冠状动脉旁路移植术血管桥痉挛处理进展

随着冠状动脉搭桥手术 (CABG)趋于成熟 ,内乳动脉 (IMA)、桡动脉 (RA)、大隐静脉 (SV)等血管桥广泛采用 ,取材过程中 ,压力扩张、溶液冲洗、血管桥营养血管破坏等均能引起内皮细胞损伤。血管内皮细胞释放内皮源性一氧化氮 (NO)、前列环素 (PGI2 )、内皮依赖性超级化因子 (EDHF)等血管活性物质参与内皮增生、炎症反应、免疫调节及血管平滑肌张力调节。内皮功能不全或内皮细胞损伤引起NO、PGI2、EDHF生成及释放减少 ,术中及术后血管桥痉挛经常发生 ,从而引起心肌血流量减少 ,血栓形成 ,降低血管桥近期及远期通畅率。因而 ,深入理…     

血管内皮源性超极化因子的功能以及在肺移植外科的临床意义

血管内皮细胞通过由血管内皮细胞所释放的一些特殊的、能使血管达到舒张的舒张因子来调节血管局部的血液动力学状态。这些舒张因子是一氧化氮 (NO) ,前列环素 (PGI2 )以及内皮源性超极化因子 (EDHF)。尽管EDHF的作用已在多种动脉血管中被证实 ,但其确切的化学本质并未完全明了。高钾溶液可减少其EDHF介导的舒张功能。本文综述了有关EDHF的作用、功能以及与肺移植外科领域相关的资料。     

血管内皮源性超极化因子的功能以及在肺移植外科的临床意义

血管内皮细胞通过由血管内皮细胞所释放的一些特殊的、能使血管达到舒张的舒张因子来调节血管局部的血液动力学状态。这些舒张因子是一氧化氮(NO)，前列环素(PGI2)以及内皮源性超极化因子(EDHF)。尽管EDHF的作用已在多种动脉血管中被证实，但其确切的化学本质并未完全明了。高钾溶液可减少其EDHF介导的舒张功能。本文综述了有关EDHF的作用、功能以及与肺移植外科领域相关的资料。     

冠状动脉搭桥材料的内皮细胞分泌的一氧化氮和内皮素水平研究

目的检测冠状动脉搭桥患者桡动脉和大隐静脉内皮细胞所分泌的一氧化氮(NO)和内皮素(ET)水平,并与脐静脉内皮细胞相比较,了解内皮细胞的功能。方法利用剩余的冠状动脉搭桥移植材料,采用Ⅱ型胶原酶消化的方法获取内皮细胞并培养,收集培养细胞的上清液,利用试剂盒检测内皮细胞分泌的NO和ET水平。结果与人正常脐静脉内皮细胞相比,冠状动脉搭桥材料桡动脉和大隐静脉内皮细胞分泌的NO水平显著降低(P<0.05),ET水平显著增高(P<0.05)。结论冠状动脉搭桥患者桡动脉和大隐静脉的内皮细胞与脐静脉内皮细胞相比,所分泌的NO和ET差异有统计学意义,冠状动脉搭桥患者搭桥材料的内皮细胞分泌功能可能存在功能障碍。     

微生物感染与冠状动脉桥血管的选择

目的　探讨微生物感染对冠状动脉桥血管的可能影响。方法　用聚合酶链反应方法检测大隐静脉、内乳动脉、桡动脉组织中肺炎衣原体、幽门螺杆菌和巨细胞病毒。结果　大隐静脉存在血管硬化病理改变为 6 9.6 % ,内乳动脉为 6 5 .0 % ,桡动脉为 73.3% ,差异无显著性 (χ2 =0 .397,P =0 .82 )。肺炎衣原体、幽门螺杆菌和巨细胞病毒的阳性率在大隐静脉分别为 13.0 %、8.7%和 0 .0 % ,内乳动脉分别为 2 5 .0 %、35 .0 %和 0 .0 % ,桡动脉分别为2 6 .7%、2 3.3%和 16 .7%。桡动脉肺炎衣原体、幽门螺杆菌和巨细胞病毒的阳性率高于大隐静脉 ,χ2 分别为 1.4 6、2 .797和 4 .2 33(P <0 .0 5 ) ;内乳动脉肺炎衣原体、幽门螺杆菌和巨细胞病毒的阳性率与大隐静脉相比 ,χ2 分别为1.0 10、4 .4 73和 0 .0 0 0 ,内乳动脉幽门螺杆菌的阳性率高于大隐静脉 (P <0 .0 5 )。结论　慢性微生物感染影响最小的是大隐静脉 ,其次为内乳动脉和桡动脉     

