冠状动脉旁路移植术患者桡动脉的病理改变及其危险因素分析

目的 了解冠状动脉旁路移植术（CABG）患者桡动脉的内膜增生程度和动脉粥样硬化发生率,分析相关危险因素。方法对41例采用桡动脉行CABG（17～70岁,平均48．5岁,均为男性）患者的非优势侧桡动脉的远端组织,及其中11例患者的左乳内动脉的远端组织,采用光镜结合电镜观察内膜增生、动脉粥样硬化和中层钙化的发生率,测量管腔狭窄度和内／中膜面积值,分析与家族史、吸烟、超重、高血压、高血脂、糖尿病以及年龄、冠状动脉造影病变情况的相关性。结果93％（38／41）的桡动脉内膜增生轻,不构成有临床意义的狭窄,其中54％（22／41）的桡动脉管腔狭窄度低于25％,39％（16／41）狭窄在25％～50％之间;7％（3／41）狭窄超过75％（梗阻性内膜增生）,其中2例为动脉粥样硬化斑块,1例为纤维肌性结构不良（17岁,手术获取后放弃）。桡动脉的管腔狭窄度和内／中膜面积值,高于同体的左乳内动脉（t=3．00,2．49,P均〈0．05）,且随年龄的增加而增厚（r=0．398,0．310,P均〈0．05）。动脉中层未见光镜水平的钙化。结论本组患者桡动脉内膜增生较轻,无中层钙化;少数内膜梗阻性病例术前可能漏诊,应提高术前筛查水平。

Pathological changes of radial artery used for coronary artery bypass grafting and its related risk factors for intimal hyperplasia

Objective To examine the degree of intimal hyperplasia and the prevalence of atherosclerosis in radial arteries taken from the patients undergoing coronary artery bypass grafting(CABG),and to analyze the risk factors to obtain some helpful information for choosing arterial conduits. Methods Forty-one radial arteries and 11 internal mammary arteries samples were collected.The average age of patients was 48.5 years,and they all were male.Intimal hyperplasia,atherosclerosis,medial calcification were evaluated by routine histological methods,and the severity of diseases was measured on the percentage of luminal narrowing and the intima-to-media ratio(the intima area/media area).The risk factors for coronary heart disease were also analyzed. Results Ninety-three percent(38 of 41) of radial arteries showed mild intimal hyperplasia,which was not regarded to influence blood flowing after CABG.As a part of them,54%(22/41) of radial arteries had a lower than 25% of luminal narrowing,meanwhile 39%(16/41) of radial arteries had the percentage of luminal narrowing between 25% and 50%.Only 7%(3 of 41) of radial arteries were found to have occlusive lesions,which made arterial lumen decreased more than 75%.The 3 patients including 2 with severe atherosclerosis and another 1 aged 17 years was involved by fibromuscular dysplasia.The later vessel was discarded after harvesting.The percentage of luminal narrowing and the intima-to-media ratio were higher in radial artery than that in internal mammary artery(t=3.00,2.49,P<0.05).The two parameters were positively correlated with age(r=0.398,0.310,P<0.05),but this study failed to show any relationship between intimal hyperplasia of radial artery and coronary lesions and other risk factors.Medial calcification was not found by routine histological method in all cases. Conclusion Only mild intimal hyperplasia and no medial calcification are found in radial arteries used for CABG in the patients.Because the risk factors could not yet predict the severity of radial arterial lesions,this study strongly suggestes that the Doppler ultrasonography and pre-operation clinical consideration should be emphasized to screen out some arteries with occlusive lesions.