Postoperative radial artery angiography for coronary artery bypass surgery

The Use of Radial Artery for CABG: An Update

We used the radial artery as a second target conduit for coronary artery bypass grafting since 1971. However, randomized clinical studies have demonstrated differences in clinical outcomes between the radial artery and other grafts because these trials are underpowered. As we proceed toward 50 years of experience with radial artery grafting, we examined the literature to define the best second-best target vessel for coronary artery bypass grafting. The literature was reviewed with emphasis, and a large number of randomized controlled trials, propensity-matched observational series, and meta-analyses were identified with a large patient population who received arterial conduit and saphenous vein grafts. The radial artery has been shown to be effective and safe when used as a second target conduit for coronary artery bypass grafting. Results and patency rates were superior to those for saphenous vein grafting. It has also been shown that the radial artery is a safe and effective graft as a third conduit into the territory of the artery right coronary artery. However, there is little evidence based on a few comparable series limiting the use of the gastroepiploic artery. In its fifth decade of use, we can finally deduced that the aorto-to-coronary radial bypass graft is the conduit of choice for coronary operations after the left internal thoracic artery to the left anterior descending artery.

Patency of conduits in patients who received internal mammary artery, radial artery and saphenous vein grafts

Background

Where each patient has all three conduits of internal mammary artery (IMA), saphenous vein graft (SVG) and radial artery (RA), most confounders affecting comparison between conduits can be mitigated. Additionally, since SVG progressively fails over time, restricting patient angiography to the late period only can mitigate against early SVG patency that may have occluded in the late period.

Methods

Research protocol driven conventional angiography was performed for patients with at least one of each conduit of IMA, RA and SVG and a minimum of 7 years postoperative. The primary analysis was perfect patency and secondary analysis was overall patency including angiographic evidence of conduit lumen irregularity from conduit atheroma. Multivariable generalized linear mixed model (GLMM) was used. Patency excluded occluded or “string sign” conduits. Perfect patency was present in patent grafts if there was no lumen irregularity.

Results

Fifty patients underwent coronary angiography at overall duration postoperative 13.1 ± 2.9, and age 74.3 ± 7.0 years. Of 196 anastomoses, IMA 62, RA 77 and SVG 57. Most IMA were to the left anterior descending territory and most RA and SVG were to the circumflex and right coronary territories. Perfect patency RA 92.2% was not different to IMA 96.8%, P = 0.309; and both were significantly better than SVG 17.5%, P < 0.001. Patency RA 93.5% was also not different to IMA 96.8%, P = 0.169, and both arterial conduits were significantly higher than SVG 82.5%, P = 0.029. Grafting according to coronary territory was not significant for perfect patency, P = 0.997 and patency P = 0.289. Coronary stenosis predicted perfect patency for RA only, P = 0.030 and for patency, RA, P = 0.007, and SVG, P = 0.032.

When both arterial conduits were combined, perfect patency, P < 0.001, and patency, P = 0.017, were superior to SVG.

Conclusions

All but one patent internal mammary artery or radial artery grafts had perfect patency and had superior perfect patency and overall patency compared to saphenous vein grafts.

Comparison of Sharp Dissection, Electrocautery, and Ultrasonic Activated Scalpel with Regard to Endothelial Damage, Preparation Time, and Postoperative Bleeding During Radial Artery Harvesting

OBJECTIVE

To examine the effects of classical technique, electrocautery, and ultrasonic dissection on endothelial integrity, function, and preparation time for harvesting the radial artery (RA) during coronary artery bypass grafting (CABG).

METHODS

Forty-five patients who underwent isolated CABG and whose RA was suitable for use were studied and divided into three groups: Group 1, classical method (using sharp dissection); Group 2, electrocautery; and Group 3, ultrasonic cautery. Levels of prostacyclin and nitric oxide derivatives were examined biochemically; vascular cell adhesion molecule 1 (VCAM-1) and endothelial nitric oxide synthetase (eNOS) values were assessed using immunohistochemical staining. RA preparation time, RA length/harvesting time ratio, and drainage amounts at the site of RA removal were compared.

RESULTS

Differences in RA preparation time (Group 1: 25±6 min, Group 2: 18±3 min, Group 3: 16±3 min, P<0.001) and length/harvesting time ratio (Group 1: 0.76±0.19 cm/min, Group 2: 0.98±0.16 cm/min, Group 3: 1.13±0.09 cm/min, P<0.001) were statistically significant among the groups. Levels of prostacyclin and nitric oxide derivatives were not statistically significant different, VCAM-1 and eNOS expressions were observed to be similar among the groups, and endothelial damage was detected in only one patient per group.

CONCLUSION

Use of ultrasonic cautery during RA preparation considerably reduces the preparation time and postoperative drainage amount. However, the superiority of one method over the others could not be demonstrated when the presence of endothelial damage with both biochemical and histopathological evaluations was considered.

Patency When Grafted to Coronary Stenosis More Than 50% in LIMA-RA-Y Grafts

BACKGROUND

Recent coronary surgery practice is to graft arterial conduits to more severely stenosed coronary targets than in the past. We aimed to investigate postoperative arterial graft patency with native coronary stenosis at the time of surgery, using the left internal mammary artery and radial artery (RA) as a composite Y graft (LIMA-RA-Y). In the study timeframe, it was routine clinical practice to graft coronary arteries with >50% stenosis.

METHODS

Of 464 patients previously reported 1996-1999, 346 who underwent LIMA-RA-Y at the Royal Melbourne Hospital, 76 had postoperative angiograms at the same institution. Each anastomosis was considered separately. For arterial grafts a "string sign" was analysed as being occluded. Predictor of patency was performed with a generalised linear mixed model (GLMM).

