CT血管造影分析体外循环与非体外循环冠状动脉旁路移植后的桥血管通畅率

背景：近年来,非体外循环冠状动脉旁路移植后桥血管通畅率是否与传统的体外循环冠状动脉旁路移植相同存在争议。 目的：探讨体外循环与非体外循环冠状动脉旁路移植后桥血管时间通畅率的差异性。 方法：选取同一操作者行体外循环冠状动脉旁路移植患者100例,按其临床特征及桥血管病变危险因素匹配抽取非体外循环冠状动脉旁路移植患者137例。采用64排多螺旋CT血管造影分析冠脉搭桥后1个月,1年,2年,3年,4年的桥血管通畅情况。 结果与结论：共对641条桥血管进行评价,两组中左侧乳内动脉桥血管时间通畅率均高于大隐静脉桥,两组左侧乳内动脉桥和大隐静脉桥血管时间通畅率比较差异均无显著性意义。说明非体外循环与体外循环冠状动脉旁路移植后患者桥血管时间通畅率相似,对于某些适当的患者来说,非体外循环冠状动脉旁路移植不失为一个良好的选择。     

The impact of the preoperative severity of target-vessel stenosis on the short-term patency of radial artery grafts

The fate of a grafted radial artery remains unknown. The purpose of this study was to determine whether the preoperative severity of stenosis of the target vessel influence short-term patency of radial artery (RA) grafts used as coronary artery bypass conduits. In 54 patients who had coronary artery bypass grafting (CABG) with RA grafts, RA patency was determined with multi-slice computed tomography (MSCT) 1 year after CABG. These patients were divided into three groups on the basis of the percentage of the target vessel stenosis: mild (< 60%, n=17), moderate (60% to 79%, n=19), and severe (>/= 80%, n=18). MSCT was also performed 1 week later to exclude early occlusion of RA grafts. In 3 patients, the MSCT failed to adequately discriminate the status of the RA graft due to poor image resolution. The overall incidence of RA occlusion was 23.5% (12 of 51) at 1 year in the entire population. The mild stenosis, moderate stenosis and severe stenosis group showed an occlusion rate of 50% (8 of 16), 23.5% (4 of 17) and 0% (0 of 18), respectively. The severe stenosis group had significantly lower rate of RA graft occlusion compared to the mild stenosis group (p < 0.001) and moderate stenosis group (p < 0.05). No difference in occlusion between grafts used for the different coronary artery branches could be demonstrated. Preoperative severity of the target coronary artery significantly affected the short-term RA grafts patency. Correct indication is the key factor for short-term RA patency.     

Uterine artery as an arterial conduit for coronary artery bypass graft (CABG) surgery in women: A role for estrogen-receptor alpha (ER-α) in the prevention of post-CABG accelerated atherosclerosis and graft disease

Coronary artery bypass graft (CABG) surgery is the standard of care in the treatment of advanced coronary artery disease (CAD). In order to bypass coronary occlusions, CABG surgery traditionally employs grafts from the left internal thoracic/mammary artery (LITA/IMA), radial artery (RA), and greater saphenous vein (SV). The risk of CABG failure is reported to be higher, or at best similar, for women than for men, and it relates primarily to post-operative accelerated atherosclerosis leading to graft stenosis and recurrent angina, a phenomenon known as “coronary artery bypass graft disease”. In this paper, the authors hypothesize that employing an alternative arterial conduit may help reduce the rate of post-CABG accelerated atherosclerosis in women, and propose that a uterine artery specimen be used instead. Given its greater density of estrogen-receptor alpha (ER-α) relative to other mammalian endothelial cells in the vasculature, uterine arteries may exhibit important anti-atherosclerotic properties. Theoretically, this effect may be amplified with the adjuvant administration of low-dose selective ER-α agonist modulator (SERM) therapy.     

