Radial artery versus saphenous vein as the second conduit for coronary artery bypass surgery: A meta-analysis

Quality improvement initiative to increase radial artery usage as a second arterial conduit in coronary artery bypass grafting

OBJECTIVES

Use of radial artery as a second arterial graft, compared to a saphenous vein, in coronary artery bypass grafting (CABG) can improve late outcomes. However, the radial artery remains underutilized. We initiated a quality improvement (QI) initiative to increase the usage of radial artery grafts.

METHODS

During our 4-month lead period, we disseminated evidence for radial artery graft usage to surgeons, developed a radial artery decision-making algorithm and adopted endoscopic harvesting. Our QI initiative was conducted over a 6-month period and included a postoperative survey of decision-making for graft selection and obstacles to radial artery usage.

RESULTS

Over the 6-month study period, 247 patients received isolated CABG which included 98 (40%) with radial arteries as a second arterial graft and 144 (58%) with greater saphenous veins. Radial artery usage increased with QI initiative implementation by 67% compared to 6 months prior to the study period (60 radial arteries/252 isolated CABG, 24%) (P = 0.006). The survey response rate was 93% (231/247). Barriers to radial artery graft usage were poor quality target vessel or stenosis <80% (24%), patient age >75 years (20%), ejection fraction ≤35% (8%) and renal insufficiency/dialysis (7%). No patients experienced significant complications from radial artery harvest.

CONCLUSIONS

Our institutional QI initiative was successful in (i) increasing the usage of radial artery as a second arterial graft and (ii) understanding barriers to radial artery graft usage. Implementation of a QI program can improve radial artery usage in CABG with low risk of patient morbidity from radial artery harvest.

Bilateral internal thoracic artery versus single internal thoracic artery plus radial artery: A double meta-analytic approach

OBJECTIVES

We explored the current evidence on the best second conduit in coronary surgery carrying out a double meta-analysis of propensity score matched or adjusted studies comparing bilateral internal thoracic artery (BITA) versus single internal thoracic artery plus radial artery.

METHODS

PubMed, Embase, and Google Scholar were searched for propensity score matched or adjusted studies comparing BITA versus single internal thoracic artery plus radial artery. The end point was long-term mortality. Two statistical approaches were used: the generic inverse variance method and the pooled meta-analysis of Kaplan-Meier-derived individual patient data.

RESULTS

Twelve matched populations comparing 6450 patients with BITA versus 9428 patients with single internal thoracic artery plus radial artery were included in our meta-analysis. The generic inverse variance method showed a statistically significant survival benefit of the BITA group (hazard ratio, 0.84; 95% CI, 0.74-0.95; P = .04). The Kaplan-Meier estimates of survival at 1, 5, 10, and 15 years of the BITA group were 97.0%, 91.3%, 80.0%, and 68.0%, respectively. The Kaplan-Meier estimates of survival at 1, 5, 10, and 15 years of the single internal thoracic artery plus radial artery group were 97.3%, 91.5%, 79.9%, and 63.9%, respectively. The Kaplan-Meier-derived individual patient data meta-analysis applied to very long follow-up time data, showed that BITA provided a survival benefit after 10 years from surgery (hazard ratio, 0.77; 95% CI, 0.63-0.94; P = .01). No differences in terms of survival between the 2 groups were detected when the analysis was focused on the first 10 years of follow-up (hazard ratio, 0.99; 95% CI, 0.91-1.09; P = .93).

CONCLUSIONS

The present meta-analysis suggests that double internal thoracic artery may provide, compared with single internal thoracic artery plus radial artery, a statistically significant survival advantage after 10 years of follow-up, but not before. VIDEO ABSTRACT.

The VEST External Support for Saphenous Vein Grafts in Coronary Surgery: A Review of Randomized Clinical Trials

Saphenous vein grafts (SVGs) are the most frequently used conduits in coronary artery bypass grafting (CABG), but their higher rate of occlusion compared to arterial conduits remains a concern. Previous studies have shown that SVG failure is mainly driven by intimal hyperplasia, an adaptative response to higher pressures of the arterial circulation. The VESTTM device (Vascular Graft Solutions, Tel Aviv, Israel), an external support designed to mitigate intimal hyperplasia in SVGs, has been tested in few clinical trials (RCTs). Herein, we descriptively evaluated the randomized evidence on the VEST device.

