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.     

Mid-term angiographic results of radial artery (RA) graft in CABG: Does the proximal site of anastomosis affect graft patency?

Background Use of arterial conduits in coronary artery bypass grafting (CABG) is based on the documented excellent patency rates of left internal thoracic (mammary) artery (LITA). Alternative arterial conduits such as radial artery and gastroepiploic artery also showed superior long-term patency rates compared to vein grafts. Free arterial grafts are being used increasingly to replace the long saphenous vein as a conduit. This study was undertaken to compare two methods of radial artery grafting as a free graft and a composite graft. Methods Between January 1997 and October 2003 a total of 441 patients were operated for coronary artery bypass grafting using radial artery (RA) as one of the conduits. Among these patients, 125 patients received radial artery as a composite graft; In 68 patients RA was used with left internal thoracic artery as a composite y graft (n=68), and in 57 patients it was used with right internal thoracic artery (RITA) as an in situ composite pedicle graft (n=57). In the remaining 316 patients the radial artery was used as a free graft. Angiographic evaluation of radial artery graft was carried out in 63 patients who consented. Angiograms were carried out after an interval of 6–72 months (mean of 28.15±21.17 months). Of these 63 patients who underwent reangiography, the different surgical strategies used were RITA+RA composite in situ graft (n=34), LITA+RA composite y graft (n=17) and aorto coronary (free) RA graft (n=12). Results There were 3 hospital deaths in the series 441 patients. Among the 63 patients who underwent check angiography 60 patients were in NYHA C1 I and 3 patients were in C1 II. None of the patients had perioperative myocardial infarction. Angiographically overall radial artery graft patency rate was 94.1% (59 patients). In patients with RITA and RA in situ grafts patency rate was 94.1%, LITA+RA composite y graft patency was 94.1% and aorto coronary (free) radial artery grafts patency was 91.6%. Conclusion In 63 selected asymptomatic patients studied, we found that radial artery graft when used as an aortocoronary (free) graft or as a composite y graft with left internal thoracic artery or in situ pedicle graft with right internal thoracic artery the patency rates were comparable in all three groups.     

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.     

Saphenous vein: advances

Although the saphenous vein (SV) is a widely used conduit for coronary artery bypass graft surgery (CABG), lower long-term graft patency rates and worse clinical outcomes have been reported after CABG performed with SV grafts compared with CABG performed with internal thoracic artery (ITA) grafts. Of various efforts to overcome the limitations of SV that are resulting from structural and functional differences from arterial conduit, recent improvement in harvesting techniques including no-touch technique, surgical strategy of using the SV as part of a composite graft over an aortocoronary bypass graft, and external stenting of the SV will be discussed in this topic.     

Redo coronary artery bypass grafting using the patent left internal thoracic artery graft as an in flow with composite internal thoracic artery Y grafting; report of a case

In redo coronary artery bypass grafting (CABG), graft selection and revascularization methods are major problems. We experienced a redo-CABG with occluded previous vein grafts. These grafts were to the circumflex artery and right coronary artery. We conducted operation using cardiopulmonary bypass. We at this operation, chose right internal thoracic artery (RITA) as a conduit and anastomosed it to the side of functioning left internal thoracic artery (LITA) graft, and then diogonal branch, posterolateral branch, and atrioventricular branch were revascularized with the RITA. Post operative course was uneventful. Internal thoracic artery (ITA) is superior to vein graft and other arterial graft as to long term patency. We believe composite Y graft with the use of bilateral ITA can be one of the revascularization strategy in redo CABG.     

Role of radial artery graft in coronary artery bypass grafting

The use of the radial artery (RA) as a coronary artery bypass graft has assumed a revival and thus a multitude of issues have arisen surrounding the routine and widespread use of this conduit in myocardial revascularization. There has been no uniformity regarding harvest techniques, assessment of the adequacy of hand collateral circulation, antispasm protocols, selection of target vessels, and the site of proximal anastomosis. It is widely believed and practiced that the RA should be harvested as a pedicle graft and preferably be used to bypass critically stenosed (>70% stenosis) coronary arteries. It is used either as a free graft with proximal anastomosis to the ascending aorta or as a composite arterial graft along with the left or right internal thoracic artery. The patency of RA grafts depends on the severity of the target coronary artery stenosis and target artery location rather than its use as an aortocoronary conduit or composite graft. In this article, we reviewed the current knowledge regarding the use of RA grafts as a coronary bypass conduit in an attempt to suggest a few acceptable strategies concerning the above issues in a given clinical scenario.     

