The radial artery for coronary artery bypass grafting

Coronary artery bypass grafting (CABG) is the standard surgical procedure for the treatment of advanced coronary artery disease. CABG surgery has been demonstrated to improve symptoms and, in specific subgroups of patients, to prolong life. Despite its success, the long-term outcome of coronary bypass surgery is strongly influenced by the fate of the vascular conduits used. Previous long-term studies have shown unsatisfactory patency of saphenous vein grafts used for myocardial revascularisation, compared with internal mammary artery grafts. Recently, the use of radial artery for CABG has enjoyed a revival, on the basis of the belief that it will help improving long-term results of coronary operations. The recent reports of encouraging mid-term and long-term patency rates of the radial artery, supports its continued use as a bypass conduit. In this paper, we review the current knowledge about the radial artery as a bypass graft, with special emphasis on the clinical results.     

An Evaluation of Histomorphometric Properties of Coronary Arteries,Saphenous Vein,and Various Arterial Conduits for Coronary Artery Bypass Grafting

Purpose. We evaluated the histomorphological properties of the coronary arteries, saphenous vein, and five arterial conduits for coronary artery bypass grafting, and compared them with each other. Methods. All vessels were harvested from seven cadavers, eight autopsied individuals, and 14 patients. The length, lumen diameter, wall thickness, and histological structures were examined based on samples obtained from the coronary arteries and the conduits. The dimensions and wall thicknesses of the coronary arteries and the conduits were compared using a one-sided variance analysis. The similarities between the coronary arteries and the conduits were investigated by Duncan's multiple range tests. Results. The internal mammary and intercostal arteries were elastic, while the others were muscular. The lengths of all conduits were adequate for use as coronary artery grafts. The dimensions and wall thicknesses of the coronary arteries and the conduits showed no statistically significant differences, except for the proximal portion of the saphenous vein. Conclusions. These findings emphasize the justification of continued use of the ideally matching internal mammary artery, either as an in situ or free graft, in coronary artery bypass grafting, although other arterial grafts can be used in coronary artery bypass grafting. In addition, the intercostal artery was found to have relatively favorable properties regarding its potential suitability as a coronary bypass conduit.     

The fate of the radial artery conduit in coronary artery bypass grafting surgery.

Coronary artery bypass grafting (CABG) is the standard surgical procedure for the treatment of advanced coronary artery disease. CABG surgery has been demonstrated to improve symptoms and, in specific subgroups of patients, to prolong life. Despite its success, the long-term outcome of coronary bypass surgery is strongly influenced by the fate of the vascular conduits used. Impressive long-term disease-free patency rate of the left internal thoracic artery-left anterior descending coronary artery (LITA-LAD) graft, coupled with proven long-term survival benefits, has led to its becoming a 'golden standard' of CABG. Previous long-term studies have also shown unsatisfactory patency of saphenous vein grafts used for myocardial revascularization, compared with internal thoracic artery grafts. Thus, the use of arterial conduits has expanded beyond the internal thoracic arteries (ITAs) to include the right gastroepiploic artery, the inferior epigastric artery, and the radial artery. The assumption is that although the performance of one or two arterial ITA graft is superb, more arterial grafts should perform better in the long-term follow-up. Several studies concerning the use of the radial artery bypass grafts have documented excellent clinical results and satisfactory short-term as well as mid-term patency rates at restudy angiography, supporting its continued use as a bypass conduit. However, a note of caution concerning radial artery conduit patency rate have appeared in few recent reports. Thus, in this paper, we summarize the current evidence about the radial artery as a conduit in CABG surgery, with special emphasis on the clinical results.     