Endothelial hypoxia induction of atherosclerosis: an explanation of patency rates for internal mammary artery and other coronary artery bypass grafts

The major etiological factors of atherosclerosis are reviewed and the case strengthened for endothelial hypoxia being the major initiator. Hypoxia is also shown to be the major cause of coronary artery bypass graft occlusions. The pathophysiological differences between pedicle and free arterial grafts and venous grafts are discussed. Arguments are presented to explain why pedicle internal mammary artery grafts have longer lasting a patency then saphenous vein grafts. It is proposed that free grafts using other systemic arteries should also give very acceptable results and may, in certain circumstances, be desirable over pedicle internal mammary artery grafts. The differences between single, Y and sequential grafts are also discussed to explain differences in patency rates.     

冠状动脉旁路移植术所用桡动脉与乳内动脉的超微结构比较

目的 桡动脉与乳内动脉的生物学特性及冠状动脉旁路移植术后的远期通畅率不同,本研究拟了解桡动脉与乳内动脉的超微结构差异及其对移植术后血管重构的可能影响。方法 在冠状动脉旁路移植术中采集桡动脉远端34例及乳内动脉远端11例。用电镜观察、比较两种动脉的内皮细胞及其脱落比例、内膜平滑肌细胞表型、基质分泌量、内中膜脂质和中层亚显微钙化的有无、中层平滑肌细胞的超微形态和排列。结果 桡动脉内膜较厚,内膜平滑肌细胞较多而密集。它在分泌态内皮细胞（47．1％,16／34）、合成型平滑肌细胞比例（14．4％）、内膜脂质（内膜44．1％,15／34;中膜58．8％,20／34）和基质分泌量增加（14．7％,5／34）方面高于乳内动脉（分别为27．2％,3／11;0．9％;内膜18．2％,2／11及中膜54．5％,6／11;9．1％,1／11）。动脉中膜可出现较多基质小泡及其钙化,而光镜水平未发现钙化,姑且称之为亚显微钙化。桡动脉的中层脂质和亚显微钙化与乳内动脉持平,内皮细胞的肿胀脱落却少于乳内动脉。两者的中层平滑肌细胞结构和排列未见显著差异。结论 冠心病患者桡动脉内皮细胞功能状态和内膜平滑肌细胞潜在的增殖能力高于乳内动脉,它可能参与移植术后重构,并与其远期通畅率较低有关。桡动脉获取中内皮保护较乳内动脉好,有利于通畅率的提高。     

Difference between endothelium-dependent relaxation in arterial and in venous coronary bypass grafts

Both the internal mammary artery and the saphenous vein are used to construct coronary-artery bypass grafts. We hypothesized that the release or production of endothelium-derived relaxing factor, which regulates blood flow and inhibits platelet function, may differ in venous and arterial grafts. We therefore studied endothelium-dependent relaxation in internal mammary arteries, internal mammary veins, and saphenous veins obtained from 58 patients undergoing coronary bypass surgery. Vascular rings with and without endothelium were suspended in organ chambers, and isometric tension was recorded. Acetylcholine (10(-8) to 10(-4) M), thrombin (1 U per milliliter), and adenosine diphosphate (10(-7) to 10(-4) M) evoked potent endothelium-dependent relaxation in the mammary artery but weak response in the saphenous vein (P less than 0.005; n = 6 to 27). In the mammary artery, relaxation was greatest in response to acetylcholine (86 +/- 4 percent reduction in norepinephrine-induced tension), followed by thrombin (44 +/- 7 percent) and adenosine diphosphate (39 +/- 8 percent). In the saphenous and mammary veins, relaxation was less than 25 percent. Relaxation was unaffected by indomethacin but was inhibited by methylene blue and hemoglobin (P less than 0.005 and 0.01, respectively), which suggests that endothelium-derived relaxing factor was the mediator. Endothelium-independent relaxation in response to sodium nitroprusside was similar in arteries and veins. We conclude that endothelium-dependent relaxation is greater in the mammary artery than in the saphenous vein. The possibility that this contributes to the higher patency rate among arterial grafts than among venous grafts will require further study.     