RESULTS

Seventy-six (76) patients had postoperative angiograms at 5.8±5.4 years (range 0.23-19.4; interquartile range 1.7-10.0) years postoperative; with age at operation 62.5±10.7 years and 3.4±0.8 grafts per patient, 82% were male. Of 256 anastomoses, 230 were to coronary targets >50% stenosis. Overall patency was 84.0% (214/256). For coronary stenosis >50%, patency was 88% (201/230) and varied by coronary territory left anterior descending (LAD) 94% (87/93), circumflex 90% (71/79) and right coronary artery (RCA) 74% (43/58). Interaction for coronary territory was significant (p=0.022). Higher preoperative coronary stenosis predicted higher patency; with odds ratio for improved patency of 1.83 (95% CI 1.51, 2.22), p<0.001 for each 10% increase in stenosis.

CONCLUSIONS

Late patency of composite arterial grafts is acceptable when grafted to coronary arteries of greater than 50% stenosis.

The Risk Factor Analysis for the Late Graft Failure of Radial Artery Graft in Coronary Artery Bypass Grafting

Objective: The aim of this retrospective study was to investigate the early operative results and detect the factors influencing the fate of radial artery grafts (RAGs) by evaluating the mid-term patency.

Methods: We retrospectively reviewed 410 patients who underwent isolated coronary artery bypass grafting using RAG. RAGs were anastomosed to 526 coronary arteries. Mid-term angiography was performed in 214 patients at an average 4.9 years after the operation.

Results: The early patency of RAGs was 97.6%. Cumulative 5-year patency was 86.5% for RAG, 94.1% for LITA graft, and 81.0% for saphenous vein graft (SVG). RAG was significantly superior to SVG in mid-term patency. Individual grafting (not sequential grafting) (hazard ratio [HR]: 2.535; 95% confidence interval [CI]: 1.293–5.281; p = 0.006) and grafting to the target coronary artery with ≤75% proximal stenosis (HR: 1.947; 95% CI: 1.090–3.484; p = 0.025) were found to be independent risk factors influencing late RAG patency.

Conclusions: The patency of RAGs was superior to that of SVGs in the studied population. When using RAGs, grafting to the target vessel with severe proximal stenosis is favorable. The RAG is suitable for sequential grafting.

Comparison of graft patency following coronary artery bypass grafting in the left versus the right coronary artery systems: a systematic review and meta-analysis

Although coronary artery bypass grafting has been the standard of care for patients with complex coronary artery disease for over 50 years, the evolution of graft patency over time in the left versus the right coronary systems remains poorly documented. This systematic review and meta-analysis aimed to characterize the evolution of graft patency over time comparing the left (excluding left anterior descending artery) and right coronary systems, with an emphasis on the comparison of venous versus arterial grafts and symptomatic versus asymptomatic patients. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and MEDLINE from inception to August 2016. We also searched clinical trials registers and reference lists of relevant studies. We included randomized clinical trials and observational studies comparing graft patency in the left versus the right coronary systems. Our outcome was graft patency defined as a binary variable according to whether grafts were reported as patent or failed at the time of angiogram. Data collection and analysis were performed according to the methodological recommendations of the Cochrane Collaboration. From a total 2275 papers, 52 studies were included in the qualitative analysis and 48 studies (including 36 006 grafts) in the meta-analysis. There was a 3.3% significant difference between the left-sided and right-sided graft patency, and the difference appeared to increase over time. Furthermore, patency of arterial grafts was higher in the left coronary system, while venous grafts performed similarly irrespective of the coronary circulation. Symptom recurrence also seemed related to a higher failure rate in the right coronary circulation. However, the high degree of heterogeneity precluded drawing definite conclusions. This meta-analysis suggested that graft patency might be better for left-sided vessels and that this difference might be driven by the better performance of arterial grafts in the left coronary system. However, evidence currently available is limited, and further research is warranted to understand whether certain grafts achieve better patency in the right versus the left coronary circulations.

Should functional assessment of lesion severity be used to guide coronary bypass?

PURPOSE OF REVIEW

The purpose of this article is to investigate the potential role of fractional flow reserve (FFR) to guide surgical revascularization.

RECENT FINDINGS

Coronary artery bypass is planned and executed primarily based on angiographic coronary anatomy. FFR is the most well-established tool for functional assessment of coronary lesions. Randomized trials have demonstrated the benefit of FFR-guided percutaneous coronary intervention (PCI) to determine the ischemic burden of intermediate lesions. Surgically, FFR is predominantly used to determine the functional severity of intermediate lesions of the left anterior descending (LAD) coronary artery to establish candidacy for multivessel coronary bypass. The broader use of FFR will likely downgrade a proportion of coronary lesions, which may alter the overall management plan. Whether this will improve clinical outcomes remains to be seen. Importantly, bypass of functionally nonsignificant lesions predicts graft failure. However, graft failure in the context of sufficient native coronary flow may not impact negatively on clinical outcome. Thus, at this time, there are insufficient data to support the wider use of FFR to guide surgical grafting of non-LAD targets. It remains to be seen whether FFR can be used to optimize the use of arterial grafts or to guide complex revascularization strategies such as hybrid coronary revascularization.

SUMMARY

FFR has become an invaluable tool for decision making for PCI in patients with stable ischemic heart disease. Beyond its use to assess an intermediate LAD lesion to establish candidacy for coronary bypass, at present there are insufficient data to support its wider use to guide surgical revascularization.

A mechanical argument for the differential performance of coronary artery grafts

Coronary artery bypass grafting (CABG) acutely disturbs the homeostatic state of the transplanted vessel making retention of graft patency dependent on chronic remodeling processes. The time course and extent to which remodeling restores vessel homeostasis will depend, in part, on the nature and magnitude of the mechanical disturbances induced upon transplantation. In this investigation, biaxial mechanical testing and histology were performed on the porcine left anterior descending artery (LAD) and analogs of common autografts, including the internal thoracic artery (ITA), radial artery (RA), great saphenous vein (GSV) and lateral saphenous vein (LSV). Experimental data were used to quantify the parameters of a structure-based constitutive model enabling prediction of the acute vessel mechanical response pre-transplantation and under coronary loading conditions. A novel metric Ξ was developed to quantify mechanical differences between each graft vessel in situ and the LAD in situ, while a second metric Ω compares the graft vessels in situ to their state under coronary loading. The relative values of these metrics among candidate autograft sources are consistent with vessel-specific variations in CABG clinical success rates with the ITA as the superior and GSV the inferior graft choices based on mechanical performance. This approach can be used to evaluate other candidate tissues for grafting or to aid in the development of synthetic and tissue engineered alternatives.