冠状动脉旁路手术中动脉材料的选择与应用

目的 在冠状动脉旁路手术(CABG)中寻求动脉材料作旁路移植，减少因大隐静脉桥(SVG)阻塞对远期通畅率的影响。方法 34例冠心病患者以乳内动脉(IMA)和桡动脉(RA)作为血管桥行CABG，采用不接触血管技术制备动脉桥，应用药物防止动脉痉挛。结果 取乳内动脉35根，桡动脉20根，大隐静脉11根，平均移植血管1．94支，死亡1例，手术死亡率2．9％。结论 使用动脉材料行旁路移植术安全有效，预计能保持移植血管长期通畅。     

中国常用动脉化冠状动脉旁路移植术的通畅率及疗效

目前冠状动脉旁路移植术通常采用一支乳内动脉加一支或多支大隐静脉作为桥血管,大隐静脉会逐渐粥样硬化而闭塞,动脉的通畅率远高于大隐静脉。左乳内动脉已常规应用于冠状动脉旁路移植术,同应用双侧乳内动脉相比,左乳内动脉加大隐静脉被认为是远期死亡、心脏事件的独立危险因素。乳内动脉用于左侧冠状动脉时通畅率一样;原位或复合桥移植时所有的乳内动脉通畅率相同,但吻合于主动脉时通畅率降低,所以原位乳内动脉通畅率高于游离乳内动脉。胃网膜右动脉和桡动脉宜吻合于近端狭窄严重者。双侧乳内动脉+胃网膜右动脉可避免触及主动脉,最大程度地减少脑部并发症的发生。70岁以下冠状动脉旁路移植术、预期寿命5年以上者,应选择双侧乳内动脉;60岁以下没有或很少合并症的冠状动脉旁路移植术患者可考虑全动脉化搭桥手术。     

冠脉旁路血管桥痉挛的防治研究

大隐静脉、乳内动脉、桡动脉、胃网膜右动脉等是冠脉搭桥术最为常用的血管桥材料,它们生物学特性不同,各自的生理和病理特点也不一样,发生血管痉挛的机制和防治方法也不尽相同.针对不同的血管桥,采取积极的抗痉挛策略,是提高冠脉搭桥手术效果的重要环节.     

冠脉旁路血管桥痉挛的防治研究

大隐静脉、乳内动脉、桡动脉、胃网膜右动脉等是冠脉搭桥术最为常用的血管桥材料，它们生物学特性不同，各自的生理和病理特点也不一样，发生血管痉挛的机制和治疗方法也不尽相同。针对不同的血管桥，采取积极的抗痉挛策略，是提高冠脉搭桥手术效果的重要环节。     

大隐静脉和上臂头静脉移植对70岁以上病人心肌血管重建作用的比较

目的　冠状动脉旁路移植术是治疗缺血性心脏病一种常规方法 ,但是由于所采用的移植血管不同 ,导致治疗的效果也不尽相同。目前治疗常用的血管为大隐静脉 +乳内动脉为标准手术术式。然而诸多原因限制 ,有时大隐静脉不适合作为移植材料。本研究对大隐静脉与上臂头静脉作为移植材料进行比较。方法　接受乳内动脉和大隐静脉旁路移植术组 35例 ,平均年龄 77岁 ,接受乳内动脉 +上臂头静脉旁路移植术组 15例 ,平均年龄 75岁 ,二组之间 ,体重 ,心肌梗死病史 ,心功能 ,平均每例冠状动脉病变以及平均移植血管数没有明显差别。结果　乳内动脉和大隐静脉旁路移植术组和乳内动脉 +上臂头静脉旁路移植术组之间 ,乳内动脉的五年累计通畅率分别为 96 %和94 % ,二组之间没有显著性差异 (P>0 .0 5 ) ,大隐静脉的通畅率为 70 % ,上臂头静脉为 4 8% ,二组之间差异性不明显 (P>0 .0 5 )。结论　通过两组间的 5年累计通畅率的比较 ,我们认为在高龄病人上臂头静脉作为移植血管效果差 ,术后通畅率低 ,但可以作为移植血管的最后选择。     

Comparison of the Effects of Levosimendan and Papaverine on Human Internal Mammary Artery and Saphenous Vein

Purpose  

Internal mammary artery (IMA) and saphenous vein (SV) are two most common vessels used in coronary artery bypass grafting (CABG). In the present study, the effect of levosimendan (a novel inotropic/vasodilator compound) and papaverine are compared, using IMA and SV obtained from CABG patients.     

