Effect Of Diabetes Mellitus On The Formation Of Coronary Collateral Circulation

First partAimsTo investigate which clinical factor can affect development of coronary artery collateral circulationMethodsPatients underwent coronary angiography in2010at Huashan hospital, who showed at least one of their main coronary artery branch stenosis up to90%was enrolled in this study, meanwhile who have a history of coronary artery bypass surgery were excluded. All patients were divided into diabetic and no-diabetic group according to if they are suffering diabetes. Clinic base line character and biochemical indexes were assessed in both groups respectively. Patients also were divided into two groups according to their collateral circulation developing condition. Clinic character and biochemical indexes also be assessed in this two groups.When investigate the relationship between the collateral circulation development and clinic character, the condition of age, gender, smoking history, alcohol consuming, obesity, hypertension, blood lipids, renal function, cardiac function and coronary artery stenosis time should be calibrated, so we established the Logistic regression model to conduct multivariate analysis.Results1. Compare the clinic character between the two groups:collateral circulation developed and no-collateral circulation developed.Collateral circulation development is highly related to degree and course of stenosis. In our dates, significant correlation between the diabetes and collateral vessel forming was not observed (p=0.094). It is possible that the interference factors were not completely calibrated.2. Compare the clinic indexes between diabetic and no-diabetic group.Compare to the no-diabetic patients, the diabetic patients have more serious degree of coronary artery stenosis. The results have significant statistical difference (p=0.0001). Evaluated by3kinds of scoring method, we found that diabetic patient acquire higher scores than no-diabetic patient (p=0.046、0.049、0.045respectively). In addition, there is higher ratio female patient in diabetic group.3. For excluding interference factors and obtaining more accurate results, binary logistic regression was conducted.To explore the relation between diabetes and collateral circulation development, calibrate potential interference factor, independent variable was conducted as this: collateral circulation development was identified as dependent variable, age, gender, smoking history, alcohol consuming, obesity, hypertension, percentage of non-HDL(non-high density lipoprotein cholesterol), GFR(glomerular filtration rate),Pro-BNP, LVEF(left ventricular ejection fraction), severity of stenosis, duration of stenosis, diabetes, insulin resistance index were identified as independent variable. Selection of these factors is according to previous laboratory and clinic works. Results showed that diabetes (P=0.047, OR=2.049), lesion vessel number (P=0.035, OR=1.547), duration of stenosis (P=0.012、OR=1.412) were positive correlation with collateral circulation formation while age (P=0.005, OR=0.184) negative correlation with circulation formation.Conclusion1.The severity and duration of stenosis is determinants of coronary artery collateral circulation forming. More serious and long period of stenosis more easily induce the development of collateral vessel, so higher collateral hemodynamics scores.2. Diabetes improves the coronary collateral circulation developing, diabetic patient more apt to develop collateral circulation.3. There are correlation between age and coronary collateral circulation development; older people are scored lower than younger people.Second partAimsWe evaluated the coronary collateral circulation of the patient who suffered serious coronary artery stenosis or occlusion by manifold evaluation method. Further explore the role of diabetes played in collateral circulation development and function.MethodsAssessing of collateral circulation adopted widely-used Rentrop score, along with other two kinds of scoring method (collateral flow score, receiving flow score) When assessing the relation between the collateral circulation and clinic character, these factors should be calibrated:age, gender, smoking history, hypertension history, blood lipids, renal function, blood flow velocity in culprit vessel, period of coronary artery stenosis and cardiac function. In this study, we use the ordinal logistic regression model. When identify the correlation between the variable and collateral circulation, P<0.05regard as statistical significance.Results1. Spearman correlation coefficient test were conducted between two of the three methods (Rentrop score, collateral flow score, receiving flow score). The values of correlation coefficient among them all less than0.09, p value less than0.01. These results indicated that it is highly correlative and coherence among these three methods. It won’t induce significant deviation when use then to assess collateral flow.2.Secondary grouping the enrolled patient according to the grade of collateral flow score, re-assessment of clinic character of these groups and conducting bivariate Sperman correlation coefficient test. Diabetes (P=), lesion vessel number (P=), multi-vessel lesion, sub-total occlusion and total occlusion vessel number (P=), duration of stenosis (P=) are positive correlation with collateral flow scores.3.To calibrate the interference factor, ordinal Logistic regression analysis was conducted.Rentrop scores as dependent variable, gender, smoking history, alcohol consuming, obesity, hypertension, percentage of non-HDL(non-high density lipoprotein cholesterol), GFR(glomerular filtration rate),Pro-BNP, LVEF(left ventricular ejection fraction), severity of stenosis, duration of stenosis, diabetes, insulin resistance index were identified as independent variable, ordinal Logistic regression analysis was conducted. Diabetes (P=0.036, correlation coefficient0.775), severity of coronary artery stenosis(P1=0.047, correlation coefficient1=0.756; P2=0.034, correlation coefficient2=0.014), duration of stenosis (P1=0.025, correlation coefficient0.876; P2=0.027, correlation coefficient2=0.462; P3=0.038, correlation coefficient3=0.381) are positive correlative with collateral flow. Age (P=0.019, correlation coefficient=-1.348).4.Explore the relationship among diabetes, severity of coronary artery stenosis and collateral circulation. In the above-mentioned model, removing the variable of lesion vessel number, conduct the ordinal Logistic regression analysis again. In this condition, p value is0.009, correlation coefficient increase to0.908, bigger than previous one. Comparing the p value and correlation coefficient of other variables, no significant change was observed, this suggest that diabetes affect collateral circulation development mainly through inducing coronary artery stenosis. Compared to the effect on coronary artery stenosis, diabetes have very weak influence on collateral circulation.5.1dentifying Rentrop score and receiving flow score as dependent variable respectively, conduct similar ordinal Logistic regression analysis acquire similar results.Conclusion1, Diabetes improves the coronary collateral circulation developing, diabetic patient more apt to develop collateral circulation.2. There are correlation between age and coronary collateral circulation development; older people are scored lower than younger people.