutaneous coronaryintervention, PCI), the condition of heart function, analysis of patients withhospital mortality and incidence of cardiovascular events within3years.Methods:1A total of319patients with ACS were enroalled between January2009and December2012, and all the patients owned12-lead electrocardiogramrecording when they were admitted to hospital, excluding disease or ECGperformance, such as left and right bundle branch block, the pre-excitationsyndrome syndrome and ventricular pacing rhythm, ventricular hypertrophy,pericarditis. The selected patients are divided into two groups: ST-segmentelevation in aVR lead and non ST-segment elevation in aVR lead, bymeasuring ST-segment levels in aVR lead.2Review the CAG and PCI procedure and analysis the CAG informationat the same time, in order to make clear the criminals vessel of patients, coronary artery lesions vessels, vascular stenosis and procedure method forlesions.3Refer to patient history and record the patient general condition onadmission, vital signs, medical history, physical examination, risk factors, andbiochemical indexes, ultrasonic cardiogram, cardiac function after admission,and calculate the GRACE risk score when the patients are admitted to hospital,through above corresponding parameters.4Collect cardiovascular events of patients through their medicalinformation and telephone follow-up results: deaths outside the hospita, deathsin three years at discharge, rehospitalization rate, recurrence of myocardialinfarction, heart failure and stroke.5Analysis data, delete the incomplete data, and use SPSS13.0statisticalsoftware for the data analysis. Classification variable data were shown asproportionto, and continuous variable data was shown as mean±standarddeviation. According to comparison between each group, continuous variabledata is applied independent sample t-test, classification variable data is usedchi-square test, and use multiple Logisitc regression analysis and multivariateCox survival analysis, use hypothesis test for the correlation, and describe thepatients’ survival curve with Kaplan-Meier method. The above data teststandards is P <0.05for the test of significance level.Results:1In all the patients with ACS, there are192patients (60%) with ST-elevation in aVR lead,29patients(15%) with medical history of myocardialinfarction,80patients (42%) with history of diabetes,88patients (46%) withsmoking history. However, in the group of patients with non ST-elevation inaVR lead, there are8patients (6%) with history of myocardial infarction,38patients (30%) with history of diabetes,40patients (32%) with smokinghistory, and they all have significant statistical difference after chi-square test.Comparing to patients with non ST-segment elevation in aVR lead, patientswith ST-segment elevation in aVR lead have more history of myocardialinfarction, diabetes and smoking, a higher cardiac function classification and GRACE risk score.2The patients with ST segment elevation in aVR lead, the CAG showedhigher risks of left main lesions or three lesions, criminals’ vessels for LMdisease and cardiovascular mortality rates in hospital were23%and7%respectively. Comparing to the group of patients with non ST-segmentelevation in aVR lead,23patients with culprit vessels of left main lesion (10%,P=0.006),140patients with triple vessel lesions (73%, P=0.001),47patientswith coronary artery bypass treatment (24%, P=0.015) in ST-segmentelevation in aVR lead, significantly higher than the group of patients with nonST-segment elevation in aVR lead. According to the every different grades ofGRACE risk score, the groups of patients with ST-segment elevation in aVRlead have a higher risk of LMCA lesions, and high-risk group of GRACEscore.3In multivariate regression analysis, the ACS patients in hospital withCardiac function Killip≧2levels have the risk of hospital mortality, odds ratio6.128,95%confidence interval [CI] is2.078to18.071, P=0.001, and withcardiac function Killip≧2levelshave the risk of outside hospital death, HRvalue8.630,95%confidence interval [CI]2.101to35.443, P=0.003,comparing to the patients with non ST-segment elevation in aVR lead, the riskof mortality in hospital increases in patients with ST-segment elevation in aVRlead (odds ratio9.032,95%confidence interval (CI)1.158~70.466, P=0.036), the incidence of cardiovascular events outside the hospital alsoincreases (odds ratio7.157,95%confidence interval2.144~18.887, P=0.001). Thus, ST-segment elevation in aVR lead is concerned with the ACSpatients’ increased risk of death in and outside hospital, and has a great valueof predicting for their prognosis.428patients (15%) are died of cardiovascular events in3years follow-up.Depicting two groups of patients survival curve by Kaplan-Meier methods,and discerning the percentage of death in3years with ACS patients from thecurve, the group of patients with ST-segment elevation in aVR lead have ahigh risk of outside hospital death (the Log Rank test P=0.014), especially highest death rate in1year. In multivariate analysis, ST-segment elevation inaVR lead is a strong, independent predictive factor for cardiovascular death.Conclusion:1In patients with ACS, ST-segment elevation in aVR lead, is associatedwith high risk of coronary artery lesions, such as left main lesion, serious threevessels lesions.2In patients with ACS, ST-segment elevation in aVR lead, have a higherGRACE score, and have a higher risk of in-hospital deaths and for3-yearcardiovascular death comparing with non ST-segment elevation in aVR lead.3for the patients who were admitted to hospital with ACS, doelectrocardiogram inspection immediately. According to the condition ofST-segment elevation in aVR lead of patients on admission, it could help toassess risk stratification and take early and effective interventions in patientswith ACS, and thus it can reduce the risk of death in the hospital, and have acertain value for the prognosis of these patients.