Native matrix metalloproteinase characteristics may influence early stenosis of venous versus arterial coronary artery bypass grafting conduits

PURPOSE: Stenosis and occlusion rates of internal mammary artery (IMA) and saphenous vein (SV) coronary artery bypass grafts (CABGs) are markedly different, which result from respective disparities in vascular remodeling. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) regulate vascular structure and may have important influence on graft patency. However, the MMP milieu and expression profile of the IMA and SV have not been contrasted. Therefore, the aim of this study was to assess and compare the native MMP systems in IMA vs SV conduits. METHODS: IMA (n = 10) and SV (n = 10) specimens were obtained from patients undergoing CABG surgery. Protein levels of MMP-1, MMP-2, and MMP-9, TIMP-1, a membrane-bound MMP activator (MT1-MMP), and an extracellular MMP inducer protein (EMMPRIN) were determined by immunoblotting and quantified by densitometric analysis. MMP-2 and MMP-9 activity was determined by gelatin zymography. RESULTS: MMP-2 levels were significantly higher in SV (2,218 +/- 351 pixels) vs IMA (1,012 +/- 213 pixels) specimens (mean +/- SEM]). There were no significant differences in MMP-1, MMP-9, or TIMP-1 content; however, MT1-MMP and EMMPRIN levels were significantly lower in SV (847 +/- 190 pixels, 1,742 +/- 461 pixels) vs IMA conduits (2,590 + 403 pixels, 5,606 + 678 pixels), respectively (p < 0.05). MMP-9 activity was similar while MMP-2 activity was significantly increased in SV vs IMA specimens. CONCLUSIONS: SV and IMA conduits harbor the same MMP molecular constituents. However, MMP-2 levels and activity are significantly more abundant in the SV compared to the IMA. These differences may contribute to the early pathologic remodeling of the SV vs IMA conduit following CABG surgery.     

桡动脉、乳内动脉、大隐静脉中RhoA/ROK mRNA 的表达与心血管危险因素的相关性

目的 探讨桡动脉（RA）、乳内动脉(IMA)、大隐静脉(GSV) 中RhoA/Rho 激酶（ROK）mRNA表达的差异，以及心血管危险因素对其表达的影响。方法 取14例CABG术中废弃的配对RA、IMA、GSV各5～10 mm，用RT-PCR检测RhoA/ROK mRNA的水平。采用多元逐步回归分析心血管危险因素对3种桥血管中RhoA/ROK表达的影响。结果 ①RT-PCR:IMA与GSV比较，RhoA和ROK mRNA表达的水平无显著差异；但RA中RhoA 和ROK mRNA表达的水平显著高于IMA（P<0.01，P<0.05）。②多元逐步回归分析显示，GSV中RhoA和ROK mRNA表达的水平与糖化血红蛋白呈显著正相关（r=0.642、r=0.692,P<0.05）。3种血管中RhoA、ROK mRNA的表达与年龄、总胆固醇、三酰甘油、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、载脂蛋白A1、载脂蛋白B、C反应蛋白、胰岛素、胰岛素抵抗及体质量指数均无显著相关。结论 ①RA、IMA、GSV管壁中RhoA/ROK mRNA的表达有差异，RA中Rho/ROK mRNA的表达明显强于IMA。②糖化血红蛋白可影响GSV 中RhoA/ROK mRNA的表达。     

Contractile properties of coronary artery bypass conduit--comparison between saphenous vein and internal mammary artery

This study was designed to examine the response of coronary artery bypass conduit to serotonin, phenylephrine, and ergonovine as provocation agents of vasoconstriction. Saphenous veins (SV) and internal mammary arteries (IMA) were obtained during coronary artery bypass grafting (CABG), and their contractile properties were measured using isometric contraction recording apparatus. Both SV and IMA showed sigmoid contraction curves indicating dose dependence to ergonovine, serotonin, and phenylephrine. The concentration-response relations for phenylephrine showed a similar curve in both SV and IMA, however, those for ergonovine and serotonin showed a leftward shift in SV compared with IMA. Half maximum effective dose for ergonovine and serotonin were less in SV than IMA. From these results, it was suggested that "perioperative spasm" during CABG might occur not only in coronary arteries but also in the graft conduit itself. Graft spasm might be a possible mechanism for occlusion of the bypass graft. In conclusion, greater hyperreactivity of SV compared with IMA in response to ergonovine and serotonin was suggested, so it is concluded that, from this point of view, IMA is more suitable for use in CABG.     

