Pathology of hearts after aortocoronary saphenous vein bypass grafting for coronary artery disease, studied by post-mortem coronary angiography.

A detailed pathological study was made in 10 patients dying up to 13 months after aortocoronary saphenous vein bypass grafting for coronary atherosclerosis. The coronary arteries and vein grafts were investigated by injection with a radio-opaque mass, radiography, dissection, and histology. The report is to some extent historical since the patients died during a period when the operation was first being introduced into two cardiothoracic hospitals. About 80 operations were performed during the time the 10 deaths occurred, a mortality of 12-5 per cent (including cases followed up to 13 months after operation). Seven of the patients were operated on for intractable angina and 3 with a view to aneurysmectomy. All the patients selected for operation were severely disabled despite medical treatment. The main cause of death was extremely severe coronary artery disease and its effects on the left ventricle; in one case, over two-thirds of the left ventricle had been destroyed by infarction before operation. Other causes or contributing causes of death were pulmonary embolism, myocardial infarction complicating angiography (ostial stenosis), and cerebral damage. Ten of the 14 vein grafts (71%) were patent at necropsy. A free flow of injection medium usually occurred between patent grafts and coronary arteries. Thrombosis of a graft was thought to have contributed to death in 3 patients, but not in a fourth who died of pulmonary embolism. Since thrombosis of grafts was usually secondary to poor run-off blood into severely atheromatous coronary arteries, this was also an indirect effect of the advanced coronary arterial disease. In one case, thrombosis followed severe chronic intimal thickening of a graft in place for 13 months. The study of these deaths emphasizes that in some patients the pathological changes in the coronary arteries and left ventricle are too severe for them to benefit from surgery. Vein grafts cannot be expected to distribute blood effectively through grossly narrowed coronary arteries. In addition, when a large part of the left ventricle is infarcted or scarred, it is almost certain that improving the blood supply by grafting will not result in significant regeneration of cardiac muscle. Since the time when this study was made, there have been few deaths among the many vein graft operations subsequently carried out in the hospitals involved. The two most important factors thought responsible for the improvement are the selection of cases more suitable for surgery by continued improvement of diagnostic techniques, and also the employment of more radical surgical procedures in the form of coronary endarterectomy and the insertion of more grafts per patient.     

Ruptured saphenous vein graft aneurysm after aortocoronary bypass grafting

Computed tomography demonstrated a giant saphenous vein graft aneurysm that compressed the right atrium of a 72-year-old woman 20 years after undergoing coronary artery bypass grafting. Angiography revealed contrast medium leakage in the mid-portion of the graft aneurysm. Aneurysmectomy was performed without repeat grafting. Postoperative myocardial scintigraphy demonstrated no significant myocardial ischemia. The ischemic effect of non-revascularization should be considered preoperatively because of the difficulties with repeat grafting.     

Radial artery or saphenous vein for coronary artery bypass grafting

Coronary artery disease (CAD) is the most common cardiovascular disease worldwide, affecting over 18 million American adults. Coronary artery bypass grafting (CABG) is the standard of care for patients with left main or triple vessel CAD. Historically, the saphenous vein (SV) has been utilized to bypass the majority of the coronary vessels in patients undergoing CABG, but more recent data suggest that the use of the radial artery (RA), rather than the SV, is associated with improved cardiac outcomes and better survival. The aim of this review is to summarize the current literature on the use of RA and SV for CABG in patients with multivessel CAD.     

Enhanced rate of progression of coronary artery disease following aortocoronary saphenous vein bypass surgery