Endoscopic versus open radial artery harvest and mammario-radial versus aorto-radial grafting in patients undergoing coronary artery bypass surgery: protocol for the 2 × 2 factorial designed randomised NEO trial

Background

Coronary artery bypass grafting using the radial artery has, since the 1990s, gone through a revival. Observational studies have indicated better long-term patency when using radial arteries. Therefore, radial artery might be preferred especially in younger patients where long time patency is important. During the last 10 years different endoscopic techniques to harvest the radial artery have evolved. Endoscopic radial artery harvest only requires a small incision near the wrist in contrast to open harvest, which requires an incision from the elbow to the wrist. However, it is unknown whether the endoscopic technique results in fewer complications or a graft patency comparable to open harvest. When the radial artery has been harvested, there are two ways to use the radial artery as a graft. One way is sewing it onto the aorta and another is sewing it onto the mammary artery. It is unknown which technique is the superior revascularisation technique.

Methods/Design

The NEO Trial is a randomised clinical trial with a 2 × 2 factorial design. We plan to randomise 300 participants into four intervention groups: (1) mammario-radial endoscopic group; (2) aorto-radial endoscopic group; (3) mammario-radial open surgery group; and (4) aorto-radial open surgery group.

The hand function will be assessed by a questionnaire, a clinical examination, the change in cutaneous sensibility, and the measurement of both sensory and motor nerve conduction velocity at 3 months postoperatively. All the postoperative complications will be registered, and we will evaluate muscular function, scar appearance, vascular supply to the hand, and the graft patency including the patency of the central radial artery anastomosis. A patency evaluation by multi-slice computer tomography will be done at one year postoperatively.

We expect the nerve conduction studies and the standardised neurological examinations to be able to discriminate differences in hand function comparing endoscopic to open harvest of the radial artery. The trial also aims to show if there is any patency difference between mammario-radial compared to aorto-radial revascularisation techniques but this objective is exploratory.

Trial registration

ClinicalTrials.gov identifier: NCT01848886.

Danish Ethics committee number: H-3-2012-116.

Danish Data Protection Agency: 2007-58-0015/jr.n:30–0838.

Radial artery as graft for coronary artery bypass surgery: Advantages and disadvantages for its usage focused on structural and biological characteristics

Radial artery (RA) is the most popular arterial graft after the left internal thoracic artery in both low- and high-risk patients undergoing coronary artery bypass grafting. Various arterial grafts such as the right internal thoracic artery, the right gastroepiploic artery, and the inferior epigastric artery have also gained ground over the past 30 years because of the intimal hyperplasia and atherosclerosis of the saphenous vein leading to late graft occlusion. In this review article we would like to present the utility of the RA as a graft, focused mainly on its structural and biological characteristics.

Composite arterial grafting

The success of coronary artery bypass grafting, the gold standard for the treatment of multivessel coronary artery disease, is limited by poor long-term vein-graft patency. By contrast, the left internal mammary artery has been demonstrated to have a superior graft patency rate and has provided excellent clinical results. This suggests that the use of arterial conduits for coronary artery bypass grafting may be beneficial for long-term results. Recently, there has been an upsurge in the use of arterial grafts for myocardial revascularization based on the clinical advantage of the use of the left internal mammary artery as a bypass conduit. Many retrospective studies have supported the safety and the effectiveness of arterial grafting, and it has become apparent that the free arterial graft can be used as a branched or a lengthened conduit to the in situ arterial graft by adopting one or more of the several composite grafting techniques. Arterial composite grafts with or without sequential grafting techniques appear an attractive strategy as increased number of distal coronary anastomoses can be performed, with a limited number of grafts, avoiding proximal aortic anastomoses. However, concerns regarding the total dependence of the coronary bypass flow on the flow of one in situ arterial graft and technical error, resulting in compromised flow in one or both limbs of the composite graft have prevented composite arterial grafting from being universally adopted. It is expected that in the near future a prospective, multi-institutional, randomized controlled trial, to compare the short- and long-term outcomes of exclusive arterial grafting using composite and conventional aortocoronary revascularization strategies, will be undertaken to validate the safety and efficacy of composite arterial grafting.

Endoscopic radial artery harvesting procedure for coronary artery bypass grafting

Development and adoption of endoscopic minimally invasive saphenous vein harvesting prompted its application to the radial artery in an effort to minimize surgical trauma. Recently, we reported that endoscopic radial artery harvesting was associated with better wound appearance and it proved to be safe and effective, with less pain and fewer wound complications than the open surgical technique. Based on this positive experience, our institution adopted endoscopic radial artery harvesting, hence the aim of this manuscript is to describe the minimally invasive endoscopic radial artery harvesting for coronary artery bypass grafting.

Angiographic outcomes of radial artery versus saphenous vein in coronary artery bypass graft surgery: a meta-analysis of randomized controlled trials

INTRODUCTION

The efficacy of coronary artery bypass graft (CABG) surgery for patients with ischemic heart disease is dependent on the patency of the selected conduit. The left internal thoracic artery is considered to be the best conduit for CABG. However, the preferred conduit between the radial artery (RA) and saphenous vein (SV) remains controversial. The present meta-analysis aims to establish the current level IA evidence on patency outcomes comparing the RA and SV.

METHODS

Electronic searches were performed using 6 databases from their inception to March 2012. Two reviewers independently identified all relevant randomized controlled trials (RCTs) comparing patency outcomes of RA and SV grafts after CABG. Data were extracted and meta-analyzed according to angiographic end points at specified follow-up intervals.

RESULTS

Five relevant RCTs were identified for inclusion in the present meta-analysis. Angiographic results indicated that the RA was significantly more likely to be completely patent and less likely to be associated with graft failure or complete occlusion at 4 years' follow-up and beyond. However, the RA was significantly more likely to be associated with string sign at 1 year of follow-up.