Strategy for post coronary artery bypass grafting in patients with bypass graft stenosis: comparison of percutaneous transluminal coronary angioplasty for the native coronary artery, internal mammary artery and saphenous vein graft]

OBJECTIVES: The strategy for post coronary artery bypass grafting (CABG) was investigated in patients with graft stenosis. METHODS: The study included 123 post-CABG patients with graft stenosis. The patients were divided into three groups according to target vessels; saphenous vein graft (SVG; n = 72), internal mammary artery (IMA; n = 21) and native coronary artery (n = 30). Furthermore, SVG lesions were divided into proximal anastomosis (n = 23), body (n = 40) and distal anastomosis (n = 9). The procedural success rate and late patency rate were compared between the three groups. Furthermore, the relationships between pre percutaneous transluminal coronary angioplasty (PTCA) percentage diameter stenosis, procedural success rate and late patency rate were evaluated. RESULTS: Procedural success rate was similar in the three groups, but late patency rate was higher in the IMA group. Procedural success rate and late patency rate were significantly lower in proximal anastomoses compared to other sites of SVG stenoses, IMA group and native coronary artery group (p < 0.05). Totally occluded native coronary artery lesions had a high procedural success rate compared with occluded IMA and SVG lesions, but the late patency rate was not higher. Procedural success rate showed no significant difference for 75-99% stenotic lesions, but the late patency rate was significantly higher in the IMA group (p < 0.05). Patients in the stenting group had a greater late patency rate compared with the balloon angioplasty group. There was no significant difference in late patency rate between the IMA group and SVG group. CONCLUSIONS: Late patency rate of the IMA is higher than that of the native coronary artery. SVG with proximal anastomosis and severe stenosis shows a significantly lower late patency rate than the native coronary artery. Therefore, PTCA should be considered for the native coronary artery in the absence of chronic total occlusion.     

Influence of colforsin daropate hydrochloride on internal mammary artery grafts.

The effect of colforsin daropate hydrochloride (colforsin), a water-soluble forskolin derivative, on blood flow in internal mammary artery (IMA) grafts was evaluated in a prospective randomized study of 26 patients undergoing coronary artery bypass grafting. Patients were randomized to receive either colforsin treatment (colforsin; n=14) or no colforsin treatment (control; n=14). Administration of colforsin (0.5mg x kg(-1) min(-1)) was started after induction of anesthesia and was continued for 6 h. IMA blood flow and hemodynamic measurements were assessed perioperatively. During cardiopoulmonary bypass (CPB), perfusion flow was adjusted to 2.5 L/m2 and IMA free blood flow was measured. IMA blood flow was also measured 1 h after CPB by an ultrasonic flow meter. Systemic vascular resistance was significantly lower in the colforsin group during and after CPB. IMA blood flow was significantly greater in the colforsin group than in the control group during (44 +/- 2 vs 33 +/- 3 ml min-1 x m(-2), p=0.02) and after CPB (38 +/- 6 vs 20 +/- 3ml x min(-1) m(-2), p=0.01). IMA blood flow 1 h after CPB correlated inversely with concurrent systemic vascular resistance (r=-0.61, p=0.001). Intraoperative administration of colforsin daropate hydrochloride caused potent vasodilation, resulting in an increase in IMA blood flow. The results indicate that the regimen can be used perioperatively in patients undergoing coronary artery bypass grafting.     

全动脉化冠状动脉旁路移植74例

目的:介绍全动脉化冠状动脉旁路移植（CABG）的早期效果和经验。方法:74例全动脉化CABG的患者。74例患者分别在体外循环（CPB）和非CPB下行CABG。应用左乳内动脉（IMA）1例,左IMA加单挠动脉（RA）14例,左IMA加双RA 54例,双IMA加双RA 3例,双RA 2例。人均搭桥4.7（17）支,序贯吻合66例,“Y”和“T”型吻合分别为15和6例。结果:围手术期无死亡。本组患者随访518（平均12.2）个月,均恢复良好,无心绞痛症状再发。多普勒和16排CT示血管桥无狭窄通畅。结论:全动脉化CABG取得好的早期效果,是一种值得积极推广的方法。     

Triple arterial coronary revascularization using the radial artery and bilateral internal mammary arteries versus the gastroepiploic artery and bilateral internal mammary arteries.