Subclinical Leaflet Thrombosis Following Surgical and Transcatheter Aortic Valve Replacement: A Meta-Analysis

Subclinical leaflets valve thrombosis (SLT) is a recently identified phenomenon with multidetector computer tomography after tissue aortic valve replacement. Whether SLT is more frequent after transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) is currently not known. Thus, the aim of this pairwise meta-analysis was to investigate the incidence of SLT after both TAVR and SAVR, the association with anticoagulation therapy, and the risk for neurological events. We searched PubMed, Google Scholar, and Ovid MEDLINE/Embase (January 02, 2023, last update) (PROSPERO registration: CRD42022383295). Statistical analysis was performed according to a prespecified statistical analysis plan. Time-to-event outcomes were summarized as incidence rate ratios (IRR). Pooled estimates were calculated using inverse variance method and random effect model. Overall, 2 registries, 2 randomized trials, and 1 observational study (1,593 patients) were included in this meta-analysis. There was a statistically significant difference in the incidence rate at follow-up of SLT between patients who underwent TAVR and SAVR (IRR 2.07, 95% confidence interval [CI]: [1.06; 4.03], I2 79%, 95% CI: [44; 92], p = 0.03). Oral anticoagulation therapy was associated with a reduced incidence of SLT (IRR 7.51, 95% CI: [3.24; 17.37], I2 62%, 95% CI: [0; 87], p <0.001). However, the incidence of later neurological events did not differ between patients with or without SLT (IRR 1.05, 95% CI: [0.32; 3.47], p = 0.93). In conclusion, SLT was more frequently detected after TAVR than SAVR. However, it was not associated with an increased risk for neurological events. Oral anticoagulation therapy seemed to reduce the incidence of SLT.

Risk factors for major adverse cardiovascular events after coronary artery bypass grafting using radial artery grafts

Background

Coronary artery bypass grafting using radial artery grafts (RA-CABG) has improved long-term outcomes. However, major adverse cardiovascular events (MACE-4, including all-cause death, myocardial infarction, stroke, and repeat revascularization) after RA-CABG still occur and the predictors remain uncertain. This study aimed to detect independent risk factors of MACE-4 after RA-CABG.

Methods

This is a retrospective case-control study (NCT04935086) conducted among patients who underwent primary isolated RA-CABG between 2009 and 2019 in our center. Baseline characteristics, procedure characteristics, and medication use were compared to identify the independent predictors of MACE-4, all-cause death, and myocardial infarction (MI) with univariate and then multivariate logistic regression.

Results

A total of 370 patients were analyzed using a mean follow-up duration of 48.8 ± 41.0 months. MACE-4, all-cause death, and MI occurred in 102 (27.6%), 27 (7.3%), and 66 patients (17.8%), respectively. Multivariate analysis revealed prior MI (OR = 2.12, 95%CI 1.05-4.25, P = 0.04) and RA to the left anterior descending artery (LAD) (non-left internal mammary artery to LAD) (OR = 4.87, 95%CI 1.41-16.82, P = 0.01) as independent predictors of MACE-4 after surgery. Female (OR = 4.53, 95%CI 1.06-19.41, P = 0.04), left ventricular ejection fraction (LVEF) <40% (OR = 21.00, 95%CI 1.20-368.35, P = 0.04), and RA to LAD (OR = 8.55, 95%CI 1.35-54.10, P = 0.02) were independent predictors of all-cause death. Prior MI (OR = 3.11, 95%CI 1.40-6.94, P = 0.006) emerged as an independent predictor of MI.

Conclusion

Our data suggested that prior MI and RA to LAD were independent predictors of MACE-4 after RA-CABG. Being female, having an LVEF < 40% and RA to LAD indicated death. Prior MI indicated new MI.

Expert systematic review on the choice of conduits for coronary artery bypass grafting: endorsed by the European Association for Cardio-Thoracic Surgery (EACTS) and The Society of Thoracic Surgeons (STS)

PREAMBLE

The finalized document was endorsed by the EACTS Council and STS Executive Committee before being simultaneously published in the European Journal of Cardio-thoracic Surgery (EJCTS) and The Annals of Thoracic Surgery (The Annals) and the Journal of Thoracic and Cardiovascular Surgery (JTCVS).