CONCLUSIONS

While acknowledging the limitations of heterogeneous surgical techniques, results from the present meta-analysis suggest potential superiority of the RA compared with the SV at midterm angiographic follow-up. However, the increased incidence of string sign associated with the RA is of potential clinical concern. Further research should be directed at correlating angiographic findings of string sign and graft failure to clinical symptoms and major adverse cardiac and cerebrovascular events at long-term follow-up.

Endoscopic versus open radial artery harvesting for coronary artery bypass grafting

BACKGROUND AND AIM OF THE STUDY

The radial artery has become the artery of choice after both internal thoracic arteries for coronary artery bypass grafting (CABG). This study compares wound healing and arm complications after endoscopic versus open radial artery harvesting.

METHODS

From January 2002 to July 2004, 509 patients underwent CABG including a radial artery conduit. Thirty-nine had endoscopic and 470 conventional open radial artery harvesting. A propensity score was used to obtain 1:3 matching of all endoscopic to 117 open-harvesting patients. Postoperative wound healing, local neurologic deficits, wound infection, and pain scores were compared.

RESULTS

Wound healing: 34 of 39 endoscopic wounds exhibited a perfect Hollander score versus 339 of 470 open-harvest wounds (p = 0.01). Wound appearance was better for endoscopic harvesting (p = 0.004). Three incomplete neurologic deficits were observed after open harvesting versus one complete neurologic deficit after endoscopic harvesting that recovered prior to hospital discharge. Incidence of wound infection was similar in both groups (p = 0.7), although infection was more severe with open harvesting. Pain score was lower (p = 0.006) with endoscopic harvesting.

CONCLUSIONS

Endoscopic radial artery harvesting was associated with better wound appearance and less pain. Occurrence of neurologic deficits and wound infection was infrequent in both groups.

Late improvement in graft patency after coronary artery bypass grafting: Serial assessment with multidetector computed tomography in the early and late postoperative settings

OBJECTIVE

Grafts initially showing poor patency after coronary artery bypass grafting have occasionally shown improvement on serial multidetector computed tomography. This study analyzed possible factors associated with this phenomenon.

METHODS

Between September 2003 and July 2007, 512 patients underwent multidetector computed tomography within 1 month of isolated coronary artery bypass grafting. Among them, 1720 distal anastomoses were made with 1042 arterial and 302 venous conduits. Of these, 95 grafts (in 73 patients) were faint (n = 67) or nonvisualized (n = 28). Seventy-three of these grafts (in 56 patients) had follow-up multidetector computed tomographic evaluation 1 year after surgery and comprised the study group.

RESULTS

Improvement in graft patency (faint to patent or nonvisualization to visualization) occurred in 44 grafts (60.3%). Multivariate analysis revealed proximal target vessel stenosis of at least 90% (relative risk, 3.81; P = .009), larger target coronary size (relative risk, 1.72; P = .002), and radial artery graft use (relative risk, 4.44; P = .003) to be significantly associated with the graft patency restoration. Graft patency restoration was most commonly observed in a group of 28 radial artery grafts that were anastomosed to target vessel with proximal stenosis of at least 90%; of these grafts, 24 (85.7%) showed improved graft patency on follow-up.

CONCLUSIONS

A large proportion of radial artery grafts initially showing poor opacification after coronary artery bypass grafting demonstrated patency restoration on serial multidetector computed tomography. Larger target vessel size and target vessel stenosis of at least 90% were significant correlative factors.

Radial artery graft flowmetry is better than saphenous vein on postero-lateral wall

BACKGROUND

Although general agreement exists on internal mammary graft as the first conduit, the second choice is still questioned. Despite radial artery (RA) grafting has been suggested, saphenous veins (SV) continue to be extensively used.

METHODS

A prospective series of isolated RA-CABG (150 patients) or SV-CABG (180 patients), performed either off-pump (OP-CABG) and on-pump (CPB-CABG), in diabetics and non-diabetics, in elderly and young patients, during the last 5-years at a single institution were evaluated. RA was harvested with harmonic scalpel, flowmetry was performed with a transit-time flowmeter (TTF). Graft flow reserve (GFR) was calculated with intra-aortic balloon-pump. Follow-up was collected by outpatient clinic database or by telephone interview with general practitioners.

RESULTS

The 2 groups showed comparable preoperative and intraoperative variables. Mortality, morbidity, myocardial infarction, troponin I leakage, and echocardiographic parameters were comparable (p=NS). RA-CABG demonstrated significantly higher TTF maximum, mean and minimum flow (p<.001) with lower Pulsatility Index (p<.001), either in the circumflex and the right coronaries. Compared to SVG-grafting, significantly higher GFR was found in RA-CABG on the circumflex (p=.001) and right (p=.028) coronaries. 38.1+/-0.9 SE months follow-up resulted in higher survival and freedom from cardiac events in RA-CABG. Better TTF and GFR were demonstrated in OP-CABG, CPB-CABG, diabetics, non-diabetics, either on the circumflex and right coronary systems (p<.05). Better mean flow was detected in RA-CABG on the circumflex in the elderly (p=.04) and the young (p=.05).

CONCLUSIONS

RA-CABG demonstrated better TTF and GFR results compared to SV-CABG. These data may contribute to explain the survival benefit of arterial revascularization already reported.

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.

Predictive factors for the intermediate-term patency of arterial grafts in aorta no-touch off-pump coronary revascularization

OBJECTIVE

Graft flow is one of the important determinants of the arterial graft patency. To establish the optimal graft design, we examined detailed characteristics of the arterial composite and sequential grafts, and sought to delineate the risk factors of graft occlusion due to insufficient bypass flow.

METHODS

Angiograms of 2547 bypass grafts in 677 consecutive patients who underwent total arterial off-pump CABG without aortic manipulation followed by early postoperative angiography since December 2000 were reviewed. The angiographic flow was graded as A (antegrade), B (competitive), C (reversal), and O (occlusion).

