Long-term results of the radial artery used for myocardial revascularization

From a Position of Known Angiographic Perfect Patency: What Happens Next?

BACKGROUND AND AIM

The biological behaviour of coronary graft conduits over time may be considered by serial angiography.

METHODS

A single institution retrospective cohort received mostly clinically indicated angiography between 1997 and 2020, following coronary bypass surgery. Only perfectly patent grafts (absence of any lumen irregularity) for each conduit type at the first postoperative angiogram were selected for a later comparison. The latest angiograms were at least 5 years postoperatively, and at least 1 year after first postoperative angiogram. Analysis was done according to each graft (anastomosis). Comparisons used generalised estimating equations, adjusted for binary logistic regression.

RESULTS

Of 143 patients, there were 410 of 468 (87.6%) perfectly patent grafts at the first angiogram, analysed at 6.8±4.0 years postoperative, of which 157 were internal mammary arteries, 228 were radial arteries, and 25 were saphenous veins. At the latest angiogram (12.2±3.8 years postoperative), comparison with the first angiogram for each individual graft found preserved perfect patency for internal mammary arteries, 156 of 157 (99.4%), and for radial arteries, 227 of 228 (99.6%) but saphenous veins deteriorated considerably, 13 of 25 (52.0%). The two arterial grafts (internal mammary and radial) were superior to vein grafts (odds ratio 163; 95% confidence interval [CI] 22-1,211; p<0.001), but not different from each other (odds ratio 0.95; 95% CI 0.78-1.16; p=0.584).

CONCLUSIONS

From a position of known angiographic perfect patency post-CABG, internal mammary artery and radial artery grafts retained their perfect patency in the longer term, but saphenous vein grafts did not.

Saphenous Vein Graft Failure: Current Challenges and a Review of the Contemporary Percutaneous Options for Management

The use of saphenous vein grafts (SVGs) in the surgical management of obstructive coronary artery disease remains high despite a growing understanding of their limitations in longevity. In contemporary practice, approximately 95% of patients receive one SVG in addition to a left internal mammary artery (LIMA) graft. The precise patency rates for SVGs vary widely in the literature, with estimates of up to 61% failure rate at greater than 10 years of follow-up. SVGs are known to progressively degenerate over time and, even if they remain patent, demonstrate marked accelerated atherosclerosis. Multiple studies have demonstrated a marked acceleration of atherosclerosis in bypassed native coronary arteries compared to non-bypassed arteries, which predisposes to a high number of native chronic total occlusions (CTOs) and subsequent procedural challenges when managing graft failure. Patients with failing SVGs frequently require revascularisation to previously grafted territories, with estimates of 13% of CABG patients requiring an additional revascularisation procedure within 10 years. Redo CABG confers a significantly higher risk of in-hospital mortality and, as such, percutaneous coronary intervention (PCI) has become the favoured strategy for revascularisation in SVG failure. Percutaneous treatment of a degenerative SVG provides unique challenges secondary to a tendency for frequent superimposed thrombi on critical graft stenoses, friable lesions with marked potential for distal embolization and subsequent no-reflow phenomena, and high rates of peri-procedural myocardial infarction (MI). Furthermore, the rates of restenosis within SVG stents are disproportionately higher than native vessel PCI despite the advances in drug-eluting stent (DES) technology. The alternative to SVG PCI in failed grafts is PCI to the native vessel, 'replacing' the grafts and restoring patency within the previously grafted coronary artery, with or without occluding the donor graft. This strategy has additional challenges to de novo coronary artery PCI, however, due to the high burden of complex atherosclerotic lesion morphology, extensive coronary calcification, and the high incidence of CTO. Large patient cohort studies have reported worse short- and long-term outcomes with SVG PCI compared to native vessel PCI. The PROCTOR trial is a large and randomised control trial aimed at assessing the superiority of native vessel PCI versus vein graft PCI in patients with prior CABG awaiting results. This review article will explore the complexities of SVG failure and assess the contemporary evidence in guiding optimum percutaneous interventional strategy.

Radial artery pulse wave velocity: a new characterization technique and the instabilities associated with the respiratory phase and breath-holding

Objective. Pulse wave velocity (PWV) is a key diagnostic parameter of the cardiovascular system's state. However, approaches aimed at PWV characterization often suffer from inevitable drawbacks. Statistical results demonstrating how closely PWV in the radial artery (RA) and the respiration phase correlate, as well as RA PWV evolution during breath-holding (BH), have not yet been presented in the literature. The aims of this study are (a) to propose a simple robust technique for measuring RA PWV, (b) to reveal the phase relation between the RA PWV and spontaneous breathing, and (c) to disclose the influence of BH on the RA PWV.Approach.The high-resolution remote breathing monitoring method Sorption-Enhanced Infrared Thermography (SEIRT) and the new technique aimed at measuring RA PWV described in this paper were used synchronously, and their measurement data were processed simultaneously.Main results. Spontaneous breathing leaves a synchronous 'trace' on the RA PWV. The close linear correlation of the respiration phase and the phase of concomitant RA PWV changes is statistically confirmed in five tested people (Pearson's r is of the order of 0.5-0.8, P < 0.05). The BH appreciably affects the RA PWV. A phenomenon showing that the RA PWV is not indifferent to hypoxia is observed for the first time.Significance.The proposed technique for RA PWV characterization has high prospects in biomedical diagnostics. The presented pilot study deserves attention in the context of the mutual interplay between respiratory and cardiovascular systems. It may also be useful in cases where peripheral pulse wave propagation helps assess respiratory function.

Left Internal Mammary Artery as an Endocrine Organ: Insights Into Graft Biology and Long-term Impact Following Coronary Artery Bypass Grafting

The left internal mammary artery (LIMA) is considered the criterion standard vessel for use in coronary artery bypass grafting. In recent decades, countless studies have documented its superiority over other arterial and venous coronary artery bypass grafting conduits, although the full mechanisms for this superiority remain unknown. A growing body of literature has unveiled the importance of extracellular vesicles known as exosomes in cardiovascular signaling and various pathologic states. In this review, we briefly compare the clinical longevity of the LIMA relative to other conduits, explore the effects of varying grafting techniques on clinical and angiographic outcomes, and provide physiologic insights into graft function on a cellular and molecular level. Finally, we explore exosome signaling as it pertains to atherosclerosis in support of the LIMA as an "endocrine organ."