To evaluate the fate of the coronary arteries after aortocoronary bypass, 40 patients underwent serial selective coronary angiographic studies 1 year apart, and the frequency of progression of coronary artery disease was estimated. Thirty-two had saphenous vein bypass surgery after the first procedure, six had Vineberg operations, and two had no interim operation. In each patient, the right, left, anterior descending and circumflex coronary arteries (including their branches) were separately evaluated. Progressive narrowing was evident in 31 of 50 (62 per cent) bypassed vessels and in only 11 of 113 (9.7 per cent) nonbypassed arteries (p < 0.001). Coronary arteries with moderate to severe obstruction initially (50 to 99 per cent occluded) manifested progressive disease more frequently (33 of 70 arteries) than did arteries that were normal or mildly narrowed initially (4 of 71) (p < 0.001). Considering only those vessels with 50 to 99 per cent obstruction initially, 27 of 35 (77 per cent) of the bypassed arteries and only 6 of 35 (17 per cent) of the nonbypassed arteries showed progression (p < 0.001). We conclude that moderately or severely narrowed coronary arteries are more likely to show progressive narrowing than normal or mildly obstructed ones and that progression of coronary disease is greater in bypassed vessels than in nonbypassed vessels. In view of potential graft closure, the implications of these findings must be considered in selecting patients for aortocoronary bypass.     

Endoscopic harvesting of the greater saphenous vein for aortocoronary bypass grafting.

We conducted an observational study to evaluate the effectiveness of an endoscopic technique for harvesting the greater saphenous vein for aortocoronary bypass grafting. We hypothesized that the endoscopic technique would minimize the risk of postoperative wound complications. From May 1997 to July 1998, we used an endoscopic technique to harvest the greater saphenous vein in 50 patients who underwent aortocoronary artery bypass grafting. Twenty-five of the patients had an increased risk for wound complications due to preexisting diabetes, obesity, peripheral vascular disease, or lymphedema. The average duration of the procedure was 39 minutes (range, 11 to 70 minutes). The average length of the harvested vein was 58 cm (range, 25 to 85 cm). We made an average of 2.5 incisions per patient (range, 1 to 5 incisions), and the average incision length was 7 cm (range, 3 to 10 cm). Two patients (4%) required conversion to an open technique using 5 small incisions. Postoperative complications included 1 wound infection (2%) and 1 small hematoma (2%). Two patients (4%) had minor erythema at the incision site, and 5 patients (10%) had postoperative lymphedema. The most common problem, ecchymosis, was seen in 6 patients (12%). None required repeat hospitalization or reoperation for wound complications. In our study, the endoscopic approach yielded superior cosmetic results, and reduced wound complications and discomfort, compared with traditional methods of vein harvesting. After gaining expertise with this minimally invasive method of vein harvesting, a surgeon can safely remove the saphenous vein in 20 to 30 minutes.     

Atrial pacing during selective aortocoronary saphenous vein bypass angiography

Selective aortocoronary bypass graft angiography was performed in 30 postoperative subjects. Thirty-one of 39 patent graft injections resulted in cardiac arrhythmias including sinus bradycardia, premature ventricular depolarizations, sinoatrial arrest and atrioventricular (A-V) block. In contrast, only 2 of 39 graft angiograms performed during right atrial pacing produced arrhythmias. We conclude the following: (1) Routine prophylactic right atrial pacing is a valuable method for preventing certain cardiac arrhythmias during aortocoronary graft opacification; and (2) the potential for rapid institution of right ventricular pacing provides safety in the event that angiographically induced A-V block occurs.     

桡动脉-大隐静脉组合V形桥在冠状动脉旁路移植术中的应用

目的:对桡动脉-大隐静脉组合V形桥新术式的安全性和近期移植血管通畅率进行初步探讨。方法:选自2015年4月至2016年3月,我院共完成29例桡动脉-大隐静脉组合V形桥冠状动脉旁路移植(CABG)术。平均年龄(65. 3±8. 2)岁,女性4例(16%)。将大隐静脉与升主动脉做近端吻合,桡动脉与该大隐静脉端侧吻合,吻合口距升主动脉的距离≤0. 5 cm。对术后30 d死亡率,桡动脉-大隐静脉组合V形桥吻合口以及远端吻合口的近期通畅性(术后6个月)进行影像学评价。结果:术后30 d死亡率为零;术后6个月对桡动脉-大隐静脉组合V形桥吻合口及远端吻合口的通畅性应用冠状动脉CTA进行评价,通畅率均为100%。结论:桡动脉-大隐静脉组合V形桥CABG术是一种安全有效的新术式,临床效果满意,近期通畅率高。     