Long-term left internal mammary artery graft patency for coronary artery disease associated with pseudoxanthoma elasticum

Pseudoxanthoma elasticum (PXE) is a rare, inherited connective tissue disorder with numerous systemic manifestations that include premature coronary artery disease. Coronary artery bypass grafting (CABG) is known to be beneficial in patients with PXE-related coronary artery disease. In these patients, however, the suitability of arterial conduits, including the internal mammary artery, has been controversial. We present a patient with PXE-related coronary artery disease who has had long-term patency of a left internal mammary artery (LIMA) graft after an off-pump CABG procedure in which LIMA and bilateral radial artery conduits were used.     

Vascular Prosthese s for Aortocoronary Bypass Grafting: A Review

Abstract: Alternative conduits must be chosen when autologous grafts are not available for coronary artery bypass grafting (CABG). Viable grafts do not always have perfect characteristics for CABG, and homologous venous conduits have been used with unsatisfactory results. Many small caliber vascular grafts used for coronary bypass conduits have been developed in the past, but most of them have failed except in rare instances. In this paper the current problems in available conduits, new technologies for improvement, animal models, and possibilities for the future for CABG conduits are discussed.     

Techniques for multiple internal mammary artery bypass grafts

Long-term patency of the internal mammary artery graft surpasses that of all other bypass conduits. The use of multiple internal mammary artery grafts should improve the long-term results following coronary artery bypass grafting. Technical factors used in mobilizing, preparing, and anastomosing the internal mammary artery are discussed in this article. Fifty-three patients received sequential attached left internal mammary artery grafts from April, 1982, to August, 1983. In 6 of these patients, the right internal mammary artery was anastomosed to a circumflex marginal branch. There were no operative deaths or instances of low cardiac output. One patient suffered anastomotic narrowing that possibly could have been prevented by excision of excess tissue from the internal mammary artery pedicle. Multiple internal mammary artery grafting should have a profound influence on the results of coronary artery bypass grafting.     

Arterialization in coronary artery surgery in Japan and Hong Kong

In the 35 years of coronary artery bypass grafting, several kinds of conduits have been utilized and assessed. It is clear now that the saphenous vein graft deteriorated with time mainly due to atherosclerosis in the graft called "vein graft disease." The internal thoracic artery graft, on the contrary, stays patent very well in the long-term period and this evidence directly related to the superior later outcome in terms of longevity and postoperative cardiac events. To extend the use of arterial conduits for myocardial revascularization, several autologous arteries have been investigated and utilized clinically. With proper use of these new arterial conduits in addition to internal thoracic artery, coronary artery bypass grafting with multi-arterial grafts can be performed safely, and better long term result can be expected.     

The Technique of Radial Artery Bypass Grafting and Early Clinical Results

There is renewed interest in the use of the radial artery as a conduit for coronary artery bypass. Fifty patients underwent bypass surgery using the radial artery in addition to other conduits between November 24, 1992 and November 8, 1994 at our institution. The mean age was 54.4 ± 9.1 years (mean ± SD) and 47 of the patients were male. There were 3.6 ± 0.9 anastomoses per patient, of which 2.2 ± 0.4 were arterial anastomoses. The most common target vessel for the radial artery has been the obtuse marginal (58.8%), with the aorta as the usual site for proximal anastomosis (80.4%). There have been no ischemic hand complications and no radial nerve deficits. There have been no early or late deaths and no myocardial ischemic complications related to the use of the radial artery. We present the techniques used at our institution for the use of the radial artery as a conduit for coronary artery bypass.     

A new technique for the old arterial graft: internal thoracic artery

The internal thoracic artery (ITA) is the gold-standard conduit for coronary artery bypass surgery. It stays patent well in the long-term period, and this evidence is directly related to the superior later outcome in terms of longevity. Coronary artery bypass grafting with multiarterial grafts can be performed safely, and better long-term result can be expected with the use of arterial conduits, especially ITA. We describe a simple and practical technique for the left ITA grafting by dividing the ITA graft and using its proximal and distal parts in situ for the distal left anterior descending (LAD) artery and the obtuse marginal artery grafting.     

