Direct revascularization of the myocardium using the internal mammary artery

The best graft in coronary bypass operations is the internal mammary artery (IMA) as its rate of staying open for long term is better than that of the vena saphena magna. The authors present the operative and postoperative results of their first 161 patients who were subjected to IMA grafting. 126 were men and 35 women of the patients and the average age was 50.2 years. Before the operation the majority of the patients belonged to NYHA III state (69.6%). 86 patients (53.4%) had myocardial infarction before the operation, 50.3% were operated on because of 3 blood vessel diseases and the stricture of the main trunk was confirmed in 12.4%. 128 patients underwent only coronary bypass operation, in the others thrombendarterectomy (17 patients), valvular operation (11 patients) and resection of the left ventricular aneurysma (5) were carried out simultaneously. The IMA graft was placed in the majority of the cases on the LAD (70.8%) or as a sequential anastomosis on the LAD-diagonal system (21.1%). The average number of peripheral anastomoses was 2.8 anastomoses patient. 2.5% was the rate of early mortality (4 patients), reoperation was performed in 10 cases because of bleeding or tamponade and perioperative infarction occurred in 8 cases. 3.1% was the rate of late mortality (5 patients). The average follow-up examination time was 12.7 months (3-39 months). At the postoperative examinations 88.8% of the patients were free of angina and 108 patients got into NYHA I state after the operation. Of the 43 control bicycle ergometric examinations 35 were negative and 8 positive.(ABSTRACT TRUNCATED AT 250 WORDS)     

内乳动脉和桡动脉的临床解剖与组织学研究

目的　研究冠状动脉旁路移植术 (CABG)动脉血管材料———内乳动脉 (IMA)、桡动脉 (RA)的临床解剖和组织学特征。方法　采用游标卡尺分别测量CABG患者术中IMA、RA长度及近远端外径各 30例 ;光学显微镜下观察CABG术中收集到的IMA、RA远端片段各 30根。并测量IMA、RA内、中膜各层厚度。采用动脉内膜与中膜厚度之比判断动脉硬化程度并将其分为 0级、Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级。结果　测量IMA平均长度 18.2 5cm(16 .10～ 2 0 .4 0cm) ,外径近端和远端分别为 3.10mm(2 .99～ 3.2 1mm)和 2 .0 3mm(1.90～ 2 .16mm) ;RA平均长度 2 2 .0 6cm(19.5 6～2 2 .5 6cm) ,外径近端和远端分别为 3.2 1mm(3.0 9～ 3.33mm)和 2 .6 0mm(2 .5 0～ 2 .70mm)。IMA与RA之间比较无显著性差异 (P >0 .0 5 )。IMA和RA内、中、外膜三层结构清晰 ,两者的显微结构很为相似。IMA与RA动脉硬化程度之比P >0 .0 5。结论　IMA和RA有足够的长度能满足CABG ,IMA和RA直径与冠状动脉相匹配。IMA和RA均为搏动性的肌性动脉血管 ,解剖与组织学比较相差无显著性。均为较理想的动脉移植材料。     

超声刀在骨骼化乳内动脉采取中的应用

目的总结超声刀在骨骼化乳内动脉血管桥采取中的使用经验。方法回顾性分析日本顺天堂大学医院60例接受了超声刀采取的双侧乳内动脉血管桥进行单纯冠状动脉旁路移植术冠心病患者的临床资料及随访资料。结果远端吻合口平均（4．1±1．5）个。术后并发严重心律失常2例，脑梗塞合并败血症、弥漫性血管内凝血合并多脏器功能衰竭各1例，肺部感染2例，手术死亡2例。术后随访（15．6±3．2）个月，远期无死亡或心脏性事件患者。结论超声刀的应用使乳内动脉的骨骼化采取变得安全、简单。骨骼化双侧乳内动脉在冠状动脉旁路移植中具有良好的早期效果。     

CT血管造影在冠状动脉旁路移植术前对乳内动脉评价的价值

目的:探讨CT血管造影在冠状动脉旁路移植术前对乳内动脉评价的价值,旨在为临床提供安全可靠的检查方法。方法:将34例冠状动脉旁路移植术前患者的CTA的原始数据传至后处理工作站进行图像的重建。采用原始轴位图像与重建图像相结合的方式进行综合分析评价,测量并记录乳内动脉的起源、走行规律、近段有无大分支,与胸骨的距离、全程长度、直径及横截面积,左右乳内动脉各指标间的差异采用独立样本均数比较的t检验。结果:34例移植前患者的乳内动脉(IMA)均可清晰的显示,5例患者的IMA起源异常,1例患者双侧IMA纤细,2例患者左侧IMA较右侧明显纤细,同时发现4例左侧锁骨下动脉(SCA)近段狭窄。IMA左右各参数之间比较无显著性差异(P>0.05)。结论:在乳内动脉-冠状动脉搭桥术前,CT血管成像检查是评价乳内动脉安全可靠的方法。     