RESULTS

The overall early graft patency rate was 98.2% (2502/2547). The rate of grade A was 91.3% (2325/2547), while the rates of grades B and C were 2.9% (73/2547) and 4.1% (104/2547), respectively. For the main trunk of the anterior descending branch (LAD), the graft patency rate was 99.3% (674/679). The grade A rate of the internal thoracic artery (ITA) grafts to LAD in an individual fashion was 99.5% (203/204), being comparable with that in the sequential or composite grafting which had two distal anastomoses (98.1%, 159/162; p=0.33). The actuarial patency rates at 3 years were 84.7% for the bypass grafts with grade A flow and 33.9% for those with grade B/C flow, respectively (p<0.0001). The multivariate Cox-regression analysis demonstrated that grade B/C (p<0.0001, HR=4.19) and 51-75% stenosis of the native coronary artery (p=0.02, HR=2.86) were significant predictors of graft occlusion.

CONCLUSIONS

For the LAD, the results of graft flow in sequential ITA grafting or composite grafting with two distal anastomoses were comparable with that in individual ITA grafting. Prediction and prevention of competitive and reverse flow are mandatory for achieving the advantages of the arterial materials.

Patency rates of endoscopically harvested radial arteries one year after coronary artery bypass grafting

OBJECTIVES

To improve patients' acceptance of the radial artery as a graft for coronary revascularization, we introduced an endoscopic harvesting technique. The aim of this study was to assess graft quality 1 year after the operation.

METHODS

In 50 patients who underwent endoscopic radial artery harvesting for coronary artery bypass grafting, 64-slice computed tomography, electrocardiography, and echocardiography were utilized to assess graft patency and left ventricle function at a 1-year follow-up. In addition, the influencing factors of radial artery graft patency were evaluated. Radial artery patency was compared with a control group from our database.

RESULTS

Any patency of endoscopically harvested radial artery grafts was 78% (39/50) and perfect patency was 72% (36/50) 1 year after coronary revascularization. The implanting surgeon and graft harvester, patient factors, graft properties, medication, and target territory did not influence the patency rates of the radial artery graft. The only significant and strong parameter to predict perfect graft patency was the severity of the target vessel stenosis (P < .001). In patients with a target vessel stenosis of 90% or greater, radial artery graft patency was 90.3% (28/31). Patency rates of endoscopically (72%) and conventionally (74%) harvested radial arteries were not different (P = .822).

CONCLUSIONS

Patency rates 1 year after endoscopic radial artery harvesting are comparable to the open technique. On the basis of our results, we attempt to use the radial artery as a bypass graft only for target coronary arteries with 90% or greater stenosis. We recommend endoscopic harvesting as the technique of choice to harvest the radial artery.

Midterm follow-up of patients receiving radial artery as coronary artery bypass grafts using 16-detector-row CT coronary angiography

PURPOSE

The study was undertaken to evaluate the 3-year outcome of patients undergoing coronary artery bypass grafting (CABG) involving the use of the radial artery (RA) in comparison with the left internal mammary artery (LIMA) and saphenous vein (SV) grafts by using 16-slice multidetector computed tomography (MDCT).

MATERIALS AND METHODS

Fifty-one patients underwent electrocardiogram (ECG)-gated 16-MDCT 32+/-4 months after surgery. A total of 50 LIMA grafts, 55 SV grafts and 51 RA grafts were studied. Approximately 68.6% or RAs were free, 21.5% sequential and 9.8% composite. Grade 0 was defined as complete patency, grade 1 as focal stenosis (>70%) and grade 2 as graft occlusion. The Fisher exact test was used to analyse variables (p<0.05 significant). Concordance between readers for the detection of patency was calculated by the kappa-value.

RESULTS

LIMA had the best patency rate (94.0%), followed by SV (83.6%) and RA (74.5%). Regarding RA, the patency rate by territory was 79.4% in the left circumflex coronary artery (LCX), 72.7% in the left anterior descending (LAD) and 50% in the right coronary artery (RCA); the occlusion rate was 20.0% among free grafts, 18.2% among sequential grafts and 20.0% among composite grafts. The kappa-value was 0.86.

CONCLUSIONS

Sixteen-slice MDCT scanners enable accurate analysis of CABG status and are a useful noninvasive diagnostic tool for midterm clinical follow-up of patients who have undergone CABG involving the use of RA.

Pre-emptive stellate ganglion block increases the patency of radial artery grafts in coronary artery bypass surgery

BACKGROUND

We evaluated the role of pre-emptive stellate ganglion block (SGB) in preventing radial artery spasm and increasing radial artery graft patency in patients undergoing off-pump coronary artery bypass surgery.

METHODS

In this prospective randomized study, 100 patients were divided into two equal groups (n= 50). In group A, SGB was achieved using 10 ml of ropivacaine and, in group B, SGB was not performed. Radial artery blood flow was measured pre- and intra-operatively. Post-operative clinical determinants (S-T segment elevation, use of inotropic agents, incidence of atrial fibrillation) were recorded. Early coronary angiography was performed.

RESULTS

According to blood flowmeter measurements, the radial artery blood flow was significantly increased in patients with SGB. The incidence of atrial fibrillation, the need for inotropic agents and S-T segment elevation were all decreased in the SGB group. Angiographic intervention revealed that the incidence of graft spasm was also lower in the SGB group.

CONCLUSION

Pre-emptive SGB is an effective method for increasing radial artery blood flow and preventing radial artery spasm. Complications related to radial artery spasm may be decreased and patients may have a more comfortable post-operative period with this method.

Endoscopic Radial Artery Harvesting may be the Procedure of Choice for Coronary Artery Bypass Grafting

BACKGROUND

This study assessed the neurologic and cosmetic outcome of the endoscopic radial artery harvesting (ERH) technique in coronary artery bypass grafting (CABG).