Utility of a smartphone application in assessing palmar circulation prior to radial artery harvesting for coronary artery bypass grafting: rationale and design of the randomised CAPITAL iRADIAL-CABG trial

INTRODUCTION

There is emerging evidence supporting the use of the radial artery (RA) as a preferred secondary conduit for coronary artery bypass grafting (CABG) as it is associated with higher rates of graft patency at 5 years when compared with saphenous vein grafts (SVG). The modified Allen's test (MAT) is traditionally regarded as the standard of care in the assessment of ulnar artery (UA) patency prior to RA harvesting. Unfortunately, due to high false-positive rates, a substantial number of pre-CABG patients are found to have an abnormal MAT despite normal UA patency, resulting in inappropriate exclusion from RA harvesting. The SVG is generally used in its place when this occurs, resulting in potentially lower rates of long-term graft patency.

METHODS AND ANALYSIS

The CAPITAL iRADIAL-CABG trial is currently enrolling participants 18 years of age or older undergoing CABG for whom the treating physician is considering the use of an RA conduit. Eligible patients will be randomised in a 1:1 fashion to MAT or smartphone-based photoplethysmography application assessment to assess collateral palmar circulation prior to RA harvesting. The primary outcome of the trial is the use of the RA as a conduit during CABG. The primary safety outcome is postoperative palmar ischaemia as determined by clinical assessment or requirement of vascular intervention. Secondary outcomes include vascular complications, early graft failure, need for rescue percutaneous coronary intervention during the index hospitalisation and a composite cardiovascular outcome of myocardial infarction, stroke and cardiovascular death prior to discharge from hospital. A total of 236 participants are planned to be recruited.

ETHICS AND DISSEMINATION

The study was approved by the Ottawa Heart Science Network Research Ethics Board (approval number 20180865-01H). The study results will be disseminated via conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03810729.

Comparison of patency of single and sequential radial artery grafting in coronary artery bypass

OBJECTIVES

Sequential radial artery (RA) grafting has the potential to enhance arterial revascularization compared to single grafting. Sequential RA grafting was performed predominantly with a single side-to-side anastomosis. The study aimed to assess if sequential RA grafting improved long-term graft patency compared to single RA grafting. In addition, the anastomotic patencies of side-to-side and end-to-side anastomoses in sequential RA grafting were assessed.

METHODS

Two hundred nineteen patients underwent isolated coronary artery bypass grafting with skeletonized RA conduits between 2005 and 2016. Of these, 208 patients underwent radiological graft assessment; thus, 125 and 83 patients underwent single and sequential RA grafting, respectively. The graft and anastomotic patency rates were estimated using the Kaplan-Meier method.

RESULTS

The median follow-up period was 9.1 years, and the radiological assessment lasted 5.1 years. The overall RA graft patency rates at 1, 5 and 10 years were 99.4%, 92.7% and 88.1%, respectively. The RA graft patency rate for sequential grafting was similar to that for single grafting (88.7% vs 87.4% at 10 years; P = 0.88). In the stratified analysis of anastomotic patency, the patency rate of side-to-side anastomoses of sequential RA grafting was significantly better than that of end-to-side anastomoses (100% vs 88.7% at 10 years; P = 0.01).

CONCLUSIONS

The long-term RA graft patencies of sequential and single grafting were equally high. The anastomotic patency of side-to-side anastomoses of sequential RA grafting was remarkably high. Considering these findings, the RA can be effectively used for multiple arterial coronary revascularizations.

Translational model of vein graft failure following coronary artery bypass graft in atherosclerotic microswine

OBJECTIVE

Vein graft failure is a major complication following coronary artery bypass graft surgery. There is no translational model to understand the molecular mechanisms underlying vein-graft failure. We established a clinically relevant bypass graft model to investigate the underlying pathophysiological mechanisms of vein-graft failure and identify molecular targets for novel therapies.

METHODS

Six female Yucatan microswine fed with high cholesterol diet underwent off-pump bypass, using superficial epigastric vein graft, which was anastomosed to an internal mammary artery and distal left anterior descending artery. Vein-graft patency was examined 10-months after bypass surgery by echocardiography, coronary angiography, and optical coherence tomography followed by euthanasia. Coronary tissues were collected for histomorphometry studies.

RESULTS

Atherosclerotic microswine were highly susceptible to sudden ventricular fibrillation with any cardiac intervention. Two out of six animals died during surgery due to ventricular fibrillation. Selection of the anesthetics and titration of their doses with careful use of inotropic drugs were the key to successful swine cardiac anesthesia. The hypotensive effects of amiodarone and the incidence of arrhythmia were avoided by the administration of magnesium sulfate. The vein-graft control tissue displayed intact endothelium with well-organized medial layer. The grafted vessels revealed complete occlusion and were covered with fibrous tissues. Expression of CD31 in the graft was irregular as the layers were not clearly defined due to fibrosis.

CONCLUSION

This model represents the clinical vein-graft failure and offers a novel platform to investigate the underlying molecular mechanisms of vein-graft disease and investigate novel therapeutic approaches to prevent its progression.

Prediction value of EuroSCORE II in total arterial revascularization and its usage in the evaluation of postoperative complications: Single-center experience

BACKGROUND

Total arterial revascularization is the most durable and technically the most demanding type of coronary artery bypass grafting procedure. It has proven long-term supremacy in comparison to conventional coronary artery bypass grafting. In our study, we investigated the reliability of EuroSCORE II as a predictor of intrahospital death. We showed its impact on adverse perioperative events.

