Analysis On The Clinical Features Of Coronary Collateral Vessel Development In Patients With Coronary Artery Disease

ObjectiveTo investigate the factors which influence the development of coronary collateral circulation(CCC) as well as the effect of CCC on QT dispersion, heart rate turbulence(HRT), left ventricular ejection fraction(LVEF), brain natriuretic peptide (BNP) by analyzing the medical records of the patients with coronary artery disease.MethodsRetrospectively analyzed 115 patients with coronary artery disease (CAD) confirmed by coronary angiography between January 2009 and December 2010.The patients were categorized into three groups according to the Werner's classification which were CC0(n=69), CC1(n=30), CC2(n=16). Grading of collateral filling was as follows: CC grade 0 =no continuous connection, CC grade 1=thread like continuous connection, CC grade 2=side branch-like connection. The severity of coronary artery disease is determined by Gensini Scoring System. The retrospective study was to analysis the relationship between coronary collateral circulation (CCC) and factors such as clinical characteristics, angiographic characteristics of patients by means of univariate analysis and logistic regression analysis. Results(1) Clinical features: Among CC2,CC1,CC0 group there were not significantly differences in age and gender .(2) Angiographic characteristics: 1) The severity of stenosis in coronary artery determined by Gensini Scoring System in CC2 group,CC1 group were significantly higher than in CC0 group(93.63±21.82 vs 75.79±28.29 vs 57.21±25.05, P=0.000);CC2 group were also significantly higher than in CC1 group. 2) The total occlusion of lesions vascular in the both CC2 group and CC1 group was higher than CC0 group(93.7% vs 83.3% vs 30.0% , P=0.000), there were not significantly differences among 3 groups in the subtotal occlusion(99.0%stenosis) and in the number of stenosed vessels . These data suggested that the severity of stenosis in coronary artery was positively correlated with the development of CCC. There was no relation between the number of lesion vascular and collateral circulation. 3) Angiographically detectable collaterals were present in 50 of 62 totally occluded arteries and in 13 of 28 arteries with sub-totally occlusion (99.0%stenosis). These data indicated that collateral circulation in patients with CAD cannot be seen angiographically unless there is total or sub-total occlusion.(3) Past medical history: There were not significantly differences in hypertension (62.3% vs 63.5% vs 68.7%), diabetes mellitus (23.2% vs 30.0% vs 25.0%) among CC0,CC1,CC2 groups.(4) Univariate analysis revealed there was negative correlation between the serum level of hs-CRP and CCC development.(5) Electrocardiogram: 1) QT dispersion, Corrected QT interval dispersion increased significantly in CC0 group than in CC1 group (228.86±158.39 vs 121.10±152.08; 214.12±154.81 vs 110.60±143.3). CC0 group also prolonged compared with CC2 group, but the difference between CC0 group and CC2 group were not significantly (228.86±158.39 vs 187.37±147.43; 214.12±154.81 vs 179.62±149.74). The results suggested that the impact of coronary stenosis on QT dispersion weakened the impact of CCC on QT dispersion. 2) There was not significantly difference in heart rate turbulence (turbulence onset, turbulence slope) among three groups.(6) There were not significantly differences in the serum level of BNP (130.88±204.54 vs 215.11±281.79 vs 138.19±124.6) and in left ventricular ejection fraction (LVEF) among CC2,CC1,CC0 group (55.89±7.27 vs 55.04±9.05 vs 55.0±7.36).(7) Multinomial logistic analysis revealed that the severity of coronary artery disease determined by Gensini Scoring System and the percentage of total occlusion were the factors which influence the development of coronary collateral circulation with the regression coefficient statistically significantly different (P<0.05).Conclusion(1) The degree of vessel occlusion is the most important factor which influence the development of coronary collateral circulation. (2) There was no relation between the number of lesion vascular and collateral circulation. (3) Collateral circulation in patients with CAD cannot be seen angiographically unless there is total or sub-total occlusion. (4) Coronary collateral circulation can limit myocardial ischemia and reduce the alterations in the electrophysiological characteristic of myocardial cells.