冠状动脉旁路术中药物扩张大隐静脉的优越性

目的探讨冠状动脉旁路术(CABG)中药物扩张大隐静脉的效果。方法将异搏定10mg、硝酸甘油5mg、5%碳酸氢钠1.0ml、肝素12500U加入林格氏液至500ml配成等渗溶液。22例接受CABG患者在术中暴露大隐静脉时,将此溶液灌注至静脉腔内,同时浇注于静脉表面,并将切取的静脉浸泡于该溶液中。另取同一患者邻近部位的一段大隐静脉作对照,采用加压灌注法扩张,比较两种方法处理的静脉管壁厚度,光镜下血管壁结构的变化。结果压力扩张的静脉管壁变薄;药物扩张使平滑肌舒张,血管腔均匀性扩大。光镜下加压组内皮细胞大量脱落,固有膜细胞水肿明显,肌层细胞出现粘液变性;药物组静脉管壁结构完整。结论药物扩张的大隐静脉管壁结构完整,管腔足够大,有利于桥血管的近、远期通畅。     

冠状动脉旁路术中药物扩张大隐静脉的优越性

目的:探讨冠状动脉旁路术(CABG)中药物扩张大隐静脉的效果. 方法:将异搏定10mg、硝酸甘油5 mg、5%碳酸氢钠1.0ml、肝素12 500 U加入林格氏液至500ml配成等渗溶液.22例接受CABG患者在术中暴露大隐静脉时,将此溶液灌注至静脉腔内,同时浇注于静脉表面,并将切取的静脉浸泡于该溶液中.另取同一患者邻近部位的一段大隐静脉作对照,采用加压灌注法扩张,比较两种方法处理的静脉管壁厚度,光镜下血管壁结构的变化. 结果:压力扩张的静脉管壁变薄;药物扩张使平滑肌舒张,血管腔均匀性扩大.光镜下加压组内皮细胞大量脱落,固有膜细胞水肿明显,肌层细胞出现粘液变性;药物组静脉管壁结构完整. 结论:药物扩张的大隐静脉管壁结构完整,管腔足够大,有利于桥血管的近、远期通畅.     

冠状动脉旁路移植术后静脉桥狭窄的研究进展

冠状动脉旁路移植术是冠状动脉粥样硬化性心脏病的常规治疗方法之一.动脉血管作为移植血管材料有其自身优势,但对大多数患者而言,自体大隐静脉仍然是最常用的移植血管材料.新内膜形成和动脉粥样硬化导致的静脉桥再狭窄已成为一个亟待解决的问题.主要的防治方法包括药物、血管外支架、扩张液和基因治疗等,其中基因治疗为再狭窄的防治带来了新的前景.     

Myocardial infarction after aortocoronary saphenous vein bypass. Vectorcardiographic study.

Vectorcardiograms and scalar electrocardiograms were recorded in 30 patients before and after aortocoronary saphenous vein bypass surgery to determine whether vectorcardiograms are helpful in making the diagnosis of perioperative transmural infarction. The vectorcardiogram indicated inferior infarction in 2 cases and anterior infarction in 1 case when the diagnosis was not apparent on the electrocardiogram. In the solitary case of anterior infarction diagnosed by the electrocardiogram, anterior infarction was already present on the preoperative vectorcardiogram. The study indicates that the recording of vectorcardiograms before and after aortocoronary bypass surgery facilitates the diagnosis of perioperative anterior and inferior infarction and may reveal perioperative infarction about a previously infarcted area.     

Myocardial infarction after aortocoronary saphenous vein bypass. Vectorcardiographic study.

Vectorcardiograms and scalar electrocardiograms were recorded in 30 patients before and after aortocoronary saphenous vein bypass surgery to determine whether vectorcardiograms are helpful in making the diagnosis of perioperative transmural infarction. The vectorcardiogram indicated inferior infarction in 2 cases and anterior infarction in 1 case when the diagnosis was not apparent on the electrocardiogram. In the solitary case of anterior infarction diagnosed by the electrocardiogram, anterior infarction was already present on the preoperative vectorcardiogram. The study indicates that the recording of vectorcardiograms before and after aortocoronary bypass surgery facilitates the diagnosis of perioperative anterior and inferior infarction and may reveal perioperative infarction about a previously infarcted area.     