Survival and Independent Predictors of Mortality Following Coronary Artery Bypass Graft Surgery in a Single-Unit Practice in the United Kingdom Over 20 Years

BACKGROUND

 The types of graft conduits and surgical techniques may impact the long-term outcomes of patients after coronary artery bypass graft (CABG) revascularization. This study observed a long-term survival rate following CABG surgery over 20 years in the United Kingdom.

METHODS

 A total of 2979 isolated CABG patients were studied from 1999 to 2020, and postoperative data were obtained from the hospital-recorded mortality by the data quality team of the information department. Postdischarge survival was estimated using the Kaplan-Meier method, and statistical significance was obtained with log-rank tests and the Gehan-Breslow test, and the Holm-Sidak method was used for multiple pairwise comparisons.

RESULTS

 The study observed male predominance (80%), and the median age was statistically significant (P <0.001) among the groups, 66 years (interquartile range 58-73) and 72 years (interquartile range 66-78) in survivor and non-survivor groups, respectively. In the Holm-Sidak method analysis, the best survival rate (mean 18.7 years) was observed in the total arterial group with significantly decreased survival for the mixed arterial and venous group (mean 16.12 years) and only the vein group (10.44 years). The Cox regression model observed that the New York Heart Association (NYHA) class III-IV (HR 1.57), chest re-exploration (HR 2.14), preoperative dialysis (HR 3.13), and redo surgery (HR 3.04) were potential predictors of the postoperative mortality (P ≤0.05).

CONCLUSION

 In our series over 20 years, albeit off-pump and on-pump CABG observed similar survival rates, the total arterial myocardial revascularization population has significantly better long-term survival benefits.

[Analysis of cardiac surgeries and operative mortality at the National Cardiovascular Institute during 2022]

Objective

To describe cardiac surgeries, their approaches, and determine operative mortality according to the type of surgery and the main complications recorded within 30 days postoperatively, performed at the National Cardiovascular Institute of Peru.

Materials and methods

A descriptive study was conducted on all patients over 18 years of age who underwent cardiovascular surgery at the National Cardiovascular Institute "Carlos Alberto Peschiera Carrillo".

Results

During the year 2022, a total of 503 cardiac surgeries were performed. Of the patients undergoing surgery, 63.6% (320) were males. Isolated valvular surgery, primarily aortic or mitral valve replacement, was the most frequent surgical procedure, with 136 surgeries (27.0%). This was followed by myocardial revascularization surgery with 110 procedures (21.9%). Throughout the year, there were 23 deaths, resulting in an overall mortality rate of 4.5%. The mortality rate for elective surgeries was 2.8%, while for emergency surgeries, it was 14.3%. The most common complication was paroxysmal atrial fibrillation (14.0%), followed by surgical site infection with 52 cases (10.3%).

Conclusions

Valvular surgery, whether isolated or combined with other procedures, was the most frequently performed. The obtained mortality rate is considered acceptable for a reference center.

Coronary artery bypass with single versus multiple arterial grafts in women: A meta-analysis

OBJECTIVE

The study objective was to investigate the impact of multiple arterial grafting on long-term all-cause mortality in women undergoing isolated coronary artery bypass grafting.

METHODS

A comprehensive search was performed to identify observational studies reporting outcomes after coronary artery bypass grafting reported by sex and stratified into multiple arterial grafting versus single arterial grafting strategies. Articles were considered for inclusion if they were written in English and were propensity-matched observational studies. Included studies were then pooled in a meta-analysis performed using the generic inverse variance method. The primary outcome was long-term all-cause mortality. Secondary outcomes were operative mortality and spontaneous myocardial infarction. Meta-regression was used to explore the effects of preoperative and intraoperative variables on the primary outcome.

RESULTS

A total of 6 studies with 32,793 women (25,714 single arterial grafting and 7079 multiple arterial grafting) were included. Women who received multiple arterial grafting had lower long-term mortality (incidence rate ratio, 0.86; 95% confidence interval, 0.76-0.96; P = .007) and spontaneous myocardial infarction (incidence rate ratio, 0.80; 95% confidence interval, 0.68-0.93; P = .003) compared with women who received single arterial grafting, but the difference in mortality disappeared when including only the 3 largest studies. There was no difference between groups in operative mortality (odds ratio, 0.99; 95% confidence interval, 0.84-1.17; P = .91). Meta-regression did not identify any associations with the incidence rate ratio for long-term mortality.