Arterial grafts in coronary bypass surgery.

During the last three decades, coronary artery bypass grafting (CABG) emerged, was developed and has progressed. The search for suitable conduits has been investigated aggressively and several venous, arterial and artificial grafts have been utilized clinically. It is clear now that the saphenous vein graft deteriorates with time and the occlusion rate reaches up to 50% at 10 years after CABG mainly due to atherosclerosis in the graft called "vein graft disease." The internal thoracic artery (ITA) graft, on the contrary, has very good long-term patency and this evidence directly relates to the superior outcome in terms of longevity and postoperative cardiac events in the long run. Based on this evidence, the use of arterial conduits for myocardial revascularization has been extended. Several autologous arteries have been investigated and utilized clinically such as the right gastroepiploic artery, the inferior epigastric artery, and the radial artery. With proper use of these new arterial conduits in addition to ITA, higher quality CABG can be performed safely, and a better long-term result can be expected.     

The right gastroepiploic artery in coronary artery bypass grafting

The right gastroepiploic artery (RGEA) has been used as a conduit in coronary artery bypass grafting. Although some reports presenting good results justify its use in clinical settings, there is still much concern about using the RGEA in bypass surgery. The RGEA demonstrates different behaviors from the internal thoracic artery (ITA) in bypass surgery due to its histological characteristics and anatomical difference, which might contribute to the long-term outcome. Now that left ITA (LITA) to left anterior descending artery (LAD) is the gold standard, other grafts are expected to cover the rest of the coronary arteries. It should be elucidated how we can use other grafts and what we can expect from them. RGEA, as an arterial graft, can be used as an in situ graft or a free graft. The RGEA is mainly used to graft to the right coronary artery (RCA) because of its anatomical position, and its patency is not inferior to that of the saphenous vein (SVG). The RGEA can cover the lateral walls when its length is long enough or by making a composite graft with other grafts. However, when used to graft to the LAD, its mid-term patency is not favorable.     

Radial artery graft for coronary artery bypass surgery: biological characteristics and clinical outcome

The radial artery (RA) is gaining popularity as a bypass conduit for coronary artery bypass grafting, and its impact on clinical practice has been extensively explored. In the present article, we provide a review of postoperative hand circulation, vascular biological characteristics of the RA graft, the efficacy of vasodilator therapies, and mid-term clinical results of use of the RA graft. Fundamental studies revealed excellent vascular biological characteristics of the RA graft as a living arterial conduit, making it almost equivalent to the internal thoracic artery (ITA) graft. Clinical studies have yielded encouraging mid-term results. Most studies reported in favor of the RA graft over the saphenous vein graft with regard to patency rate, freedom from cardiac events, and survival. However, superiority of either the RA or right ITA graft has not been conclusively determined. The long-term results of RA grafts remain unknown, but at present, supplementary use of an RA graft with a left ITA graft appears feasible for CABG.     

The analysis for surgical procedures of coronary-artery bypass grafting: selection of graft materials]

We analyzed 222 patients undergoing coronary artery bypass grafting (CABG) in our institute. Our selection of graft materials consists of only one arterial conduit and one or more saphenous vein grafts (SVG). An arterial conduits (left internal thoracic artery (LITA) was mainly used for the left anterior descending coronary artery (LAD), while a SVG was used for coronary arterial branch. Our approach was evaluated by the mid-term prognosis as well as cardiac events. Seventy-one percent of patients with CABG could be followed. The graft patency rate was better for ITA grafts than for SVG (97.8% vs 88%). The incidence of late cardiac events was lower in patients with the LITA, to the LAD. Furthermore, these patients had a better survival rate at 4 years comparing with patients who had vein bypass grafts alone. We suggest that this selection of graft materials may be accepted in CABG for the good quality, avoiding the cardiac events.     