Metabolic damage to human saphenous vein during preparation for coronary artery bypass grafting

Segments of saphenous vein from patients undergoing coronary artery by-pass graft surgery were frozen in liquid nitrogen immediately on dissection (control), after stripping of the adventitia and side branch ligation (manipulation), after distention with blood (distention), or at completion of the last proximal anastomosis (prepared vein). Vein was stored during the operation in patient's heparinised arterial blood at room temperature. Frozen vein was extracted with perchloric acid. ATP, ADP, and AMP, adenosine, inosine and hypoxanthine concentrations were measured by high pressure liquid chromatography. Prepared vein had ca 50% lower ATP concentrations and ATP/ADP ratio than control vein, higher concentrations of inosine and hypoxanthine and lower concentrations of AMP and adenosine. ATP concentration and ATP/ADP ratio did not correlate with the time elapsed between dissection and freezing of the prepared vein. The characteristic changes seen in prepared vein were not seen when control vein was simply stored in arterial blood at 23 degrees C, in normal saline at 23 degrees C or 4 degrees C, in Krebs-Ringer bicarbonate buffer at 37 degrees C or at St Thomas's Hospital cardioplegic solution at 4 degrees C. Distention with unlimited pressure did not distension at less than 300 mmHg gave rise to the same changes in ATP concentration and ATP/ADP ratio as in the prepared vein. These results show that vein suffered metabolic changes during preparation for bypass grafting and suggest that uncontrolled distention may contribute to these changes. Such biochemical measurements provide a quantitative estimate of tissue damage and allow objective comparison of different preparative techniques.     

Scoring system for predicting saphenous vein graft patency in coronary artery bypass grafting

The initial and long-term benefits of coronary artery bypass grafting depend upon maintaining the coronary blood flow supplied by the graft. In order to devise a scoring system for predicting graft patency, we evaluated presumptive correlations between saphenous vein graft patency and the characteristics of saphenous veins that were used as conduits in coronary revascularization.We prospectively evaluated 1,000 saphenous vein segments that were implanted in 403 consecutive patients who underwent on-pump coronary artery bypass grafting at our hospital from January 2006 through February 2009. Branches, varicosity, diameter, and wall thickness were evaluated, and a scoring system was created in order to obtain a value for each characteristic. The patients were postoperatively monitored for 1 year, and graft patency was then evaluated with the use of 64-slice multidetector computed tomography.Lesions were found in 12.3% of the grafts. All of the evaluated characteristics of the grafts had a significant correlation with saphenous vein graft flow (P <0.0001). Using the venous characteristics in our statistical analysis, we devised a formula to obtain a score (range, 4-12) to predict the patency of each graft. A cutoff score of 7 yielded 87.8% sensitivity and 82.8% specificity.Our scoring system has good prognostic value. We believe that it can assist surgeons in choosing the most appropriate conduit and target vessel for coronary artery bypass grafting, especially in high-risk patients who are particularly dependent on blood flow through saphenous vein grafts.     

内窥镜采集大隐静脉在冠状动脉旁路移植术后近、中期的疗效分析

目的比较冠状动脉旁路移植术（CABG）中应用内窥镜采集与直视切开采集大隐静脉的近、中期临床效果。方法纳入2005年4月~2010年1月行CABG治疗且随访资料完整的冠心病患者268例。根据大隐静脉的采集术式分为两组,使用内窥镜采集大隐静脉的患者进入内镜组（EVH组,n=129）,采用直视切开采集大隐静脉的患者进入切开组（OVH组,n=139）,应用64排螺旋CT（64-MSCT）对比分析手术后3个月、1年、3年大隐静脉桥通畅率。结果 EVH组与OVH组术后3个月、1年、3年大隐静脉桥通畅率均无统计学差异[分别为（88.0%vs.85.6%）,（78.9% vs.79.9%）,（72.2% vs.71.8%）, P＜0.05],但EVH组采集时间更长[（50.23±5.87）min vs.（38.65±7.96）min],破损情况更多[（1.51±0.19） vs.（0.84±0.04）],差异有统计学意义（P＜0.05）。结论内窥镜和直视切开两种采集方式的大隐静脉桥近、中期通畅率接近,但内窥镜法采集时间较长,静脉破损较多。