Analysis of the stable metabolite of endothelium-derived nitric oxide of internal mammary artery bypass grafts at the venous drainage system of the recipient coronary artery. Morphologic implications and consequences

INTRODUCTION: The internal mammary artery's endothelium continuously produces nitric oxide in a large quantity resulting in local and downstream vasodilatation, inhibition of platelet aggregation and in the tunica media prevents smooth muscle cell proliferation. OBJECTIVE: The aim of this study was to measure the concentration of the internal mammary artery bypass graft's endothelium derived nitric oxide's stable metabolite, (nitrite) at the venous drainage site (great cardiac vein) of the recipient coronary artery (left anterior descending), and to prove that the change of the biochemical milieu provides morphological stability (vasodilation and lack of atherosclerosis) in the recipient coronary artery based on recoronarographies. METHOD: Authors investigated the levels of endothelium derived nitric oxide in intraoperative settings of 50 off pump, partly heparinized coronary bypass surgery cases sampling from the internal mammary free cut end flow (81.2 +/- 12.1 mumol/l), the great cardiac vein (anterior interventricular vein) prior and after arterial bypass graft completion and in the systemic circulation (42.9 +/- 7.1 mumol/l), The stable metabolite concentration measurement was carried out with the modified Takafumi Ohta method utilizing fluoroscopy. Out of the 200 samples 164 were feasible to analyze. RESULTS: A significant increase was found in the great cardiac vein, comparing concentrations measured prior and after IMA anastomosis completion: 46.7 +/- 11.4 mumol/l, and 71.12 +/- 13.1 mumol/l, respectively (p < 0.05). CONCLUSION: Based on these findings, due to the continuous protective (vasodilatative and antiatherogen) effect of the IMA provided EDNO, the recipient artery shows no pathological changes in time. This was proved by studying recoronarographies of 103 patients--with prior coronary bypass surgery in 5-12 years using the IMA, and with new symptomatology. Out of 87 functioning IMA to LAD grafts, 85 LAD showed no atherosclerotic changes, while in the same patients' other coronary systems significant, de novo stenotic lesions had developed.     

MR imaging of internal carotid artery occlusion

Five patients with internal carotid artery occlusion were studied with MR imaging at 0.22 T. At the carotid siphon, occluded vessels showed absence of flow void in three patients. But two cases had "partial flow void" which mimicked small arterial caliber. In these patients angiography showed collateral circulation to the carotid siphon. So the partial flow void in the carotid siphon suggested internal carotid artery occlusion with collateral circulation.     

Alteration of nitric oxide production during arterial myocardial revascularization using extracorporeal circulation. Quantitative measurement of EDNO production by the internal mammary artery bypass graft

Authors measured the concentration of stable metabolite (NO2: nitrite) of EDNO (endothelium derived nitric oxide) in the internal mammary artery (IMA) bypass graft with the help of a previously reported method (measurement of effective blood flow capacity of the IMA graft in the coronary sinus). Nitrite level in the systemic circulation prior to extracorporeal circulation (ECC)--(68.1 +/- 6.7 mumol/l) was measured, as well as nitrite concentration in the coronary circulation before and after construction of the IMA bypass graft (62.1 +/- 4.19 mumol/l and 50.26 +/- 4.0 mumol/l respectively). Furthermore, nitrite level in the IMA graft free cut end flow was also determined (64.3 +/- 5.9 mumol/l). These data compared to the nitrite levels in the normal plasma (48.1 +/- 5.9 mumol/l) were found to be higher (p = 0.1, ns.), possibly due to the enhanced EDNO production induced by total heparinization. The nitrite concentration in the IMA free cut end flow is similar or slightly higher than that of the native coronary circulation, however, after IMA bypass construction a relative reduction could be measured in the coronary sinus. Authors believe, that this may be related to the reduction of basal EDNO production caused by supernormal pO2 (215 +/- 19 mmHg) during ECC.