Myocardial revascularization with the posterior tibial artery

A large number of coronary artery bypass grafts are performed in Thailand. Some patients develop restenosed coronary arteries or stenosed graft conduits. Great saphenous veins, internal thoracic arteries, radial arteries, and right gastroepiploic arteries are used for redo coronary artery bypass grafting. But even with many conduits to choose from, sometimes graft conduits are not available. We report a case of redo coronary artery bypass grafting where the posterior tibial artery was harvested for the graft conduit. Clinical outcome and angiographic results are reported at 1 year postoperation.     

Patient Selection and Results of Simultaneous Coronary and Carotid Artery Procedures

The high incidence of severe coronary artery disease in patients with symptomatic carotid artery disease makes careful evaluation of both carotid and coronary systems important to the successful short-term and long-term management of these patients.We have established guidelines for patient evaluation and procedure selection based on symptomatic assessment of each system, supplemented by angiographic and hemodynamic data. With this information, three operative groups are established: (1) carotid artery operation first or alone, (2) coronary artery bypass grafting first followed by carotid artery operation, and (3) simultaneous carotid artery and coronary artery bypass procedures. The benefit of this selection process has been shown by the low operative mortality in each group. This report presents our selection process and evaluates the results for 21 patients in the group having simultaneous carotid and coronary artery procedures.     

Vascular antispastic medication should take priority over other antihypertensives after coronary artery bypass grafting using a radial artery conduit

Radial artery conduits have recently been used more often in coronary artery bypass grafting because of their potentially better long-term patency than saphenous vein conduits. However, vasospasm of the radial artery conduit due to its nature as a muscular artery has always been of concern and a variety of vasodilators have empirically been used to reduce the risk of spasm. When a patient who was preoperatively taking antihypertensive agents undergoes coronary artery bypass using a radial artery graft, and if he/she is not hypertensive postoperatively, it is not always easy to decide what medication to start with. We report a case of a patient with a radial artery graft who did not receive vasodilators after surgery due to hypotension. The patient developed vasospasm of the radial artery conduit which did not respond to direct injection of vasodilators into the conduit but recovered after taking oral vasodilators for four weeks.     

Coronary artery bypass grafting with gastroepiploic artery composite graft

BACKGROUND: To achieve better results after coronary artery bypass grafting (CABG), arterial conduits are the first choice in multiple CABG for younger patients. We present here the early results of CABG with gastroepiploic artery (GEA) composite graft with free radial artery (RA) to revascularize right coronary artery or left circumflex artery in addition to internal thoracic artery to left anterior descending artery. METHODS: Between July 1997 and June 1998, 13 patients received CABG with GEA (larger caliber than 2.0 mm) composite graft. We have assessed the early results. RESULTS: There was no postoperative death or major morbidity. Postoperative angiogram was performed in 11 patients and all conduits were patent. Postoperative exercise stress test was done in 13 cases and showed no ischemia. CONCLUSIONS: Multiple CABG with arterial conduit can be performed by this procedure. The free RA functioned from secondary branches derived from proximal GEA. In conclusion, this procedure seems to be safe and effective, and both long-term patency and better quality of life may be expected.     