METHODS

In this nonrandomized prospective study, we analyzed 116 consecutive patients who underwent the total arterial revascularization procedure at our Institute from January 2011 until the present. For myocardial revascularization, the most suitable combinations with left internal mammary artery, right internal mammary artery, and radial artery grafts were used. Main fact in this research was intrahospital mortality value in comparison with the value predicted.

RESULTS

There were 104 (89.7%) males and 12 (10.3%) females. Mean preoperative EuroSCORE II prediction value was 1.98% and postoperative we obtained 1.72%. Postoperative redo for bleeding was 6%. Positive correlation was proven between the EuoroSCORE II value and intensive care unit stay (0.452; p < 0.001). Among patients who received two internal mammary arteries, the highest EuroSCORE II was among those with presternal wound infection (p = 0.005). Patients with bilateral internal mammary arteries and diabetes showed that they have the highest values of EuroSCORE II and, at the same time, that they are extremely prone to wound problems.

CONCLUSIONS

We achieved a lower intrahospital mortality level than it was predicted with preoperative EuroSCORE II value. This tool is a reliable method for preoperative death risk calculation in this group of patients.

Hybrid coronary revascularization versus total arterial revascularization for the treatment of left main coronary artery disease

BACKGROUND

Hybrid coronary revascularization (HCR) has a similar clinical outcome to coronary artery bypass grafting (CABG) in treating multivessel disease. However, the outcome of HCR in treating left main coronary artery (LM) disease is unclear. This study sought to compare the clinical outcome of HCR with total arterial revascularization (TAR) for treating LM disease.

METHODS

Patients who underwent treatment for LM disease in our center between January 2009 and December 2019 were selected. Of these, 33 patients underwent HCR, and 70 patients underwent TAR. The primary efficacy outcome of this study was mid-term major adverse cardiac and cerebrovascular events (MACCE). The primary safety outcome was perioperative MACCE.

RESULTS

The incidence of postoperative outcomes was comparable between the two groups after adjustment with inverse probability weighting (IPW) (P>0.05). The median follow-up time was 47 (interquartile range, 20 to 85) months. There was no significant difference in the incidence of all mid-term outcomes and the freedom of MACCE between the two groups after adjustment (P>0.05). The Cox proportional hazard model demonstrated that HCR was not a significant determinant for MACCE [hazard ratio (HR) =3.516, 95% confidence interval (CI): 0.835 to 14.813].

CONCLUSIONS

HCR may be safe and effective for the treatment of LM disease compared with TAR.

Coronary Artery Bypass: Review of Surgical Techniques and Impact on Long-Term Revascularization Outcomes

Coronary revascularization for multivessel disease remains a common and costly source of hospitalizations in the United States. Surgical techniques influence outcomes for coronary bypass and also affect the need for percutaneous coronary intervention in the future. As more radial access has been used for coronary angiography, consideration for use of the radial artery as a surgical conduit remains unclear. Saphenous vein grafts are commonly used for coronary bypass, however long-term patency remains suboptimal, and is also associated with a higher risk of adverse events with percutaneous coronary intervention. Thus, understanding the interplay between coronary bypass techniques and percutaneous coronary intervention has become increasingly important.

Long-term Outcomes Associated With Total Arterial Revascularization vs Non-Total Arterial Revascularization

Importance

The optimal conduits for coronary artery bypass grafting (CABG) remain controversial in multivessel coronary artery disease.

Objective

To compare the long-term clinical outcomes of total arterial revascularization (TAR) vs non-TAR (CABG with at least 1 arterial and 1 saphenous vein graft) in a multicenter population-based study.

Design, Setting, and Participants

This multicenter population-based cohort study using propensity score matching took place from October 2008 to March 2017 in Ontario, Canada, with a mean and maximum follow-up of 4.6 and 9.0 years, respectively. Individuals with primary isolated CABG were identified, with at least 1 arterial graft. Exclusion criteria were individuals from out of province and younger than 18 years. Patients undergoing a cardiac reoperation or those in cardiogenic shock were also excluded because these conditions would potentially bias the surgeon toward not performing TAR. Analysis began April 2019.

Exposures

Total arterial revascularization.

Main Outcomes and Measures

Primary outcome was time to first event of a composite of death, myocardial infarction, stroke, or repeated revascularization (major adverse cardiac and cerebrovascular events). Secondary outcomes included the individual components of the primary outcome.

Results

Of 49 404 individuals with primary isolated CABG, 2433 (4.9%) received TAR, with the total number of bypasses being 2, 3, and 4 or more vessels in 1521 (62.5%), 865 (35.6%), and 47 individuals (1.9%), respectively. The mean (SD) age was 61.2 (10.4) years and 1983 (81.5%) were men. After propensity score matching, 2132 patient pairs were formed, with equal total number of bypasses (mean [SD], 2.4 [0.5]) but with more arterial grafts in the TAR group (mean [SD], 2.4 [0.5] vs 1.2 [0.4]; P < .01). In-hospital death (15 [0.7%] vs 21 [1.0%]; P = .32) did not differ between TAR vs non-TAR groups after propensity score matching. Throughout 8 years, TAR was associated with improved freedom from major adverse cardiac and cerebrovascular events (hazard ratio, 0.78; 95% CI, 0.68-0.89), death (hazard ratio, 0.80; 95% CI, 0.66-0.97), and myocardial infarction (hazard ratio, 0.69; 95% CI, 0.51-0.92). There was no difference in stroke and repeated revascularization.

Conclusions and Relevance

Total arterial revascularization was associated with improved long-term freedom from major adverse cardiac and cerebrovascular events, death, and myocardial infarction and may be the procedure of choice for patients with reasonable life expectancy requiring CABG.

Assessment of the conventional radial artery with optical coherent tomography after the snuffbox approach

BACKGROUND

This study aimed to evaluate acute injuries of the radial artery (RA) using optical coherence tomography (OCT) in patients who underwent coronary intervention via the snuffbox approach.

METHODS

Forty-six patients, who underwent coronary intervention and assessment of the conventional RA using OCT via the snuffbox approach, were enrolled from two university hospitals between August 2018 and August 2019.