Biometry and structure of the left internal thoracic and radial coronary arteries

In an attempt to elucidate the causes of occlusion of radial arteries for coronary artery bypass grafts, we studied the biometry and histology of the coronary, radial and left internal thoracic arteries of 20 anatomical subjects (13 males and 7 females). These specimens were calibrated to the various bypass graft sites using coronary calibrators, and were then submitted to histological examination to determine the structure of the vessel wall. Our preliminary results show no correlation between the internal calibres of these various arteries. Like the coronary arteries and their branches, the radial artery is a muscular artery. In contrast, the left internal thoracic artery like the aorta, is an elastic artery.     

Histologic study of coronary, radial, ulnar, epigastric and internal thoracic arteries: application to coronary artery bypass grafts

The biometry and the histology of coronary, radial, ulnar, epigastric and internal thoracic arteries were studied in order to investigate the cause of their occlusions in coronary bypass grafts and to improve the results of these bypass grafts. These various arteries were removed from 40 anatomical specimens (27 males and 13 females). We found a correlation between the internal calibers of the ulnar and coronary arteries in males. Intimal changes and the presence of atheromatous plaque were observed in coronary, radial and ulnar arteries, but never in the internal thoracic artery. Like coronary arteries and their branches, radial, ulnar and epigastric arteries are muscular arteries and ageing results in thickening of the intima, which becomes fibrotic with migration of myocytes from the media and duplication of the internal elastic lamina. The media becomes fibrous, hypertrophic or atrophic. In contrast, the internal thoracic artery is an elastic artery, like the aorta. Ageing is characterized by loss, over a variable extent, of one or several elastic laminae of the media and more marked intimal thickening. Although anatomically, the caliber of radial, ulnar, and epigastric arteries remains adapted to that of coronary arteries, the long-term patency of radial, ulnar and epigastric arteries used as grafts is related to their histological characteristics.     

Elective vs non-elective radial artery grafts: comparing midterm results through 64-Slice computed tomography

BACKGROUND: Left internal thoracic artery to left anterior descending artery (LITA-LADA) grafting has become a fundamental part of the coronary artery bypass graft procedure (CABG). This grafting in turn has led to an increased use of other arterial conduits, of which the radial artery (RA) is most popular. Whether RA grafting can be used in the emergency patient is controversial. METHODS: 47 patients with critical stenosis (>70%) in all target vessels underwent CABG with LITA and RA grafts from 1996 to 2003. Patients were divided into elective (23 patients) and non-elective groups (24 patients) with LITA and RA grafts per patient being similar in both groups. Of these 47 patients, 5 died from non-cardiac complications and 12 were unavailable. Thus, 30 patients (71% of survivors) were studied by multidetector computed tomography. A total of 36 LITA and 64 RA grafts were studied. RESULTS: The RA patency rate for elective and non-elective grafts were 82% (31/38) and 85% (22/26), respectively (p=0.75). The RA had a similar patency rate for all target vessels ranging from 73% to 100%. Only one patient had a redo CABG and 29 (97%) are free from angina or re-intervention. LITA-LADA had a 92% (11/12) and 100% (10/10) patency rate for elective and non-elective groups, respectively (p=0.37). The sequential LITA-diagonal-LADA in the elective group had a 50% (03/06) patency rate, which was significantly lower than the 100% (08/08) patency rate of the non-elective group (p=0.02). CONCLUSION: Radial Artery grafts can be used in both elective and non-elective patients with excellent results.     

桡动脉提取在高流量脑血管搭桥手术中的应用

目的　探讨桡动脉提取技术在高流量脑血管搭桥中的应用。 方法　回顾性纳入2015年1月至2021年6月天津市环湖医院32例以桡动脉为桥血管行高流量脑血管搭桥手术患者,统计桡动脉所取长度及内径、收缩期峰值流速、舒张末期流速、内膜厚度、阻力系数等相关参数,应用影像学及临床数据评估手术效果,术后桥血管通畅率及并发症等有效性、安全性指标。 结果　本组患者无围手术期死亡,32例患者共搭桥32根,所取桡动脉平均长度（20.20±2.06）cm,近心端内径平均（2.41±0.28）mm,远心端内径平均（2.28±0.42）mm,各项参数及Allen's试验、造影等检查提示所取桡动脉通畅性良好,满足高流量搭桥需要,本研究中提取桡动脉搭桥技术成功率100%,术后随访影像学检查示搭桥通畅,患者均未出现因桥血管痉挛而导致的缺血性卒中,前臂及腕关节肌力较术前未下降,4例患者出现前臂外侧皮神经及桡神经浅支损伤症状并于3月内缓解。 结论　提取桡动脉技术应用于脑血管搭桥具有安全性、有效性,该技术配合高流量脑血管搭桥术在颅底肿瘤、复杂脑血管疾病等领域具有广阔的应用前景。     