The radial artery in coronary surgery, 2018

It is now 25 years since the radial artery (RA) was reintroduced in coronary surgery. It has evolved into being a significant coronary artery bypass conduit and ranks third in usage after the internal thoracic artery (ITA) and saphenous vein grafts (SVG). Its advantages are that it can be readily and efficiently harvested, is of good length and appropriate size for coronary artery bypass graft (CABG) surgery, is robust and easy to handle, and remains free of atheroma, and there is minimal wound morbidity. The RA must be used judiciously with attention to spasm prophylaxis because of its muscular wall, and by avoiding competitive flow. Its patency is equivalent to the ITAs when placed to similar coronary territories and under similar conditions (stenosis, size, quality) and RA patencies are always superior to those of SVG in both observational and randomized studies—88–90% versus 50–60% at 10 years, and 80–87% versus 25–40% at 20 years. Its use and excellent patencies result in survival results equivalent to bilateral internal thoracic artery (BITA) grafting and always superior to left internal thoracic artery (LITA) +SVG. Typical radial artery multiarterial bypass grafting (RA-MABG) 10-year survivals are 80–90% versus 70–80% for LITA-SVG. In general, for every 100 patients undergoing CABG, 10 more patients will be alive at 10 years post-operatively. The RA also is important in achieving total arterial revascularization, and several reports indicate a further survival advantage for patients having three arterial grafts over two. The RAs are especially useful in diabetic, morbidly obese patients, those with conduit shortage, and leg pathology, and in coronary reoperations. Although the RA has equivalent patencies to the right internal thoracic artery (RITA), it is much more versatile. RAs that have been instrumented by angiography or percutaneous coronary intervention should be avoided. The radial artery has proved to be an excellent arterial conduit, is equivalent to but more versatile than the RITA, and is always superior to SVG. Its use should be part of every coronary surgeon’s skill set.     

Early and mid-term results of all arterial graft coronary artery bypass grafting using bilateral internal thoracic and radial arterial conduits

From March 1996 to May 2000, 41 patients [age 39-78 (mean 63.5 +/- 8.8) years, 90.2% male] underwent all arterial multiple coronary artery bypass grafting (CABG) using bilateral internal thoracic (BiITA) and radial (RA) arterial conduits. The reason for using RA was that the right gastroepiploic artery (RGEA) was small or occluded on preoperative angiography, a history of upper abdominal surgery or disease, or the right coronary arterial lesion was proximal and mild. The BiITA were used as in situ grafts and the proximal anastomosis of RA was to the ascending aorta in all cases. All patients underwent conventional elective CABG with median sternotomy using cardiopulmonary bypass. The mean number of anastomoses was 3.3 +/- 0.5 branches and complete revascularization rate was 80.5%. Postoperative follow-up averaged 20 months and the longest was 50 months. There was no early death, and overall graft patency 2-3 weeks after surgery was 96.2% (LITA 94.0%, RITA 97.6%, RA 97.6%). Four-year actuarial survival rate was 96.4 +/- 3.5% (1 patient: 9 months, no cardiac death), and cardiac event-free rate after surgery was 89.7 +/- 4.9% [4 patients: percutaneous transluminal coronary angioplasty (PTCA)]. However, once patients were discharged from hospital, cardiac event-free rate was 100%. These excellent results suggest that all arterial graft CABG was satisfactory, and RA can be used as a third suitable arterial bypass conduit, if RGEA cannot be used or is unsuitable for use.     

Midterm angiographic assessment of coronary artery bypass grafting without cardiopulmonary bypass

BACKGROUND: Coronary bypass surgery that provides good long-term graft patency can be performed on the beating heart as a viable alternative to conventional coronary artery bypass grafting (CABG). METHODS: From September 1993 to December 1996, 696 patients underwent CABG on the beating heart at the Ko?uyolu Heart and Research Hospital in Istanbul. Among them, 70 patients were chosen randomly for angiographic assessment of off-pump coronary artery bypass grafting. RESULTS: The interval from operation to angiography varied from 24 to 61 months (mean, 36.1+/-10.9 months). The patency rate of left internal mammary-left anterior descending artery anastomoses was 95.59% (patency achieved in 65 of 68 patients) and of vein grafts was 47.06% (patency achieved in 16 of 34 patients) (p < 0.0001). The patency rates of grafts anastomosed to the left anterior descending artery were significantly higher than the rates of the grafts anastomosed to the other coronary arteries (95.71% versus 45.45%, p < 0.0001). Multivariate analysis showed that graft type (p < 0.0001) and hyperlipidemia (p = 0.023) were significant predictors for graft occlusion. Left ventricular function improved significantly after CABG (p = 0.04). Reintervention (using percutaneous transluminal cardiac angioplasty) and reoperation rates were 0.97% and 1.4%, respectively. CONCLUSIONS: Off-pump coronary artery bypass grafting appears to produce midterm and long-term patency rates that are comparable to those of conventional techniques; that is especially true in cases of arterial conduits and of conduits anastomosed to the left anterior descending artery.     