RESULTS

The mean age of the patients was 65.1 years. In this study population, 6-French (Fr) sheaths were used. The mean diameter of the conventional RA was 2.89 ± 0.33 mm, and the mean lumen area of the conventional RA was 6.68 ± 1.56 mm2. Acute injuries of the conventional RA, after the snuffbox approach, were observed in 5 (10.9%) patients. Intimal tear was observed in the RA in 1 (2.2%) case. Intraluminal thrombi, without vessel injuries, were detected in the RA in 4 (8.7%) cases. However, medial dissection was not observed in the OCT analysis.

CONCLUSIONS

This retrospective OCT-based study showed that the diameter of the conventional RA was 2.89 mm and acute vessel injury of the conventional RA was rare in patients who underwent coronary intervention via the snuffbox approach.

The no-touch saphenous vein is an excellent alternative conduit to the radial artery 8 years after coronary artery bypass grafting: A randomized trial

BACKGROUND

In 2004, a prospective randomized trial demonstrated that after 3 years, saphenous veins (SVs) harvested with a no touch (NT) technique had a greater patency than radial grafts for coronary bypass surgery. Here we report the 8-year follow-up data of this trial.

METHODS

The trial included 108 patients undergoing coronary artery bypass grafting (CABG). Each patient was assigned to receive 1 NT SV and 1 radial artery (RA) graft to either the left or right coronary territory to complement the left internal thoracic artery (LITA). Sequential grafting was common, so overall graft patency as well as the patency of each anastomosis were assessed.

RESULTS

Angiography was performed in 84 patients (78%) at mean of 97 months postoperatively. Graft patency were high and similar for both NT and RA: 86% for NT versus 79% for RA (P = .22). The patency of coronary anastomoses was significantly higher with the NT SV grafts (91% vs 81%; P = .046). The NT grafts also had excellent patency in coronary arteries with <90% stenosis (93% patency) and in coronary arteries of small diameter (87% patency) or with mild calcification (88% patency). Patency for the LITA was 92%.

CONCLUSIONS

NT SV grafts have excellent patency similar to that of RA grafts after 8 years. In addition, NT SV grafts can be used in situations that are not ideal for RA grafts.

21-Year Survival of Left Internal Mammary Artery-Radial Artery-Y Graft

BACKGROUND

In 1999, Royse et al. reported on the left internal mammary artery, radial artery, Y-graft technique (LIMA-RA-Y), which achieves total arterial revascularization (TAR). However, the most common coronary reconstruction remains LIMA and supplementary saphenous vein grafts (LIMA + SVG).

OBJECTIVES

The goal of this study was to conduct a survival comparison of LIMA-RA-Y versus the conventional LIMA + SVG.

METHODS

Of the original 464 LIMA-RA-Y patients reported (1996 to 1998), 346 were from the Royal Melbourne Hospital. Survival at June 2017 was compared with a group of 534 patients from 1996 to 2003 from the same institution who received LIMA + SVG, or 5,800 patients who received TAR with different grafting configurations. Propensity score matching (PSM) was performed with 1:1 matching using 26 variables. Comparisons used Kaplan-Meier (KM) and Cox proportional hazards methods. LIMA-RA-Y was compared with LIMA + SVG in which all non-left anterior descending artery grafts were performed with either composite RA or aorta-coronary SVG with no use of right internal mammary artery. We also conducted a comparison of LIMA-RA-Y versus TAR.

RESULTS

Baseline characteristics of the LIMA-RA-Y group (n = 346) compared with LIMA + SVG (n = 534) after PSM (n = 232 pairs) did not differ (3.3 ± 0.8 grafts per patient). Survival was worse for LIMA + SVG in the unmatched groups (KM, p < 0.001) and for PSM groups (KM, p = 0.043; Cox proportional hazards ratio: 1.3; 95% confidence interval: 1.0 to 1.6; p = 0.038). Survival did not differ between LIMA-RA-Y and other TAR (n = 5,800) patients before, or after, PSM (n = 332 pairs).

CONCLUSIONS

Use of LIMA + SVG has worse survival than LIMA-RA-Y in achieving total arterial revascularization.

The effect on survival from the use of a saphenous vein graft during coronary bypass surgery: a large cohort study

OBJECTIVES

Saphenous vein graft (SVG) remains the predominant conduit used in coronary surgery. The internal mammary artery has higher later term patency and confers superior survival. Current debate focuses on the increased use of arterial conduits rather than eradication of venous conduits.

METHODS

Patient data extracted from the Australian and New Zealand Society of Cardiothoracic Surgeons database from 2001-2013 were linked to the national death registry held by the Australian Institute of Health and Welfare for all-cause mortality with censor date 7 October 2014. The dataset was divided according to use of SVG rather than the arterial conduit. Analyses of SVG ≥ 1 or SVG = 1 were compared to SVG = 0. Additionally, groups of 3, 4 or 5 grafts were subjected to multiple analyses testing the mortality hazard with increasing use of SVG. Propensity score matched analyses were conducted using 24 variables.

RESULTS

Of 51 113 primary coronary surgery patients, unmatched survival at up to 12.5 years was significantly lower for SVG ≥ 1, n = 33 359, mortality hazard ratio (HR) 1.24 [95% confidence interval (CI) 1.18-1.30], P < 0.001; and for SVG = 1, mortality HR 1.19 (95% CI 1.12-1.26), P < 0.001. Similar results were present for the propensity score matched groups; SVG ≥ 1, n = 14 355 pairs, HR 1.22 (95% CI 1.15-1.30), P < 0.001; and for SVG = 1, n = 12 316 pairs, HR 1.22 (95% CI 1.14-1.30), P < 0.001. All matched analyses within restricted graft groups had increasing HR with increased number of SVG used.

CONCLUSIONS

Any use of SVGs is independently associated with reduced survival after coronary artery bypass surgery.