Thallium scintigraphy in prediction of occlusion of bypass grafts in asymptomatic and symptomatic patients

To evaluate thallium scintigraphy in predicting coronary artery bypass graft patency, exercise thallium scintigraphy and selective graft and native vessel angiograms were performed in 22 asymptomatic and 29 symptomatic consecutive patients three months after coronary artery bypass grafting (CABG). Twelve out of 22 asymptomatic patients (55%) had reversible thallium defects on postoperative images; in 10 patients the postoperative scans were normal. The graft patency was significantly lower in asymptomatic patients with abnormal thallium perfusion compared to those with normal perfusion after CABG (68% vs. 91%, p less than 0.05). The rate of graft patency in symptomatic patients was 66/87 (76%). Thallium scintigraphy was 77% sensitive and 78% specific in detecting one or more stenosed or occluded bypass grafts in patients without angina (accuracy 77%). When data from exercise electrocardiography were combined with scintigraphy, all but one patient with incomplete revascularization could be detected (positive predictive accuracy 92%). In symptomatic patients, thallium scintigraphy accurately predicted the presence or absence of graft occlusion in 24/29 (83%) cases. Thus, abnormal myocardial perfusion due to stenosis or occlusion of bypass grafts is common in both asymptomatic and symptomatic patients after CABG. Thallium scintigraphy together with exercise electrocardiography appear to be useful non-invasive methods in detecting painless myocardial ischemia and in predicting bypass graft occlusion after CABG.     

Atrial fibrillation as a contributing factor in the diagnostic algorithm for coronary subclavian steal syndrome and cardiac tamponade following coronary artery bypass graft surgery: a case study

Coronary subclavian steal syndrome (CSSS) is a complication of coronary artery bypass graft (CABG) surgery in patients with coexistent significant subclavian artery stenosis (SAS). It is characterized by a retrograde blood flow through the left internal mammary artery graft from the coronary to subclavian circulation, leading to myocardial ischemia. Current screening for CSSS includes bilateral blood pressure measurement for the detection of a significant inter-arm blood pressure difference. However, the commonly used automated sphygmomanometers have limited accuracy in patients with atrial fibrillation. Consequently, these patients are often underdiagnosed. We present a case of a 73-year-old man with a medical history of atrial fibrillation, peripheral artery disease, and CABG surgery four months before the current event, who came to the emergency department due to progressive dyspnea. The initial diagnostic management showed a large circulatory pericardial effusion, so the patient was admitted to the coronary care unit and underwent pericardial drainage. In the following days, due to a sudden high increase in cardiac troponin, the patient underwent an urgent coronary angiography, which revealed severe left SAS with functional CABG, indicating the occurrence of CSSS. Percutaneous transluminal angioplasty was then performed with an optimal angiographic result. The patient was discharged in good condition with adequate medicament therapy and instructions. This case report highlights atrial fibrillation as a contributing factor for the diagnosis of CSSS and pericardial tamponade after CABG surgery. Furthermore, we suggest a diagnostic approach that can reduce the incidence of both these severe complications.

Coronary subclavian steal syndrome (CSSS) occurs in the presence of subclavian artery stenosis (SAS) or occlusion and represents a reversal of blood flow in the left internal mammary artery (LIMA) bypass graft, which leads to coronary ischemia. It presents as a complication in 2.5–4.5% of patients undergoing coronary artery bypass graft (CABG) surgery. The prevalence is even higher in patients with peripheral artery disease (PAD), who have a 5-fold increased risk of SAS (1,2). It commonly presents as stable angina triggered by left upper extremity activity, but can also manifest as an acute coronary syndrome, acute heart failure, ventricular arrhythmia, or even sudden cardiac death (3). Digital subtraction angiography, the current gold standard in the imaging of CSSS, has lately been increasingly replaced by other diagnostic tools, such as duplex ultrasound (DUS), computed tomography angiography (CTA), and magnetic resonance angiography. The current guidelines recommend the endovascular approach as the first-line treatment of CSSS and vascular surgery as the second option (4).     

