The Analysis Of The Influencing Factors Of Coronary Collateral Circulation In Patients With Acute Coronary Syndrome

Background：In coronary artery disease patients with severe coronary artery stenosis,the formation of coronary collateral circulation (CCC) can reduce major adversecardiovascular events, improve the function of the heart and prognosis of the patients. Thedevelopment of CCC is influenced by many factors. Among the influencing factors, theclassic ones are researched more, such as diabetes, hypertension, smoking, gender and soon. There are still many arguments but no clear conclusion. In recent years, someresearches indicate that serum uric acid and mean platelet volume (MPV) have closerelationship with formation of CCC in patients with acute coronary syndrome, which areless reported in the domestic and overseas and are not clear. Therefore, we wanted to get amore particular knowledge of the influencing factors of CCC in the patients with severecoronary artery stenosis and acute coronary syndrome by this research, and to explain theirrelationship.Objective: This research discussed the influencing factors of CCC in the patients withsevere coronary artery stenosis and acute coronary syndrome by analysising the clinicaldata and features of coronary angiography，and this research tried to provide its possiblemechanism.Method:1. We studied315consecutive patients who admitted to the First AffiliatedHospital of Soochow University with acute coronary syndrome from March2010to June2013. Totally315patients with at least the stenosis of one vessel≥90％among three mainvessels of coronary artery were enrolled in the study according to angiographic estimation.Development of CCC was classified by Rentrop method. According to the collateral degree, the patients were divided into two groups: non-CCC formation group,191patients withCCC grade0; CCC formation group,124patients with CCC grade1-3. There were42patients with CCC grade1,57patients with CCC grade2,25patients with CCC grade3.2. The retrospective study was to collect clinical data of enrolled patients, such as age,gender, history of diabetes, history of hyperlipidaemia, history of smoking, creatinine, uricacid, MPV and so on. At the same time, features of coronary angiography were collected,such as the locations of coronary artery lesions, severity of coronary artery lesions. Firstly,we assessed the relationship between the formation of CCC and influencing factors bymeans of univariate analysis. Secondly, we used logistic regression analysis to assess theinfluencing factors of statistical significance.3. According to the collateral degree, we divided MPV into four teams. Then weanalyzed the relation between the collateral degree and MPV by spearman correlationanalysis. The patients were also divided into two groups: group of poorly developed CCC,233patients with CCC grade0-1; group of well-developed CCC,82patients with CCCgrade2-3. Then we evaluated the relation between MPV and the development of CCC.Results:1.315patients were enrolled, including CCC formation group (CCC grade1-3) and non-CCC formation group (CCC grade0). After univariate analysis of clinicaldata, age, age of≥65years, history of angina≥3months, history of diabetes, history ofsmoking, uric acid, creatinine and MPV were associated with formation of CCCsignificantly. After univariate analysis of features of coronary angiography, the totalocclusion of coronary artery and three-vessel disease promoted formation of CCCsignificantly.2.Among315patients, there were433main coronary arteries with the stenosisof≥90％.They were191left anterior descending arteries (LAD),102left circumflexarteries (LCX),140right coronary arteries(RCA). The formation of CCC was related to theanatomic location of the lesion: the significantly highest CCC forming rate was found inRCA, the lowest in LCX and the middle in LAD. The compasion of CCC forming ratebetween LAD and LCX was not significant. The proximal lesion can not promote the formation of CCC.3.After multivariate logistic regression analysis of age, age of≥65years, history ofangina≥3months, history of diabetes, history of smoking, uric acid, creatinine,MPV, thetotal occlusion of coronary artery and three-vessel disease, the total occlusion of coronaryartery, three-vessel disease, history of angina≥3months and MPV were independentinfluencing factors of CCC formation.4. According to the collateral degree, MPV levels were divided into four teams.MPVlevels were positively correlated with CCC grade（r=0.133，P=0.018）. The315patientswere divided into two groups: group of poorly developed CCC (CCC grade0-1); group ofwell-developed CCC (CCC grade2-3). Increased MPV promoted the development of CCCsignificantly.Conclusion:1.The total occlusion of coronary artery, three-vessel disease, history ofangina≥3months and MPV were independent influencing factors of CCC formation in thepatients with severe coronary artery stenosis and acute coronary syndrome.2.Among the patients with severe coronary artery stenosis and acute coronarysyndrome, increased MPV promoted the development of CCC significantly. and MPVlevels were positively correlated with CCC grade.3. The formation of CCC was related to the anatomic location of the lesion: thesignificantly highest CCC forming rate was found in RCA, the lowest in LCX and themiddle in LAD. The compasion of CCC forming rate between LAD and LCX was notsignificant. The proximal lesion can not promote the formation of CCC.