METHODS AND RESULTS

The study group comprised 257 consecutive patients who underwent CABG between January 2001 and August 2005 at Kyungpook National University Hospital. The first 157 patients (open group) underwent conventional open harvesting of the radial artery and the second 100 (endoscopic group) had endoscopic harvesting. The severity of both the motor and sensory symptoms, as well as the cosmetic results, was evaluated immediately and at least 6 months after surgery. In the open group, 29 patients experienced neuralgia along the distribution of the lateral antebrachial cutaneous nerve, but none in the endoscopic group patients experienced any sensory abnormalities (p<0.05). However, neuralgia along the distribution of the superficial radial nerve was similarly observed in both groups. No one in either group complained of any motor symptoms. The patients in the endoscopic group were also satisfied with the cosmetic results.

CONCLUSIONS

ERH resulted in less neurologic complications of the hand and forearm, and outstanding aesthetics. ERH may be the procedure of choice for radial artery harvesting.

Skeletonized harvesting improves the early-term and mid-term perfect patency of a radial artery graft

OBJECTIVE

A radial artery (RA) graft is frequently used for coronary artery bypass grafting (CABG), but little information exists regarding the early- and mid-term patency associated with the harvesting procedure. The objective of this study is to compare the early- and mid-term patency of the RA graft obtained using non-skeletonized and skeletonized harvesting.

METHODS

Altogether, 131 patients and 159 anastomoses were studied. In 85 patients the RA was harvested non-skeletonized (group A: procedures between September 2000 and November 2002), whereas in 46 patients the RA was harvested skeletonized (group B: procedures between November 2002 and April 2004). Angiography results were analyzed before discharge [A: postoperative day (POD) 14.7 +/- 2.9, 75 patients, 90 anastomoses; B: POD 13.7 +/- 1.9, 38 patients, 47 anastomoses], and after 1 year (A: POD 386.8 +/- 149.3, 44 patients, 51 anastomoses; B: POD 267.1 +/- 148.7, 11 patients, 13 anastomoses).

RESULTS

There was no difference in patency between the two groups (group A vs group B, 96.7% vs 100%, P = not significant [NS], in the early-term, 96.2% vs 100%, P = NS, in the mid-term). However, the perfect patency rates for groups A and B were 86.7% and 98.1%, respectively, in the early-term (P = 0.034) and 77.5% and 100%, respectively, in the mid-term (P = 0.048). The location and severity of the target vessel did not influence the angiographic results.

CONCLUSION

The early- and mid-term patency of RA grafts was excellent, and skeletonized harvesting improved the perfect patency rates at both time points.

Angiographic flow grading and graft arrangement of arterial conduits

OBJECTIVE

We sought to delineate the effects of competitive and reverse flow on the intermediate-term patency of arterial conduits and examined graft arrangements for maximizing antegrade bypass flow.

METHODS

The angiograms of 2083 bypass grafts in 570 patients who underwent off-pump total arterial revascularization without aortic manipulation since December 2000 were reviewed. The blood flow in the bypass grafts were graded A (antegrade), B (competitive), C (reverse), or O (occlusion). The mean number of distal anastomoses was 3.65 +/- 0.94 per patient.

RESULTS

In the early angiography 91.3% (1901/2083) of the bypasses were grade A. Thirty (1.4%) bypasses were grade O, whereas 2.9% (61/2083) were grade B, and 4.4%(91/2083) were grade C. In the multivariate analysis the end-to-side anastomosis (P < .0001), 4 or more distal anastomoses of the conduit (P = .01), native coronary stenosis of less than 75% (P < .0001), and target branch location of the right coronary artery territory (P < .0001) and left circumflex artery territory (P = .02) significantly correlated with grade non-A. The patency rate in the late angiography of the bypasses graded B or C in the early angiography was 7 (28.0%) of 25, whereas that of the bypasses graded A was 164 (89.1%) of 184 (P < .0001). The actuarial graft patency rate of the bypasses graded A was 72.3% at 3 years and was significantly higher than that of the bypasses graded B or C (28.6% at 3 years after surgical intervention, P < .0001).

CONCLUSIONS

The sufficient antegrade bypass flow had a favorable effect on the graft patency of arterial conduits. The graft arrangement should be adjusted for each patient so as to maximize the antegrade bypass flow and to confirm the advantage of arterial grafts.

Noninvasive Midterm Follow-Up of Radial Artery Bypass Grafts With 16-Slice Computed Tomography

BACKGROUND

The standard invasive procedure to evaluate graft patency is selective coronary angiography. The recent introduction of a new generation of multidetector row computed tomography made possible the noninvasive study of grafts with excellent results in terms of visualization and resolution. We used computed tomography to study all patients with a radial artery graft operated on in 2002.

METHODS

Between April and October 2005, we reviewed all patients operated on by coronary artery bypass grafting at our institution between January and December 2002. A total of 62 patients received a radial artery graft. Of these, 22 were lost at the time of follow-up. The other 40 patients were enrolled for a multidetector row computed tomography study. Demographic and instrumental data were collected for all the patients. A total number of 145 grafts were studied, with complete and excellent visualization.

RESULTS

The scans revealed a 97.77% (44 of 45) patency rate for left internal mammary arteries, 90.57% (48 of 53) for vein grafts, and 73.91% (34 of 46) for radial arteries (mammary artery plus vein grafts versus radial artery patency, p < 0.001). If analyzed for target vessel, we found the poorest result of radial grafts when placed on the right coronary artery (40% [2 of 5] patency rate).

CONCLUSIONS

Noninvasive control of previously bypassed patients is feasible, with no discomfort for them and excellent visualization of grafts. The use of the radial artery as a conduit for bypass graft can be achieved with good results, after a careful choice of the target vessel.

[Arterial grafts in coronary surgery for diabetic patients]

Surgical revascularization allows especially for the diabetic patient with coronary multi-vessel disease a superior long-termperspective compared to percutaneous coronary interventions. However, the specific advantages and also risks associated with the expanded use of arterial grafts as coronary conduits in diabetics are not clearly answered. A systemic analysis of the current literature underlines the following statements: The radial artery is, compared to the internal mammary artery, to a higher extent prone to atherosclerosis, especially in diabetic patients. Better long-term survival for patients with bilateral IMA-grafts has also been assessed for diabetic patients. The risk of thoracic wound infections is not obligatory increased for diabetics with double IMA-grafts. Revascularization with radial arteries can be performed with low perioperative risks. Long-term results or studies on radial artery bypass grafting especially in diabetics are not available. In our own experience (3,548 isolated coronary operations, 01/2001 until 05/2005), diabetic patients have no increased perioperative mortality, even when using more complex arterial grafting. Conclusively, diabetic patients should also significantly benefit from the use of the second mammary artery. Regarding conduit quality, a second IMA appears favorable over the radial artery.