多普勒超声在全动脉化冠状动脉旁路移植术前桥血管筛查中的应用价值

目的:探讨多普勒超声在全动脉化冠状动脉旁路移植(CABG)术前评估桡动脉及左侧乳内动脉的临床应用价值。方法:回顾性研究。纳入2018年1月—2020年1月蚌埠医学院第一附属医院收治的60例冠心病患者,其中男34例、女26例,年龄44～76岁。患者术前均使用多普勒超声检查左侧乳内动脉及双侧桡动脉。(1)分别采用超声和Al...     

冠状动脉旁路移植术后静脉桥再狭窄的基因治疗研究进展

冠状动脉旁路移植术是治疗缺血性心脏病安全、有效的方法.自体大隐静脉是术中最常用的移植血管材料.但是血栓形成、内膜增厚和粥样硬化导致的静脉桥再狭窄严重影响了其通畅率,而且至今尚无有效的治疗药物.分子生物学技术理论的发展为冠状动脉旁路移植术后静脉桥再狭窄的防治提供了新思路,基因治疗静脉桥再狭窄已成为目前研究的热点.本文主要从静脉桥再狭窄防治的目的基因、基因导入方式、基因载体等方面,对静脉桥再狭窄基因治疗的研究进展进行综述.     

Interleukin-1 alpha as a factor in occlusive vascular disease.

The purpose of this study was to examine the recognized ability of interleukin-1 alpha (IL-1 alpha) to alter the functional properties of endothelial cells and to induce replication of smooth muscle and fibroblasts. Such changes could potentially link IL-1 alpha pathogenetically to the myointimal proliferation of vascular sclerosis. Using a peroxidase-immunoperoxidase immunohistochemical method, saphenous veins and internal mammary arteries were examined for the presence of IL-1 alpha before their implantation as aortocoronary bypass grafts. Occluded saphenous vein grafts requiring replacement because of recurrent angina pectoris also were similarly examined. Interleukin-1 alpha, deposited as a scarlet immunoprecipitate, was seen on the luminal surface, in the subintima, and on the spindle cells and infiltrating macrophages in the media of 13 phlebosclerotic veins before surgical insertion. The remaining 30 unchanged veins did not contain IL-1 alpha. Similarly, IL-1 alpha was not identified in any of the 43 sampled internal mammary arteries that were all considered structurally intact. All the 55 bypass grafts, which were examined by biopsy during revascularization and demonstrated diverse histopathologic abnormalities consisting of reduced luminal patency, myointimal proliferation, mononuclear cell infiltration, mural collagenization, and luminal-mural hemorrhage, also contained widely distributed IL-1 alpha. The observation that IL-1 alpha was absent in all of the internal mammary arteries concomitant with maintenance of normal microanatomic structure may help explain, in part, their recognized resistance to reduction in luminal patency and their improved clinical survival when used as coronary artery bypass grafts. Alternatively, the consistent presence of IL-1 alpha in all vessels with sclerotic histopathologic changes suggests that this cytokine may be an important in situ indicator of and a potential participant in vascular injury. Interleukin-1 alpha may be a pathogenetic factor in the complex processes leading to vascular occlusion.     