Arterial grafts are frequently used in modern coronary artery bypass grafting (CABG) and the benefit of the 2 internal mammary arteries (IMA) has already been established. However, the choice of the third arterial conduit, in addition to the IMA, is controversial. We have retrospectively analized perioperative and the follow-up results of patients who underwent CABG with triple arterial bypass using either the radial artery (RA) or the gastroepiploic artery (GEA) in conjunction with the bilateral IMA (BIMA). Between December 1995 and June 2001, 1,516 consecutive isolated CABG operations were performed at Shin-Tokyo Hospital. Among them the RA and BIMA were used in 96 patients (78 males, 18 females; mean age, 63.2+/-6.7 years, group R), and the GEA and BIMA in 123 patients (101 males, 22 females; mean age, 61.0+/-11.6 years, group G). Their perioperative and follow-up data were studied. The preoperative risk factors were similar between the 2 groups, except that there were significantly fewer patients with renal dysfunction in group R. The surgical results did not differ between the 2 groups; however, the GEA was more commonly used for revascularization of the right coronary artery, while the RA was used for the diagonal, circumflex or right coronary arteries. Surgical mortality and morbidity rates were not significantly different. During the follow-up period of 2.3+/-1.6 years, the event-free rates as well as the survival rates were not significantly different. CABG with either the RA or the GEA in conjunction with the BIMA can be performed safely. The surgical results as well as the follow-up results were acceptable and no significant differences between the 2 groups were observed.     

Effect of sternotomy and coronary bypass surgery on postoperative pulmonary mechanics. Comparison of internal mammary and saphenous vein bypass grafts

Coronary artery bypass grafting (CABG) is commonly performed via a median sternotomy with a reversed saphenous vein (SV) and/or an internal mammary artery (IMA) graft. Sternotomy and IMA harvesting may adversely affect postoperative respiratory function (PFTs) as disruption of the sternun may impair chest wall stability, and the decrease in intercostal muscle blood supply after removal of the IMA may reduce the force of respiration. We compared preoperative and six- to eight-week postoperative PFTs in patients undergoing CABG. The results were independent of age, sex, number of grafts, aortic cross clamp time, duration of bypass run, and postbypass fluid gradient. It was concluded that sternotomy caused a decrease in postoperative PFTs and that IMA harvesting may be accompanied by greater impairment in PFTs than when SV grafts alone were used.     

Nitric Oxide Modulation of Neutrophil-Endothelium Interaction: Difference Between Arterial and Venous Coronary Bypass Grafts

Objectives. This study sought to evaluate the relation between the pattern of neutrophil-endothelial adhesion in saphenous vein (SV) and internal mammary artery (IMA) grafts and the endothelial production of nitric oxide (NO).Background. Autologous IMA and SV grafts (SVGs) are increasingly used as conduits for coronary bypass grafting. Previous studies have demonstrated a greater production of endothelial-derived relaxing factor (NO) from IMA than from SVGs. Because of the well known role of NO in modulating the adhesion of polymorphonuclear leukocytes to the endothelium, we studied the pattern of neutrophil adhesion to the endothelium of IMA and SVs under basal conditions and after inhibition of NO synthesis.Methods. Segments of IMA and SVs were obtained from 20 patients undergoing coronary artery bypass graft surgery. We evaluated the adhesion of both unstimulated and activated neutrophils to the endothelial surface of IMA and SVs in both basal conditions and after inhibition of NO synthesis with N^ω-nitro-l-arginine methyl ester.Results. Under basal conditions, no difference in unstimulated neutrophil adhesion to endothelium was observed between the two vessel conduits. After neutrophil activation, a significantly (p < 0.05) greater adhesion of neutrophils was observed in the SV than in the IMA. After inhibition of NO release, the adhesion of activated neutrophils increased in both vessels, and no significant difference between them was observed. The increased adhesion was attenuated by both l-arginine and sodium nitroprusside.Conclusions. The lesser neutrophil adhesion to the endothelium of the IMA is a consequence of enhanced release of NO at this level; this effect could be responsible for the better early and long-term patency of this conduit over the SVG in coronary bypass grafting.