Coronary artery bypass grafting with the right gastroepiploic artery

The excellent results of coronary artery bypass with the internal mammary artery and the increasing numbers of patients who need coronary reoperations, but for whom conventional bypass conduits are not available, have prompted us to evaluate alternative arterial bypass conduits. The right gastroepiploic artery has been used as a coronary bypass graft in 36 patients (32 men), whose ages ranged from 29 to 71 years. Twenty-two patients had had previous coronary bypass grafting and six of these were undergoing their third bypass operation. The right gastroepiploic artery was used as an in situ graft to the right coronary artery or circumflex branches for 17 patients and as an aorta-coronary ("free") graft in 19 patients, six to the left anterior descending or diagonal, six to the circumflex, and seven to the right coronary artery. In conjunction with right gastroepiploic artery grafting, 16 patients received bilateral internal mammary artery grafts and 17 received one internal mammary artery graft. Histologically, right gastroepiploic artery segments from 18 patients could not be distinguished from internal mammary artery segments, and no evidence of atherosclerosis was found. Two patients died in the hospital, one intraoperatively and one 3 months after the operation, of a perioperative stroke. Perioperative morbidity included wound complication in three and reexploration for bleeding in two. At late follow-up 1 to 38 months after operation, two late deaths had occurred and 21 patients were free of symptoms. Postoperative angiography (postoperative interval 1 week to 13 months) was performed in nine grafts, three in situ grafts to the right coronary artery and six free grafts that included two to the left anterior descending, three to the circumflex, and one to the right coronary artery. All right gastroepiploic artery grafts were patient. The right gastroepiploic artery is an arterial conduit that can be used as an in situ graft to posterior coronary vessels and as a free graft to any coronary arterial system. Early graft patency has been excellent, and the histologic similarity between the right gastroepiploic artery and the internal mammary artery suggest that the long-term results will be favorable.     

Internal thoracic artery: to skeletonize or not to skeletonize?

The internal thoracic artery has been the most reliable graft material used in coronary artery bypass grafting with an excellent long-term patency rate. Complete myocardial revascularization with internal thoracic arteries improves long-term survival and decreases the rate of repeat operations compared with vein grafts. Adequate length of the graft in coronary artery bypass graft surgery is essential for providing complete arterial revascularization. In the last decade or so, technique of skeletonization of internal thoracic artery has been proposed to achieve extra length. Skeletonization of the internal thoracic artery allows the preparation of longer conduits with a superior free flow and can reduce the incidence of postoperative pulmonary and sternal complications. However, concerns about vasoreactivity of skeletonized internal thoracic artery grafts, the functional consequences of surgical trauma, the possible loss of innervation, and vasa vasorum perfusion in the skeletonized conduits have prevented this technique from being universally accepted. Presently available evidence from retrospective studies (level 3 evidence) suggests that skeletonization is a safe and effective technique for myocardial revascularization. However, there is a need for conducting multicenter, randomized controlled trials comparing the skeletonized and pedicled internal thoracic arteries with special emphasis on long-term patency to conclusively validate the safety and efficacy of skeletonization technique.     

Mid-term angiographic comparison of sequential and individual anastomosis techniques for diagonal artery

OBJECTIVE: The mid-term patency rates for individual and sequential grafts as coronary bypass conduits for diagonal arteries were angiographically compared; the impact of native coronary vessel and type of the conduit characteristics are investigated. METHODS: Between March 1992 and April 2000, we performed a total number of 811 distal anastomosis on diagonal arteries of left anterior descending (LAD) artery in 296 patients who underwent coronary artery bypass surgery (CABG) distal anastomosis in our clinic. The patients were divided into two groups in this prospective study. In group A (n = 195) individual anastomosis technique, in group B (n = 101) sequential anastomosis technique was chosen as the myocardial revascularization strategy. At an average of 49.4 +/- 13.2 months after coronary revascularization procedure coronary angiographies were evaluated. Individual and sequential grafting techniques were compared by graft patency rates. RESULTS: The patency rates of sequential conduits were markedly higher than those of individual conduits (66.7% vs. 89.2%, p = 0.0001). This difference was also clear in coronary arteries with poor quality and small (<1.5 mm) diameter (49.1% vs. 66.6%, p = 0.032). Also, the patency rates of sequential radial artery conduits were higher than sequential saphenous vein graft (SVG) conduits (sequential radial artery; 94.1%, sequential SVG; 85.3%, p = 0.043). CONCLUSIONS: Sequential grafting for diagonal artery is technically more demanding but the mid-term results are better than individual grafting especially in coronary arteries with poor quality. Using radial artery as a sequential graft increases the mid-term graft patency rates.     