桡动脉在全动脉化冠脉搭桥术中的临床应用

目的探讨桡动脉在全动脉化冠脉搭桥术中的临床应用效果。方法22例患者采用乳内动脉和桡动脉行全动脉化冠脉搭桥手术,"不接触血管技术"游离桡动脉,与冠状动脉对角支、钝缘支、前降支、右冠状动脉等单独或序贯吻合,共搭桥31支。术后应用钙通道阻滞剂防止桡动脉痉挛。结果22例手术均顺利完成,痊愈出院,无围术期心肌梗塞,术后心肌缺血改善,无手部缺血并发症。随访2月～3年,无心绞痛复发,手部功能正常。结论桡动脉作为血管桥材料在全动脉化冠脉搭桥术中应用效果良好。     

冠状动脉旁路移植治疗冠状动脉肌桥9例分析

目的回顾冠状动脉旁路移植术治疗症状性肌桥的外科治疗经验及结果。方法选取2004年3月至2011年1月因冠状动脉肌桥导致冠状幼脉血流堵塞需行冠状动脉旁路移植术的患者资料9例,采用胸廊内动脉到前降支进行旁路移植,2例取大隐静脉与其他病变冠状动脉进行旁路移植。结果全组无患者死亡,无术中相关并发症发生。所有患者随访4个月至7年,临床症状均明显改善,无心绞痛发生,无心肌梗死及其他主要心血管不良事件（再血管化或死亡等）发生。结论冠状动脉旁路移植治疗有症状的肌桥安全、有效。     

On the biology of saphenous vein grafts fitted with external synthetic sheaths and stents

Autologous saphenous vein is used as a conduit to bypass atherosclerotic lesions in both the coronary artery (coronary artery bypass graft surgery [CABG]) and in femoral arteries (infrainguinal bypass graft surgery [IIBS]). Despite the undoubted success and benefits of the procedures, graft failure occurs in 50% of cases within 10 years after surgery. A principal cause of late vein graft failure is intimal and medial hyperplasia and superimposed atherogenesis. Apart from lipid lowering therapy, no intervention has hitherto proved clinically effective in preventing late vein graft failure which clearly constitutes a major clinical and economic problem that needs to be urgently resolved. However, we have studied the effect of external synthetic stents and sheaths in pig models of vein into artery interposition grafting and found them to have a profound effect on vein graft remodelling and thickening. In this review, therefore, we will summarise the mechanisms underlying vein graft failure and how these stents influence these processes and the possible mechanisms involved as well as the application of these devices in preventing vein graft failure clinically.     

Coronary artery bypass grafting for Fabry's disease: veins more suitable than arteries?

Coronary artery bypass grafting was performed in a 54-year-old man affected by untreated Fabry's disease. Left internal mammary artery (LIMA) and saphenous vein grafts were implanted. Surgical samples of LIMA revealed diffuse glycosphyngolipid infiltration of smooth muscle cells, whereas SV was normal. After surgery, the patient received antithrombotic and enzyme replacement therapy. At 1-year follow-up, LIMA graft occluded, whereas saphenous vein graft remained patent. In Fabry's disease, veins, probably because of a low pressure load, seem to be spared from glycosphingolipid accumulation and are more suitable than arteries for grafting. A preventive histology of conduits is suggested before graft selection.     

Understanding and treating vein graft atherosclerosis.

BACKGROUND: Vein grafts have been used as bypass conduits for coronary artery disease since the 1960s. This widely used treatment, however, is complicated by the development of changes in the vein graft, which resemble atherosclerosis and are often termed as such. They occur at about 10 years, which leads to the need for reoperation in some patients. The purpose of this review is to summarize the knowledge regarding the pathophysiology of vein graft "atherosclerosis," as well as promising new treatments for this disease. METHODS: The relevant literature relating to the epidemiology, histology, cell and molecular pathophysiology and treatment of vein graft atherosclerosis is reviewed. RESULTS: The development of vein graft atherosclerosis differs from arterial atherosclerosis. Studies have examined the role of trauma, lipids, vasoactive mediators, smooth muscle cell mitogens, smooth muscle cells apoptosis, adhesion molecules and proteases. Therapies have been developed to prevent vein graft atherosclerosis based on these studies and have been tested using animal models and in patients. DISCUSSION: Promising new therapies have been developed based on current knowledge and further applications of genomics will allow for the further identification of risk factors and mechanistic insights. The use of arterial grafts such as the internal mammary artery, which have higher patency rates at 10 years compared with vein grafts as well as approaches to revascularize infarcted myocardium may one day replace the use of vascular conduits.