Autologous endothelialized vein allografts in coronary artery bypass surgery - Long term results

BACKGROUND

Lack of autologous graft material restricts the ability to treat patients requiring coronary artery bypass surgery (CABG). An off the shelf tissue engineered small diameter vascular graft is the holy grail of cardiovascular surgery.

METHODS

Allograft saphenous veins were harvested from organ donors, cryopreserved, deendothelialized and then seeded with autologous endothelial cells prior to implantation during coronary artery bypass surgery. All patients treated were followed-up until death and angiographic results were collected. Grafts were explanted during autopsy and immunohistochemistry was performed.

RESULTS

Twelve patients received 15 engineered grafts. Mean patient survival was 9.1 ± 1.8 years. Six month graft patency was 80 (95% CI: 59-100) and 9 month graft patency was 50 (95% CI: 27-93) - graft patency detected up to 32 months after surgery. Immunohistochemistry in grafts explanted showed a presence of CD31 and CD68 positive cells in the luminal region of the vessel walls and layers of Collagen Type I in the abluminal vessel walls.

CONCLUSIONS

Our small diameter tissue engineered vascular graft shows openness up to 32 months after implantation. Immunohistochemistry suggests that monocyte activation may lead to vessel remodeling with thickening of the vessel wall. Research should concentrate on a manipulation of remodeling processes.

Radial Artery Versus Saphenous Vein Grafts in Coronary Artery Bypass Surgery: a Literature Review

PURPOSE OF REVIEW

Coronary artery bypass grafting is a preferred strategy for complete coronary revascularization in patients who have multi-vessel coronary artery disease, left ventricular dysfunction, and/or diabetes. Both arterial (internal thoracic artery/radial artery) and venous grafts are utilized to bypass the obstruction in native vessels. Despite having radial arterial grafts as a preferred second conduit for bypass, venous grafts are more commonly used.

RECENT FINDINGS

We review the existing literature and report the preferred conduit based on a recently published meta-analysis of 6 randomized controlled trials. The analysis concluded that radial artery grafts are associated with fewer adverse cardiac events and better graft patency at 5 years of follow-up. Although saphenous vein grafting is the most commonly used conduit in addition to ITA, current data suggests that total arterial bypass (using RA conduit in addition to ITA) may be the better strategy. Both the US and European consensus guidelines advocate for the use of arterial over SV grafting for most patients.

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.

Fate of Grafts Bypassing Nonischemic Versus Ischemic Inducing Coronary Stenosis

There is a lack of evidence regarding the efficacy of ischemia-guided coronary artery bypass grafting. We compared the incidence of graft failure between grafts bypassing ischemia-inducing and nonischemia-inducing stenoses. Between 1997 and 2011, 2,304 patients for whom baseline coronary angiography and myocardial perfusion imaging were available were identified from a single-center coronary artery bypass grafting registry. According to baseline myocardial perfusion imaging, each graft was assigned to either graft bypassing ischemia-inducing or nonischemia-inducing stenoses (ischemia-related grafts, n = 4,904; ischemia-unrelated grafts, n = 2,709). Graft failure was defined as total occlusion on coronary computed tomography angiography, performed at the discretion of the treating physician. The incidence of graft failure was compared on a per-graft basis. At 5 years, the incidence of graft failure was significantly higher in the ischemia-unrelated grafts (4.2% vs 2.9% in ischemia-related grafts; p = 0.003). Ischemia-related graft was an independent determinant of graft patency (adjusted hazard ratio 0.61; 95% confidence interval 0.44 to 0.84; p = 0.002). Increased risk of graft failure associated with ischemia-unrelated graft was observed only in the internal thoracic artery (3.3% vs 2.0%, p = 0.021) and arterial grafts (6.5% vs 4.3%, p = 0.020), but not in the venous grafts (2.7% vs 2.7%; p = 0.99). In terms of major adverse cardiac and cerebrovascular events, 5-year incidences were comparable between the patients with and without ischemia-unrelated grafts (219, 19.3% vs 160, 18.0%; p = 0.61). In conclusion, ischemia-unrelated grafts became dysfunctional more frequently than ischemia-related grafts, and were not preventive of adverse events.

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.

A Prospective Randomized Study of Endoscopic Versus Conventional Harvesting of the Radial Artery

OBJECTIVE

The aims of the study were to determine whether endoscopic harvesting of the radial artery (RA) reduces morbidity due to pain, infection, and disability with improvement in satisfaction and cosmesis compared to the conventional technique and (2) to compare the 6-month angiographic patency of the RA harvested conventionally and endoscopically.

METHODS

In a prospective randomized study, 119 patients undergoing coronary artery bypass grafting using the RA were randomized to have RA harvested either conventionally (n = 59) or endoscopically (n = 60).

RESULTS

Radial artery harvest time (open wound time) was significantly reduced in the endoscopic group (36.5 ± 9.4 vs 57.7 ± 9.4 minutes, P < 0.001). Only one patient developed wound infection (1.6%) in the endoscopic group compared with six patients (10.2%), P = 0.061, in the conventional group. Although this was not statistically significant, clinically this was relevant in terms of reduction in postoperative morbidity. Postoperative pain in the arm incision was significantly lower in the endoscopic group at postoperative day 2 (P < 0.001) and at discharge (P < 0.001) and similar to the conventional open group at 6 weeks' follow-up (P = 0.103). Overall patient satisfaction and cosmesis were significantly better in the endoscopic group at postoperative day 2 (P < 0.001), at discharge (P < 0.001), and at 6 weeks' follow-up (P < 0.001). There was no difference in the arm disability postoperatively (P = 0.505) between the two groups. Six-month angiographic assessment of 23 patients (12 endoscopic and 11 open) revealed no difference in the patency rate (10/12 in endoscopic and 9/11 in open group).

CONCLUSIONS

Endoscopic RA harvesting reduced the incidence of postoperative wound infection and wound pain and improved patient satisfaction and cosmesis compared with conventional harvesting technique. There was no difference in the 6-month angiographic patency of the RA harvested conventionally and endoscopically.