Early outcome of a randomized comparison of off-pump and on-pump multiple arterial coronary revascularization

BACKGROUND

Previous randomized comparisons of off-pump and on-pump coronary artery bypass grafting (CABG) have yielded controversial results about the cardiac and neurological events and graft patency. In addition, these randomized studies were composed of CABG with a few arterial grafts. We performed a prospective randomized controlled study to compare off-pump and on-pump CABG with multiple arterial grafts.

METHODS AND RESULTS

Between July, 2002, and September, 2004, 167 consecutive unselected patients referred for elective primary CABG were randomly assigned to undergo multiple arterial off-pump CABG (n=81) or on-pump CABG (n=86). The clinical outcomes and S-100 protein, neuron-specific enolase, and maximum creatine kinase-MB levels were compared. Early graft patency was examined within 3 weeks after the operation by angiography. The number of grafts performed per patient (3.5+/-1.0 for off-pump CABG and 3.6+/-0.9 for on-pump CABG) and the number of arterial grafts performed per patient (3.3+/-1.0 for off-pump CABG and 3.4+/-0.9 for on-pump CABG) were similar. Completeness of revascularization (completed grafts/planned grafts) was 98% in both procedures. There were no hospital deaths in either group. The operation time was significantly (P<0.001) shorter in the off-pump group than in the on-pump group (267+/-60 minutes versus 307+/-59 minutes). The incidence of perioperative complications was similar. The frequency of no need for transfusion was higher in the off-pump group than in the on-pump group (80% versus 55%, P<0.001). The S-100 protein levels at the admission into the intensive care unit were significantly (P<0.001) lower in the off-pump group than in the on-pump group (0.20+/-0.11 ng/mL versus 0.34+/-0.22 ng/mL). The neuron-specific enolase levels at the intensive care unit admission were significantly (P<0.001) lower in the off-pump group than in the on-pump group (10.4+/-9.0 ng/mL versus 16.9+/-6.9 ng/mL). Maximum creatine kinase-MB levels were significantly (P=0.046) lower in the off-pump group than in the on-pump group (17.1+/-16.7 IU/L versus 21.5+/-10.6 IU/L). The overall early graft patency rate with or without stenosis was the same (98%) in both groups, but the rate without stenosis was slightly worse in the off-pump group (93%) than in the on-pump group (96%) (P=0.093). The stenosis-free patency rate in the right coronary area was significantly (P=0.028) worse in the off-pump CABG group (90%) than in the on-pump group (99%).

CONCLUSIONS

Off-pump CABG with multiple arterial grafts was as safe as the conventional on-pump CABG, with similar completeness of revascularization and early graft patency.

Extrafascially harvested radial artery in CABG: technique of harvest, complications, and mid-term angiographic patency

BACKGROUND

The initial use of radial artery (RA) for myocardial revascularization was abandoned due to high incidence of early occlusion. The revival of radial artery graft use was attributable to the improved harvesting techniques as well as the introduction of antispasm prophylaxis by calcium channel blockers. Various techniques of harvesting RA have been described and extrafascial harvest is one of the techniques to minimize trauma during harvest. The immediate arm complications and mid-term angiographic patency of the radial artery grafts harvested using extrafascial no-touch technique and used as a conduit for myocardial revascularization were not documented well in the literature.

METHODS

Between January 1997 and February 2003, 385 patients were operated for coronary artery bypass grafting using radial artery graft as one of the conduits. We used extrafascial no-touch technique and a coagulation current cautery at a strength of 10 to 15 W to control the bleeding during the blunt dissection of the radial artery. The complications related to the radial artery harvest were prospectively recorded and analyzed. This conduit was used as a free graft in 272 patients, left internal mammary artery and radial artery Y graft in 61 patients, Right internal mammary artery, and radial artery composite in situ graft in 52 patients. The radial artery donor arm in these patients was evaluated for complications. Angiographic evaluation of the radial artery graft was carried out randomly in 51 patients and angiography was done after an interval of 6 to 72 months (mean 29.55 +/- 21.77 months).

RESULTS

In two patients, although the preoperative Allen test was negative, the radial artery was not harvested after completion of the dissection and was left in situ because the pulse could not be felt in the radial artery distal to the clamp after trial occlusion of the mid part of RA. The arm complications noticed were cutaneous parasthesias in 9 patients (2.33%), which subsided in 4 weeks, stitch abscess and superficial wound infection in 4 patients (1.03%), hematoma/seroma treated with drainage in outpatient department in 3 patients (0.78%), and wound infection requiring open drainage in an operating room in one patient (0.76%). Angiographically radial artery was patent in 48 of 51 patients (94.11%).

CONCLUSIONS

The extrafascial technique of radial artery harvest is safe and an easily reproducible method with minimal arm complications and good mid-term clinical and angiographic results. The mid-term angiographic patency rates of RA harvested using this technique are comparable to that of the published results of intrafascially harvested radial artery grafts and left internal mammary artery grafts.

Radial Artery Angiographic String Sign: Clinical Consequences and the Role of Pharmacologic Therapy

BACKGROUND

The radial artery is an increasingly important graft for coronary artery bypass surgery. Postoperative angiographic studies have shown that a proportion of radial grafts become diffusely narrowed but not occluded, or string signs.

METHODS

Four hundred forty patients receiving a radial artery graft enrolled in a large clinical trial underwent postoperative angiography at 1 year. Angiograms were analyzed visually and quantitatively. A complete string sign was defined as diffuse narrowing along the full length of the graft, while a partial string sign was defined as segmental narrowing. Angiographic findings were correlated with medication compliance and clinical sequelae.