Standard coronary artery bypass grafting and beating heart bypass. Indications and long-term results.

OBJECTIVES AND METHOD: We have performed 225 cases of coronary artery bypass grafting (CABG), between October 15 1995 and September 8 1999. We have evaluated the operative results of 121 cases (53.8%) of conventional CABG and 104 cases (46.2%) of minimally invasive coronary artery bypass grafting performed during this period. The average numbers of bypassed grafts was 3.45 for conventional CABG, and 1.41 for minimally invasive coronary artery bypass grafting. Sixty-seven right internal thoracic arteries, 145 left internal thoracic arteries, 71 gastroepiploic arteries, 38 radial arteries and 12 saphenous veins were used for conventional CABG, and 29 right internal thoracic arteries, 81 left internal thoracic arteries, 18 gastroepiploic arteries, 3 radial arteries, 10 saphenous veins and 2 inferior epigastric arteries were used for minimally invasive coronary artery bypass grafting. The total number of 303 grafts were anastomosed to 417 coronary arteries for conventional CABG, and 143 grafts were anastomosed to 147 coronary arteries for minimally invasive coronary artery bypass grafting. RESULTS: Although two saphenous veins were occluded, the early postoperative patency rate was 100% for conventional CABG using right internal thoracic arteries, left internal thoracic arteries, gastroepiploic arteries and radial arteries. Three site of stenosis in 18 left internal thoracic arteries and 2 in 16 right internal thoracic arteries were recognized in minimally invasive coronary artery bypass grafting without the use of stabilizers. One site of stenosis in 63 left internal thoracic arteries was recognized in minimally invasive coronary artery bypass grafting with the use of stabilizers. CONCLUSION: The use of stabilizers enables adaptation of the minimally invasive coronary artery bypass grafting procedure to a wider range of coronary artery bypass procedures, and a higher graft patency can be expected.     

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.     

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.     

The Shelhigh No-React bovine internal mammary artery: a questionable alternative conduit in coronary bypass surgery?

BACKGROUND: Increasing age and comorbidities among patients undergoing coronary artery bypass surgery (CABG) stimulates the exhaustive research for alternative grafts. No-React treatment should render the tissue resistant against degeneration and reduce early inflammatory response. The aim of the present study was an invasive assessment of the patency of No-React bovine internal mammary artery (NRIMA grafts) used as bypass conduit in CABG surgery. PATIENTS AND METHODS: Nineteen NRIMA grafts were used in 17 patients (2.9%) out of a total of 572 patients undergoing CABG surgery within a 12-month period. All intraoperative data were assessed and in-hospital outcome was analysed. Follow-up examination was performed 7.0+/-4.0 months after initial surgery, including clinical status and coronary angiography to assess patency of the NRIMA grafts. RESULTS: Average perioperative flow of all NRIMA grafts was 71+/-60 ml/min. One patient died in hospital due to a multi-organ failure. Four patients refused invasive assessment. Follow-up was complete in 12 patients with overall 13 NRIMA grafts. Nine NRIMA grafts (69.2%) were used for the right coronary system, two NRIMA grafts (15.4%) on the LAD and two on the circumflex artery. Graft patency was 23.1% and was independent of the intraoperative flow measurement. CONCLUSIONS: NRIMA grafts show a very low patency and cannot be recommended as coronary bypass graft conduits. Patency was independent of the perioperative flow, assessed by Doppler ultrasound. Because of this unsatisfying observation, this type of graft should be utilised as a last resource conduit and used only to revascularise less important target vessels, such as the end branches of the right coronary artery.     

Surgical revascularization of the myocardium

It has been 45 years ago when Longmire (1958.) used internal thoracic artery (ITA) for the first time in coronary artery bypass surgery (CABG). In this review, we are presenting novel surgical approaches in CABG surgery. We have also been summarized the best of knowledge, up to date, regarding histology, pharmacology and pathophysiology of conduits (VSM, ITA and alternative venous and arterial grafts) which have been used in CABG surgery, as well as factors influence on its short and long-term patency.     

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.     

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.