CONCLUSIONS

The use of multiple arterial grafting in women undergoing coronary artery bypass grafting is associated with lower long-term mortality, although the difference is mostly driven by small series. Further studies, including randomized trials, are needed to evaluate the efficacy of multiple arterial grafting in women undergoing coronary artery bypass grafting.

Acute Coronary Syndromes Among Patients with Prior Coronary Artery Bypass Surgery

PURPOSE OF REVIEW

Acute coronary syndromes (ACS) often occur in individuals with prior coronary artery bypass graft surgery (CABG). Our goal was to describe the prevalence, clinical characteristics, prognosis, and treatment strategies in this group of patients.

RECENT FINDINGS

Studies demonstrate that both acute and long-term major adverse cardiovascular outcomes are increased in patients with ACS and prior CABG compared to those without CABG. Much of this risk is attributed to the greater comorbid conditions present in patients with prior CABG. Data regarding optimal management of ACS in patients with prior CABG are limited, but most observational studies favor an early invasive approach for treatment. Native vessel percutaneous coronary intervention (PCI), if feasible, is generally preferred to bypass graft PCI. Patients with ACS and prior CABG represent a high-risk group of individuals, and implementing optimal preventive and treatment strategies are critically important to reduce the risk.

Percutaneous coronary intervention versus repeat surgical revascularization in patients with prior coronary artery bypass grafting: A systematic review and meta-analysis

Objectives

Repeat coronary artery bypass grafting (RCABG) and percutaneous coronary intervention (PCI) are both used for the treatment of symptomatic patients with coronary artery disease and prior CABG, but the optimal treatment strategy remains unknown. We sought to perform a systematic review and meta-analysis to compare operative and follow-up outcomes following RCABG versus PCI in patients with prior CABG.

Methods

Medline and Embase were searched for studies comparing RCABG versus PCI. The primary outcome was follow-up mortality, and secondary outcomes were follow-up repeat revascularization, operative mortality, periprocedural stroke, and myocardial infarction. Time-to-event outcomes were summarized as incidence rate ratios, whereas operative outcomes were summarized as odds ratios. A random effect meta-analysis was performed. Individual patient survival data was extracted from available survival curves and reconstructed using restricted mean survival time.

Results

Among 2982 articles, 7 studies (9945 patients) were included. In the aggregated data meta-analysis, there was no difference in follow-up survival between RCABG and PCI (incidence rate ratio, 1.02; 95% CI, 0.83-1.25); however, restricted mean survival time analysis of individual data showed a survival benefit for RCABG over PCI (0.7 years; 95% CI, 0.23-1.19 years; P = .004). PCI was found to have a higher incidence rate of follow-up need for repeat revascularization (incidence rate ratio, 1.61; 95% CI, 1.16-2.23), but lower odds for operative mortality and stroke. No difference in the odds for myocardial infarction was found.

Conclusions

In patients with prior CABG, PCI is associated with better operative outcomes, but RCABG is associated with better survival and freedom from repeat revascularization at follow-up.

Radial artery versus saphenous vein versus right internal thoracic artery for coronary artery bypass grafting

OBJECTIVES

We used individual patient data from 4 of the largest contemporary coronary bypass surgery trials to evaluate differences in long-term outcomes when radial artery (RA), right internal thoracic artery (RITA) or saphenous vein graft (SVG) are used to complement the left internal thoracic artery-to-left anterior descending graft.

METHODS

Primary outcome was all-cause mortality. Secondary outcome was a composite of major adverse cardiac and cerebrovascular events (all-cause mortality, myocardial infarction and stroke). Propensity score matching and Cox regression were used to reduce the effect of treatment selection bias and confounders.

RESULTS

A total of 10 256 patients (1510 RITA; 1385 RA; 7361 SVG) were included. The matched population consisted of 1776 propensity score-matched triplets. The mean follow-up was 7.9 ± 0.1, 7.8 ± 0.1 and 7.8 ± 0.1 years in the RITA, RA and SVG cohorts respectively. All-cause mortality was significantly lower in the RA versus the SVG [hazard ratio (HR) 0.62, 95% confidence interval (CI): 0.51-0.76, P = 0.003] and the RITA group (HR 0.59, 95% CI 0.48-0.71, P = 0.001). Major adverse cardiac and cerebrovascular event rate was also lower in the RA group versus the SVG (HR 0.78, 95% CI 0.67-0.90, P = 0.04) and the RITA group (HR 0.75, 95% CI 0.65-0.86, P = 0.02). Results were consistent in the Cox-adjusted analysis and solid to hidden confounders.