Technical Considerations and Early Results of Sequential Left Internal Mammary Artery Bypass Grafting to the Left Anterior Descending Coronary Artery System

The use of the internal mammary artery (IMA) as a coronary artery bypass graft conduit has recently been expanded to include sequential bypass grafting of multiple vessels. This has the theoretical advantage of allowing a greater percentage of myocardium to be revascularized with a conduit that has superior long-term patency rates. This article reviews technical considerations including maximizing IMA graft length and diameter, avoidance of an acute mediastinal or epicardial course, as well as anastomotic techniques for optimizing results of sequential IMA bypass grafting to the left anterior descending coronary artery system.     

Less Invasive Coronary Artery Bypass Without Cardiopulmonary Bypass

Minimally invasive coronary artery bypass grafting (CABG) aims to avoid cardiopulmonary bypass and take maximum advantage of a smaller incision. Minimally invasive direct coronary artery bypass (MIDCAB) surgery is performed on selected arteries of the beating heart under direct vision through a choice of small incisions. Short-term results show good patency rates and a dramatic impact in terms of shorter hospital stays and cost effectiveness. The procedure is also being used increasingly in Japan. However, valid concerns have been raised about the quality of the anastomosis fashioned on a beating heart with pharmacologic bradycardia, and the long-term result of this technique is still questionable. The combined use of circulatory assist devices and mechanical stabilizing devices will be expected to expand access to coronary arteries by allowing for decompression of the left ventricle, permitting retraction and rotation of the heart, and hopefully further improvement of the results. Less invasive coronary surgery should be proven to be as effective and safe as conventional CABG before widespread adoption.     

The Subscapular Artery: An Alternative Conduit for Coronary Bypass

The search for an alternative conduit for coronary bypass has prompted our use of the subscapular artery for coronary bypass via a left thoracotomy in three patients. Historically, this artery in conjunction with muscle flaps has been used successfully as a free graft. Its size and length have proved feasible for coronary bypass to the circumflex coronary artery system. All three patients have had excellent clinical results lasting from 6 to 21 months.     

非体外循环冠状动脉旁路移植术后大隐静脉序贯桥与单支桥中期通畅率的比较

目的比较非体外循环冠状动脉旁路移植术（OPCAB）后大隐静脉序贯桥与单支桥的中期通畅率,评价序贯吻合技术在OPCAB的应用效果。方法回顾性分析2005年6月至2009年3月中国人民解放军总医院398例冠心病患者分别采用大隐静脉序贯桥和单支桥行OPCAB的临床资料,其中男301例,女97例;年龄53～82岁（63.6±10.3岁）。患者于术后3个月～5年（19.8±23.6个月）行64层螺旋CT血管造影（64-MSCTA）检查,共有448支大隐静脉桥上的714个远端吻合口接受评估,分别比较血管桥血流、血管桥及吻合口的通畅率,并分析不同位置对吻合口通畅率的影响。结果大隐静脉双支序贯桥（37.11±16.70ml/min vs.25.15±14.24ml/min,P=0.042）和3支序贯桥（37.56±19.58ml/min vs.25.15±14.24ml/min,P=0.048）的近段血流速度均显著高于单支桥。序贯桥总吻合口通畅率高于单支桥（95.1%vs.90.1%,P=0.013）。序贯桥中间吻合口通畅率分别高于序贯桥远端吻合口（97.0%vs.93.1%,P=0.002）和单支桥远端吻合口（97.0%vs.90.1%,P=0.041）。序贯桥远端吻合口通畅率与单支桥比较差异无统计学意义（P=0.253）;不同吻合方式下各冠状动脉系统（左前降支系统、右冠状动脉系统和回旋支系统）间差异无统计学意义,序贯桥吻合口在右冠状动脉系统的通畅率高于单支桥吻合口（P=0.008）。结论 OPCAB术后大隐静脉序贯桥的中期通畅率较单支桥更满意,序贯吻合时应尽量选择条件较好的靶血管作为序贯桥的最远端血管,条件较差的血管放在序贯桥的中间