RESULTS

Thirty-one patients (7.0 %) had radial artery graft string signs versus 4 patients (0.9%) with a saphenous vein graft string sign (p = 0.001). Complete string signs were present in 28 cases, and the mean diameter was 0.76 +/- 0.14 mm (mean +/- SD), whereas 3 cases had a partial string sign with a diameter of 0.89 +/- 0.14 mm. Fifteen radial arteries showed Thrombolysis in Myocardial Infarction Study (TIMI) 1 flow, 3 cases showed TIMI 2 flow, and 13 cases showed TIMI 3 flow. There was no difference in incidence of radial string sign between patients taking nifedipine versus diltiazem postoperatively. Multivariate analysis revealed the presence of radial artery string sign was closely related to the perioperative use of alpha-adrenergic agonists and target vessels stenosis less than 90%. Postoperative symptoms were associated with radial artery string signs with TIMI 1 flow (p = 0.0045).

CONCLUSIONS

In the Radial Artery Patency Study, radial artery string sign was present in 7% of patients. Despite diffuse narrowing, 52% of grafts had TIMI 2 flow or better.

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.

Total Arterial Myocardial Revascularization Using Composite and Sequential Grafting With the Off-Pump Technique

BACKGROUND

Multiple arterial myocardial revascularizations are increasingly undertaken using off-pump techniques; however, various arterial grafting techniques are utilized. This study aimed to review the outcome of combining arterial composite and sequential grafting with off-pump techniques.

METHODS

We retrospectively reviewed the records of 107 consecutive patients who underwent coronary bypass surgery with off-pump and arterial composite grafting techniques between April 2001 and March 2004. The left internal thoracic artery (LITA) was harvested in all patients, and the right internal thoracic artery (RITA), the radial artery (RA), and the gastroepiploic artery (GEA) were harvested in 69 patients, in 83 patients, and in 53 patients, respectively. Early postoperative angiograms were evaluated in 97 patients.

RESULTS

There were 488 distal anastomoses, an average of 4.5 per patient. Forty-four in situ LITAs were used as LITA Y-composite grafts with a free RITA (n = 19), RA (n = 24), or free GEA (n = 1). Forty-three in situ RITAs were used as RITA-RA grafts (n = 42) or a RITA-GEA graft (n = 1). Twenty-one in situ GEAs were used as composite grafts with the RA (n = 17) or a free RITA (n = 4). There were no hospital deaths. The patency of the LITA was 100%, and that of the RA was 97.3%, while patencies of both in situ and free RITA and GEA were 100%. During the follow-up period (mean: 22.1 months), there were 3 late deaths, but none were cardiac related.

CONCLUSIONS

Total arterial revascularization with composite and sequential grafting is a safe and effective technique in patients undergoing off-pump coronary artery bypass surgery.

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.

Coronary revascularization with the left internal thoracic artery and radial artery: comparison of short-term clinical evolution between elective and emergency surgery

BACKGROUND

Left internal thoracic artery-to left anterior descending artery grafting has become a fundamental part of coronary artery bypass grafting. This grafting has led to increased use of other arterial conduits, of which the radial artery is most popular. Whether radial grafting can be used in the emergency patient is not known. This study compares the short-term clinical evolution between elective vs emergency coronary artery bypass grafting surgery with left internal thoracic artery and radial artery.

METHODS

A retrospective study of 47 patients who underwent elective or emergency coronary artery bypass grafting from 1996 to 2003. All patients had coronary stenosis>70% in all target vessels. Only the left internal thoracic artery and radial artery were used as grafts. Patients were divided into elective group (23 patients) and emergency group (24 patients). Emergency criteria were unstable angina and/or critical coronary stenosis with high risk for acute myocardial infarction. Groups were similar for age and number of diseased vessels.

RESULTS

The mean number of left internal thoracic artery grafts per patient in the elective and emergency groups were respectively 1.17 and 1.38 (P=.17). The mean number of radial artery grafts per patient in the elective and emergency groups was respectively 2.26 and 2.08 (P=.48). The 30-day mortality was 0. There was no postoperative cardiogenic shock. The elective group had 1 acute myocardial infarction (4.4%) postoperatively, and emergency group had 5 (20.8%). A nonsignificant trend towards acute myocardial infarction was noted in the emergency group (P=.18). Intensive care unit and postoperative stay were similar in both groups.

CONCLUSION

Coronary artery bypass grafting using left internal thoracic artery and radial artery accomplishing complete revascularization can be performed in emergency patients with results similar to those for elective patients.

Revascularization of the Right Coronary Artery: Grafting or Percutaneous Coronary Intervention?

BACKGROUND

The choice of myocardial revascularization strategy for the right coronary artery (RCA) in patients with multivessel disease and chronic stable angina remains controversial. Our aim was to determine the better strategy-hybrid, combining bypass of the left coronary network and percutaneous coronary intervention of the RCA, or exclusively surgical-and if the latter, the best conduit.

METHODS

We used decision analysis, a modeling technique, to compare two RCA revascularization strategies: surgical grafting and percutaneous coronary intervention. A review of the English language literature determined the variables for each strategy. All possible outcomes of each strategy were analyzed to determine the baseline strategy yielding the highest expected effectiveness. Sensitivity analysis determined the most relevant elements in the model and indicated threshold values.

RESULTS

Arterial grafting of the RCA led to the highest expected effectiveness, respectively 6% and 7% higher than that of percutaneous coronary intervention and the saphenous graft procedure. Of the arteries available-the radial, right gastroepiploic, and right internal thoracic artery-the most effective was the right internal thoracic artery, pedicled for the proximal part of the RCA and free connected as a Y or a T to the pedicled left internal thoracic artery for the distal part of the RCA. Sensitivity analysis showed surgery to be the appropriate strategy when the expected 1-year patency rate of the arterial graft exceeded 80%.

CONCLUSIONS

This analysis shows arterial grafting of the RCA to have better outcomes than percutaneous coronary intervention, and the right internal thoracic artery to be the best conduit.