CONCLUSIONS

In this pooled analysis of 4 large coronary bypass surgery trials, the use of the RA was associated with better clinical outcomes when compared to SVG and RITA.

Coronary Artery Bypass Surgery After Transradial Catheterization

The 2021 ACC/AHA/SCAI coronary artery disease revascularization guideline recommends radial artery (RA) access for coronary angiography and RA grafting over saphenous vein grafting in patients referred for coronary artery bypass grafting. We present a case of a patient who underwent coronary angiography via both RAs and therefore could not receive RA bypass grafts. (Level of Difficulty: Advanced.)

Never again. Once used for cardiac catherization the radial artery cannot be used for CABG

The use of the radial artery (RA) as a conduit in coronary artery bypass grafting (CABG) has been steadily increasing since the early 1990s and based on the most recent data may well become the standard of care for patients with multivessel coronary artery disease requiring multiple arterial grafts. The transradial access (TRA) approach for cardiac catherization has also increased steadily in use by interventional cardiologists owing to its reduction in bleeding and vascular complications when compared with the femoral approach and is now considered the preferred arterial access. However, prior use of TRA for cardiac catherization is a contraindication for the use of the RA for CABG because of high rates of structural damage to the vascular wall and potential for graft failure. In this issue of the Journal of Cardiac Surgery Clarke et al. examine the RA of two patients who had TRA for coronary angiography 8 and 12 years prior and note that both patients had chronic injury with dissection and obstruction of the lumen secondary to fibrosis suggesting that TRA causes long-term and irreversible damage rendering them unsuitable as conduits for CABG.

Radial artery or saphenous vein for Coronary artery bypass grafitng

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

Cardiac Surgery 2020 Reviewed

In 2020, nearly 30,000 published references appeared in the PubMed for the search term "cardiac surgery." While SARS-CoV-2 affected the number of surgical procedures, it did not affect outcomes reporting. Using the PRISMA approach, we selected relevant publications and prepared a results-oriented summary. We reviewed primarily the fields of coronary and conventional valve surgery and their overlap with interventional alternatives. The coronary field started with a discussion on trial data value and their interpretation. Registry comparisons of coronary artery bypass surgery (CABG) and percutaneous coronary intervention confirmed outcomes for severe coronary artery disease and advanced comorbidities with CABG. Multiple arterial grafting was best. In aortic valve surgery, meta-analyses of randomized trials report that transcatheter aortic valve implantation may provide a short-term advantage but long-term survival may be better with classic aortic valve replacement (AVR). Minimally invasive AVR and decellularized homografts emerged as hopeful techniques. In mitral and tricuspid valve surgery, excellent perioperative and long-term outcomes were presented for structural mitral regurgitation. For both, coronary and valve surgery, outcomes are strongly dependent on surgeon expertise. Kidney disease increases perioperative risk, but does not limit the surgical treatment effect. Finally, a cursory look is thrown on aortic, transplant, and assist-device surgery with a glimpse into the current stand of xenotransplantation. As in recent years, this article summarizes publications perceived as important by us. It does not expect to be complete and cannot be free of individual interpretation. We aimed to provide up-to-date information for decision-making and patient information.

Multiple versus single arterial grafting in the elderly: a meta-analysis of randomized controlled trials and propensity score studies

INTRODUCTION

The benefit of adding a second arterial conduit is still controversial, mainly in specific subgroups. We conducted a meta-analysis of randomized controlled trials (RCTs) and propensity score (PS) studies comparing survival and early results in elderly patients who underwent coronary artery bypass grafting (CABG) with multiple (MAG) versus single arterial grafting (SAG).

EVIDENCE ACQUISITION

MEDLINE, Web of Science and Cochrane Library were used to find relevant literature (1960-April 2020). Survival at a ≥ 1-year follow-up and early outcomes were evaluated. Outcomes were collected from matched samples or PS adjusted analysis: hazard ratio (HR) along with their variance, frequencies or odds ratios. Random effect models were used to compute combined statistical measures and 95% confidence intervals (CI) through generic inverse variance method (time-to-event) or Mantel-Haenszel method (binary events).