Taurine relaxes human radial artery through potassium channel opening action

The vascular actions and mechanisms of taurine were investigated in the isolated human radial artery (RA). RA rings were suspended in isolated organ baths and tension was recorded isometrically. First, a precontraction was achieved by adding potassium chloride (KCl, 45 mM) or serotonin (5-hydroxytryptamine, 5-HT, 30 µM) to organ baths. When the precontractions were stable, taurine (20, 40, 80 mM) was added cumulatively. Antagonistic effect of taurine on calcium chloride (10 µM to 10 mM)-induced contractions was investigated. Taurine-induced relaxations were also tested in the presence of the K⁺ channel inhibitors tetraethylammonium (1 mM), glibenclamide (10 µM) and 4-aminopyridine (1 mM). Taurine did not affect the basal tone but inhibited the contraction induced by 5-HT and KCl. Calcium chloride-induced contractions were significantly inhibited in the presence of taurine (20, 40, 80 mM) (p<0.05). The relaxation to taurine was inhibited by tetraethylammonium (p<0.05). However, glibenclamide and 4-aminopyridine did not affect taurine-induced relaxations. Present experiments show that taurine inhibits 5-HT and KCl-induced contractions in RA, and suggest that large conductance Ca²⁺-activated K⁺ channels may be involved in taurine-induced relaxation of RA.

Radial Artery as a Coronary Artery Bypass Conduit: 20-Year Results

BACKGROUND

There is a lack of evidence for the choice of the second conduit in coronary surgery. The radial artery (RA) is a possible option, but few data on very-long-term outcomes exist.

OBJECTIVES

This study describes 20-year results of RA grafts used for coronary artery bypass grafting and the effects of RA removal on forearm circulation.

METHODS

We report the results of the prospective 20-year follow-up of the first 100 consecutive patients who received the RA as a coronary bypass conduit at our institution.

RESULTS

Follow-up was 100% complete. There were 64 deaths, 23 (35.9%) from cardiovascular causes. Kaplan-Meier 20-year survival was 31%. Of the 36 survivors, 33 (91.6%) underwent RA graft control at a mean of 19.0 ± 2.5 years after surgery. The RA was found to be patent in 24 cases (84.8% patency). In the overall population, probability of graft failure at 20 years was 19.0 ± 0.2% for the left internal thoracic artery (ITA), 25.0 ± 0.2% for the RA, and 55.0 ± 0.2% for the saphenous vein (p = 0.002 for RA vs. saphenous vein, 0.11 for RA vs. ITA, and p < 0.001 for ITA vs. saphenous vein). Target vessel stenosis >90%, but not location of distal anastomosis, significantly influenced long-term RA graft patency. No patients reported hand or forearm symptoms. The ulnar artery diameter was increased in the operated arm (2.44 ± 0.43 mm vs. 2.01 ± 0.47 mm; p < 0.05) and correlated with the peak systolic velocity of the second palmar digital artery (Pearson coefficient: 0.621; p < 0.05).

CONCLUSIONS

The 20-year patency rate of RA grafts is good, and not inferior to the ITA, especially when the conduit is used to graft a vessel with >90% stenosis. RA harvesting does not lead to hand or forearm symptoms, even at a very-long-term follow-up.

Radial artery vs saphenous vein graft used as the second conduit for surgical myocardial revascularization: long-term clinical follow-up

Background

There is ongoing debate regarding the efficacy of the radial artery (RA) as an aortocoronary conduit, with few solid data regarding long-term clinical results. We sought to determine if the use of the RA as the second arterial conduit, beside left internal thoracic artery (LITA), would improve long-term clinical outcome after CABG as compared to saphenous vein graft (SVG).

Methods

Between March 2001 and November 2003, 200 patients underwent isolated CABG and were randomized in 1:1 fashion to receive either LITA and RA grafts or LITA and SVGs. The primary end point was composite of cardiovascular mortality, non-fatal myocardial infarction and need for repeat myocardial revascularization (either surgical or percutaneous).

Results

There was no significant difference in absolute survival, with 12 deaths in each group during the study period (log rank = 0.01, p = 0.979). There were 3 and 2 cardiac deaths in RA and SVG groups, respectively. There was no difference in long-term clinical outcome between the groups (log rank = 0.450, p = 0.509). Eleven patients in RA group had one or more non-fatal events; 7 patients suffered a myocardial infarction, 9 patients underwent percutaneous coronary angioplasty, and 1 patient required redo coronary surgery. Likewise, 13 patients in SVG group had non-fatal event; 7 patients had myocardial infarction, 13 patients had percutaneous coronary intervention and 3 patients required redo coronary surgery. Angiograms were performed in 23 patients in RA group (patency rate 92 %) and 24 in SVG group (patency rate 86 %) (p = 0.67).

Conclusion

In this small randomised study our data indicate that there is no difference in the 8 year clinical outcomes in relatively young patients between those having a RA or a saphenous vein graft used as a second conduit, beside LITA, for surgical myocardial revascularisation.

Mid-Term Patency in Radial Artery and Saphenous Vein After Coronary Artery Bypass Grafting in Asymptomatic Patients Using 128-Slice CT Coronary Angiography

Background:

Patency of the revascularization conduit is an essential predictor of long-standing survival after coronary artery bypass grafting.

Objectives:

We have conducted this study to compare the mid-term patency rates of radial artery (RA), left internal thoracic artery (LITA) and also saphenous vein (SV) grafts in asymptomatic patients following coronary artery bypass graft surgery (CABG) undergoing total IV anesthesia.

Patients and Methods:

In this study, 30 three-vessel disease patients with 104 RA, LITA, and SV grafts used concomitantly for primary isolated non-emergent CABG surgery were assessed. The primary end point was CT angiographic graft patency rate. After 53.5 (24-97) months’ follow-up, graft patency was assessed using 128-slice CT coronary angiography. Logistic regression analysis was used to detect the independent predictors of graft failure.