EVIDENCE SYNTHESIS

Eleven PS cohorts and 1 RCT comprising > 18,800 patients older than 70 (>6200 MAG and >12,500 SAG) were included in this meta-analysis. MAG was associated with lower long-term mortality (pooled HR: 0.81, 95%CI: 0.72-0.91, p<0.01, I2=64%) in the absence of higher risk of early mortality (pooled OR: 0.74, 95%CI: 0.44 to 1.25, p=0.27, I2=0%). In a meta-regression, MAG survival advantage was more pronounced in studies with a higher MAG usage rate (β = -0.0052, p=0.021).

CONCLUSIONS

Current evidence suggests that advanced age should not limit MAG's use considering its benefits in long-term survival. Of note, an individualized patient selection for this approach is warranted.

[Comparative study of vasa vasorum and neointima in conduits for coronary artery bypass grafting]

AIM

This study was undertaken to investigate the preoperative incidence and severity of intimal hypertrophy, as well as the level of blood supply of arterial and venous conduits for coronary artery bypass grafting.

MATERIAL AND METHODS

Segments of the internal thoracic artery and great saphenous vein (n=13) were harvested pairwise during coronary artery bypass grafting and were then visualized by scanning electron microscopy in back-scattered electrons. The analysis of the incidence and thickness of intimal hypertrophy, as well as the calculation of the number and the area of the vasa vasorum were performed using the programme ImageJ.

RESULTS

Intimal hypertrophy was more characteristic for the great saphenous vein as compared with the internal thoracic artery (9/13 (69.2%) and 7/13 (55.8%), respectively), although this difference did not reach statistical significance. The maximal-to-minimal neointimal thickness ratio correlated with the percentage of stenosis (r=0.875, p<0.0001), the area (r=0.45, p=0.023) and the number (r=0.47, p=0.015) of the vasa vasorum in the conduits, thus confirming the hypothesis on possible participation of these vessels in the development of intimal hypertrophy, with the area of the vasa vasorum being greater in the vessels with >10% stenosis (p=0.051). The number of the vasa vasorum in the great saphenous vein exceeded that in the internal thoracic artery (p=0.0005), with this difference remaining significant after adjustment for the area of the adventitia (p=0.027). The number of the vasa vasorum per the percentage of stenosis in the great saphenous vein also exceeded that in the internal thoracic artery (p=0.039) and more strongly correlated with intimal hypertrophy in the great saphenous vein as compared with that in the internal thoracic artery (r=0.53 and r=0.27, respectively).

CONCLUSION

Intimal hypertrophy correlates with the area and number of the vasa vasorum in conduits. The great saphenous vein is characterised by a larger number and higher density of the vasa vasorum as compared with the internal thoracic artery. The number of the vasa vasorum is correlated with stenosis of the great saphenous vein more closely than with stenosis of the internal thoracic artery. This may be suggestive of significant predisposition of the great saphenous vein to the onset of adventitial inflammation followed by the development of intimal hypertrophy.

Measures to Increase Use of Multiple Arterial Grafts for Isolated Coronary Artery Bypass Grafting

BACKGROUND

Use of multiple arterial grafts (MAGs) provides superior patency and long-term survival benefit compared with venous grafts during coronary artery bypass grafting (CABG). However, MAGs are used infrequently for CABG. We hypothesized that specific measures introduced at our institution would lead to an increase in the use of MAGs.

STUDY DESIGN

Use of MAGs before and after introduction of bundled measures was compared. Measures included increased education in arterial graft harvesting, inclusion as a quality metric, and hiring of surgeon champions. Patients younger than 70 years who underwent first time, isolated CABG using at least 1 arterial graft were included. Number and type of grafts used were compared between time periods using chi-square test. Secondary outcomes included postoperative complications. Complications were compared between time periods, as well as between MAG and non-MAG recipients before and after propensity score matching using Fisher exact test and univariate logistic regression. Multivariable logistic regression was used to determine patient characteristics associated with MAG use.