Results:

A total of 104 grafts, including 30 LITA, 44 SV, and 30 RA grafts, were studied. Cumulative graft patency rates were 93.3% in LITA, 83.3% in RA, and 70.5% in SV grafts. Statistically significant difference was found between the LITA and the SV graft patency rates (P = 0.019), whereas the difference between the RA conduit patency and the LITA or SV graft patency rates did not have any statistical significance (P = 0.424 and P = 0.273, respectively). Independent predictors of RA grafts occlusion were native coronary stenosis < 70% and female gender.

Conclusions:

In our patients, the RA grafts had an acceptable patency rate in 2 to 5 years’ follow-up. Although the SV grafts had a relatively higher patency rate than RA grafts in our asymptomatic patients, the patency rates in RA and SV grafts were close to each other. The RA graft function was poor in the patients with a higher number of risk factors and in the females.

Morphological and functional consequences of transradial coronary angiography on the radial artery: implications for its use as a bypass conduit

OBJECTIVES

To assess the degree of damage to the radial artery (RA) in coronary artery bypass grafting (CABG) patients who underwent preoperative transradial coronary angiography (RA-CA).

METHODS

From May 2012 to October 2013, 50 consecutive CABG patients who underwent RA-CA were prospectively enrolled in the study. All patients underwent echo-Doppler evaluation of the RA of the catheterized arm; the contralateral RA was used as control. The distal segment of the RA was submitted to immunohistochemical assessment of endothelial integrity. Patients were divided in three groups according to the time interval from angiography to evaluation: ≤24 h, >24 h to <7 days and ≥7 days.

RESULTS

Baseline RA median diameters were 0.25 ± 0.04 cm in the cannulated arm and 0.22 ± 0.04 cm in the non-cannulated arm (P = 0.01). The flow-mediated dilatation (FMD) in the RA in the catheterized arm and in the control arm were 11.6 ± 7.9 and 14.2 ± 8.9 (P = 0.01), respectively. A statistically significant correlation was found between FMD of the catheterized RA and the time from RA-CA (Pearson's r = 0.348). Linear regression analysis confirmed that the FMD of the catheterized RA was dependent on days elapsed from the procedure (P = 0.032; OR 1.11, CI 0.009-0.203). Immunohistochemical evaluation showed extensive endothelial lesion in all examined RAs, with a trend towards reduction of the damage with time. Endothelial function and integrity of the cannulated arm did not reach those of the control arm in any of the study patients.

CONCLUSIONS

RA-CA produces extensive damage to the RA. The lesions tend to heal with time but incomplete recovery of endothelial integrity and function is still present more than 30 days after the procedure. After RA-CA, the cannulated RA should not be used for CABG.

Coronary artery bypass graft: why is the saphenous vein prone to intimal hyperplasia?

Proliferation and migration of smooth muscle cells and the resultant intimal hyperplasia cause coronary artery bypass graft failure. Both internal mammary artery and saphenous vein are the most commonly used bypass conduits. Although an internal mammary artery graft is immune to restenosis, a saphenous vein graft is prone to develop restenosis. We found significantly higher activity of phosphatase and tensin homolog (PTEN) in the smooth muscle cells of the internal mammary artery than in the saphenous vein. In this article, we critically review the pathophysiology of vein-graft failure with detailed discussion of the involvement of various factors, including PTEN, matrix metalloproteinases, and tissue inhibitor of metalloproteinases, in uncontrolled proliferation and migration of smooth muscle cells towards the lumen, and invasion of the graft conduit. We identified potential target sites that could be useful in preventing and (or) reversing unwanted consequences following coronary artery bypass graft using saphenous vein.

Which is the best graft for the right coronary artery?

Bilateral internal mammary arteries directed to the left coronaries are gaining popularity; an increasing level of evidence nowadays supports this surgical strategy. On the other hand, composite right internal mammary artery, radial artery, and gastroepiploic artery targeting high-grade stenotic lesions in the right coronary artery system may confer improved mid- and long-term patency compared to long saphenous veins. This analysis looks into the evidence comparing data of the third best available conduit for grafting the right coronary artery, and by extrapolating this report, compares total arterial revascularization vs. conventional coronary artery bypass grafting.

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.

Radial artery for coronary artery bypass grafting: does proximal anastomosis to the aorta or left internal mammary artery achieve better patency?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'in coronary artery bypass grafting using radial artery grafts, does proximal anastomosis to the aorta or left internal mammary artery achieve better patency'. Altogether >183 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Radial artery grafts typically have a narrower lumen than vein grafts, and as such there is some concern that anastomosing them directly to the aorta during coronary artery bypass grafting (CABG) may impair graft patency. As such, some surgeons prefer to anastomose radial artery grafts to a second-order vessel such as the left internal mammary artery (LIMA). We sought to assess the evidence for this. A handful of papers directly addressing the issue of the effect of the site of proximal anastomosis on graft patency were found, with three showing no significant difference. One such study reported an insignificant difference in angiographic patency at 32 months postoperatively, with 94.1% of off-aorta grafts remaining patent vs 87.2% of off-LIMA grafts (p = 0.123). However, a large-scale well-designed study was able to demonstrate a statistically significant difference at five years postoperatively, with 74.3% of off-aorta grafts patent, compared with 65.2% of off-LIMA (p = 0.004). Nonetheless, a number of papers that report patency for either off-aorta or off-LIMA grafts give comparable figures for each technique. Additionally, different centres and investigators report very different patency results for grafts that have the same site of proximal anastomosis. One centre was able to achieve patency rates for off-LIMA grafts of 88% up to a mean of 7.7 years postoperatively while another centre reported a patency rate of only 78.6% at three years. Given this, and the plethora of other factors influencing graft patency, we conclude that the best evidence suggests that the site of proximal anastomosis has little or no effect on radial artery graft patency following CABG.

Coronary artery bypass graft surgery using the radial artery as a secondary conduit improves patient survival

BACKGROUND

The clinical benefits of the left internal thoracic artery-to-left anterior descending coronary artery graft are well established in coronary artery bypass graft surgery (CABG). However, limited data are available regarding the long-term outcome of the radial artery (RA) as a secondary conduit over the established standard of the saphenous venous graft.