RESULTS

There were 2,169 patients included from 2012 to 2019. MAG use increased significantly after introduction of measures (21.1% to 41.9%; p < 0.001). Radial artery use with an internal mammary artery (0.3% to 16%; p < 0.001) and the use of triple arterial grafts increased significantly (0% to 2.4%; p < 0.001). MAG use in the entire cohort was associated with decreased 30-day mortality and postoperative cardiac arrest that was not significant after propensity matching.

CONCLUSIONS

A programmatic emphasis on the use of MAGs for CABG is an effective method to increase its use.

The RADial artery International ALliance (RADIAL) extended follow-up study: rationale and study protocol

It is generally accepted that radial artery (RA) grafts have better mid-term patency rate compared to saphenous vein grafts. However, the clinical correlates of the improved patency rate are still debated. Observational studies have suggested increased survival and event-free survival for patients who receive an RA rather than a saphenous vein, but they are open to bias and confounders. The only evidence based on randomized data is a pooled meta-analysis of 6 randomized controlled trial comparing the RA and the saphenous vein published by the RADial artery International Alliance (RADIAL). In the RADIAL database, improved freedom from follow-up cardiac events (death, myocardial infarction and repeat revascularization) was found at 5-year follow-up in the RA arm. The most important limitation of the RADIAL analysis is that most of the included trials had an angiographic follow-up in the first 5 years and it is unclear whether the rate of repeat revascularization (the main driver of the composite outcome) was clinically indicated due to per-protocol angiographies. Here, we present the protocol for the long-term analysis of the RADIAL database. By extending the follow-up beyond the 5th postoperative year (all trials except 1 did not have angiographic follow-up beyond 5 years), we aim to provide data on the role of RA in coronary artery bypass surgery with respect to long-term outcomes.

Slow degrading poly(glycerol sebacate) derivatives improve vascular graft remodeling in a rat carotid artery interposition model

Porous synthetic grafts made of poly (glycerol sebacate) (PGS) can transform into autologous vascular conduits in vivo upon degradation of PGS. A long-held doctrine in tissue engineering is the necessity to match degradation of the scaffolds to tissue regeneration. Here, we tested the impact of degradation of PGS and its derivative in an interposition model of rat common carotid artery (CCA). Previous work indicates a complete degradation of PGS within approximately 2 weeks, likely at the fast end of the spectrum. Thus, the derivation of PGS focuses on delay degradation by conjugating the free hydroxy groups in PGS with a long chain carboxylic acid: palmitic acid, one of the most common lipid components. We evaluated two of the resultant palmitate-PGS (PPGS) in this study: one containing 9% palmitate (9-PPGS) and the other16% palmitate (16-PPGS). 16-PPGS grafts had the highest patency. Ultrasound imaging showed that the lumens of 16-PPGS grafts were similar to CCA and smaller than 9-PPGS and PGS grafts 12 weeks post-operation. Immunohistological and histological examination showed an endothelialized lumens in all three types of grafts within 4 weeks. Inflammatory responses to 16-PPGS grafts were limited to the adventitial space in contrast to a more diffusive infiltration in 9-PPGS and PGS grafts in week 4. Examination of calponin+ and αSMA+ cells revealed that 16-PPGS grafts remodeled into a distinctive bi-layered wall, while the walls of 9-PPGS grafts and PGS grafts only had one thick layer of smooth muscle-like cells. Correspondingly, the expression of collagen III and elastin displayed an identical layered structure in the remodeled 16-PPGS grafts, in contrast to a more spread distribution in 9-PPGS and PGS grafts. All the three types of grafts exhibited the same collagen content and burst pressure after 12 weeks of host remodeling. However, the compliance and elastin content of 16-PPGS grafts in week 12 were closest to those of CCA. Overall, placing the degradation of PGS derived elastomer to a window of 4-12 weeks results in vascular conduits closer to arteries in a rat carotid artery interposition model over a 12-week observation period.

Association of Radial Artery Graft vs Saphenous Vein Graft With Long-term Cardiovascular Outcomes Among Patients Undergoing Coronary Artery Bypass Grafting: A Systematic Review and Meta-analysis

IMPORTANCE

Observational studies have suggested that the use of radial artery grafts for coronary artery bypass grafting may improve clinical outcomes compared with the use of saphenous vein grafts, but this has not been confirmed in randomized trials.

OBJECTIVE

To compare clinical outcomes between patients receiving radial artery vs saphenous vein grafts for coronary artery bypass grafting after long-term follow-up.