METHODS AND RESULTS

We compared the 12-year survival outcome in a set of propensity-matched CABG patients who received either the RA or the saphenous vein as a secondary conduit. A multivariable logistic regression that included 18 baseline characteristics was used to define the propensity of receiving an RA graft. The propensity model resulted in 260 matched pairs who underwent first-time isolated CABG from 1996 to 2001 with similar preoperative characteristics (C statistic=0.86). The cumulative 12-year survival estimated by use of the Kaplan-Meier method was higher for the RA graft patients (hazard ratio 0.76; P=0.03). This survival advantage was especially significant in diabetics (P=0.005), in women (P=0.02), and in the elderly (P=0.04.) The protective effect appeared beginning at year 5 post surgical intervention.

CONCLUSION

The RA as a secondary conduit provided superior long-term survival after CABG, especially in diabetic patients, women, and the elderly. This effect was most pronounced >5 years after surgery.

A novel composite coronary bypass graft strategy: the saphenous vein bridge--a pilot study

OBJECTIVES

The aim of this pilot study was to describe and assess the safety of a novel composite graft technique for coronary artery bypass grafting (CABG) surgery. A saphenous vein is grafted to the left anterior descending artery (LAD) and other anterolateral coronary arteries, creating a saphenous vein bridge (SVB) and the left internal mammary artery (LIMA) is anastomosed to the SVB, distributing the blood flow distally (LIMA-SVB).

METHODS

All patients who underwent CABG with the LIMA-SVB between 2005 and 2008 at our centre were enrolled in this study. Perioperative data were retrospectively collected from hospital charts, and the clinical follow-up was completed by telephone interview. Graft patency was assessed by computed tomography angiography (CTA) in patients with the longest follow-up time (n = 20).

RESULTS

A total of 256 patients (mean age: 67 ± 12 years; 79% male) received 4.0 ± 1.0 grafts, including 2.2 ± 0.4 distal grafts provided by the LIMA-SVB. Nine (3.5%) deaths and 4 (1.6%) myocardial infarctions (MIs) were noted in the perioperative period. With a median follow-up time of 36 months [inter-quartile range 31-44], 1 (0.5%) MI and 2 (1.0%) strokes were reported. At 51 months post-surgery [47-53], CTA demonstrated a LIMA pedicle (n = 20) and SVB (n = 42) patency rate of 100 and 93%, respectively. Specifically, the LIMA-SVB patency rate was 100% to the LAD and 85% to diagonal arteries. Aortocoronary vein grafts (n = 38) patency rate in the same patients was 87%.

CONCLUSIONS

Revascularization of the anterolateral territory using the LIMA-SVB is a promising approach considering its clinical safety and favourable patency rate results. A prospective randomized clinical trial is underway to compare this technique to conventional CABG.

Comparative study on the histomorphology and molecular biology of radial artery conduits in patients with diabetes mellitus who underwent coronary bypass surgery

We studied the impact of diabetes mellitus (DM) on the radial artery (RA) in 30 patients with DM and 30 non-diabetic patients undergoing coronary artery bypass grafting with autologous RA. RAs were recorded as normal if there was no cellular or stromal tissue between the endothelium and the internal elastic lamina. The RA was normal in 26.7% of diabetic and 76.7% of non-diabetic patients (p = 0.000298). Intimal thickness index and intima:media ratio were higher in the former than in the latter (p < 0.05; p < 0.05), with no significant difference in luminal narrowing (p > 0.05). Electron microscopy scores were lower in the non-diabetic group (p < 0.001); endothelial nitric oxide synthase (eNOS) protein expression and optical density were higher (p < 0.001). Von Willebrand factor and endothelin-1 messenger RNA (mRNA) levels were higher in the DM patients (p < 0.001). The quality of the RA in patients with DM was thus inferior to that in non-diabetic patients. Care should be taken when selecting RA as a conduit in patients with DM.

Impact of Transradial Coronary Procedures on Radial Artery Function

We evaluated the impact of transradial coronary procedures on the vasodilatory function of the radial artery. A total of 65 patients who underwent transradial coronary procedures were enrolled. All patients were examined with B-mode high-resolution ultrasound. Radial artery baseline diameter and response to flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD) were measured in the right radial artery. The FMD of the right radial artery was 11.5%, 4.1%, and 0.7%, respectively, before the procedures, 1 day, and 3 months after the procedures ( P < .05 at 1 day, P < .01 at 3 months). The NMD of the right radial artery was 17.6%, 5.4%, and 6.3%, respectively, before the procedures, 1 day, and 3 months after the procedures ( P < .05 at 1 day, P < .05 at 3 months). Transradial coronary procedures decrease radial artery FMD and NMD resulting in immediate and persistent blunting of vasodilatory function.

Safety of the extended radial artery conduit in performing complete arterial revascularization

PURPOSE

We have developed a technique to elongate the radial artery (RA) with the distal segment of the left internal thoracic artery. This study investigated the safety and durability of this extended conduit compared with the composite Y-grafts.

METHODS

From January 1998 through December 2010, 750 patients underwent complete arterial revascularization with the use of the left internal thoracic artery (LITA) and RA. Out of these patients, 362 patients were operated on with the use of either RA-LITA extension conduit (n = 103), or a composite LITA-RA Y-graft (n = 259) and were included in this study. Cox regression analyses and Kaplan-Meyer survival curves were used to identify the predictive value of the RA-LITA extension technique on both survival and incidence of re-intervention.

RESULTS

Cox regression analysis showed that the use of RA-LITA extension conduit was not a significant predictor of re-intervention (p = 0.600) or total survival (p = 0.930).Kaplan-meier curves showed no significant difference between the two groups concerning total survival and re-intervention-free survival (p = 0.600).

CONCLUSIONS

Our alternative technique of extending the RA with the distal segment of the LITA is a safe alternative for patients undergoing total arterial revascularization. The long-term survival and incidence of re-intervention is comparable with the composite LITA-RA Y-grafts.