DESIGN, SETTING, AND PARTICIPANTS

Patient-level pooled analysis comparing radial artery vs saphenous vein graft in adult patients undergoing isolated coronary artery bypass grafting from 5 countries (Australia, Italy, Serbia, South Korea, and the United Kingdom), with enrollment from 1997 to 2009 and follow-up completed in 2019.

INTERVENTIONS

Patients were randomized to undergo either radial artery (n = 534) or saphenous vein (n = 502) grafts for coronary artery bypass grafting.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of death, myocardial infarction, or repeat revascularization and the secondary outcome was a composite of death or myocardial infarction.

RESULTS

A total of 1036 patients were randomized (mean age, 66.6 years in the radial artery group vs 67.1 years in the saphenous vein group; 376 [70.4%] men in the radial artery group vs 351 [69.9%] in the saphenous vein group); 942 (90.9%) of the originally randomized patients completed 10 years of follow-up (510 in the radial artery group). At a median (interquartile range) follow-up of 10 (10-11) years, the use of the radial artery, compared with the saphenous vein, in coronary artery bypass grafting was associated with a statistically significant reduction in the incidence of the composite outcome of death, myocardial infarction, or repeat revascularization (220 vs 237 total events; 41 vs 47 events per 1000 patient-years; hazard ratio, 0.73 [95% CI, 0.61-0.88]; P < .001) and of the composite of death or myocardial infarction (188 vs 193 total events; 35 vs 38 events per 1000 patient-years; hazard ratio, 0.77 [95% CI, 0.63-0.94]; P = .01).

CONCLUSIONS AND RELEVANCE

In this individual participant data meta-analysis with a median follow-up of 10 years, among patients undergoing coronary artery bypass grafting, the use of the radial artery compared with the saphenous vein was associated with a lower risk of a composite of cardiovascular outcomes.

Sex differences after coronary artery bypass grafting with a second arterial conduit

OBJECTIVES

Double arterial conduit use during coronary artery bypass grafting is associated with improved clinical outcomes compared with single arterial conduits in the general population. However, the sex-specific outcomes of this strategy remain unknown and are needed to inform sex-specific revascularization guidelines.

METHODS

We conducted a population-based, retrospective cohort study of all Ontarians who underwent primary isolated coronary artery bypass grafting with single arterial conduits or double arterial conduits between October 2008 and September 2017. The primary outcome was all-cause mortality. Secondary outcomes included major adverse cardiac and cerebrovascular events, defined as a composite of myocardial infarction, heart failure hospitalization, repeat revascularization, and stroke. We used inverse probability of treatment weighting to account for group imbalances.

RESULTS

A total of 9135 women and 36,748 men underwent coronary artery bypass grafting. At 30 days, there was no between-group difference in mortality or major adverse cardiac and cerebrovascular events in men. However, among women, a double arterial conduit was associated with an increased rate of 30-day death (hazard ratio, 1.48; 95% confidence interval, 1.23-1.79) and major adverse cardiac and cerebrovascular events (hazard ratio, 1.32; 95% confidence interval, 1.14-1.51). The risk of medium-term mortality with double arterial conduits was less in men (hazard ratio, 0.88; 95% confidence interval, 0.84-0.92) and women (hazard ratio, 0.87; 95% confidence interval, 0.81-0.94), as was the medium-term risk of major adverse cardiac and cerebrovascular events (hazard ratio, 0.91; 95% confidence interval, 0.87-0.94) [men]; hazard ratio, 0.91; 95% confidence interval, 0.86-0.97) [women]). The incremental improvement in 9-year survival was 4.0% in women with a double arterial conduit and 0.9% in men.

CONCLUSIONS

Double arterial conduit is associated with better medium-term survival and cardiovascular outcomes in both sexes. Double arterial conduits are associated with increased perioperative risk in women, but the medium-term benefit is greater than in men.

Is the result of modified Allen’s test still accurate after endoscopic thoracic sympathectomy?

Background

The radial artery (RA) is increasingly being used for coronary artery bypass grafting (CABG). Endoscopic thoracic sympathectomy (ETS) has been shown to block innervation of sympathetic nerves of upper limbs, which reduces sweating of hands and dilates blood vessels. The modified Allen’s test (MAT) is one of the commonest methods of assessing collateral arm flow prior to RA harvest, though it has limitations. However, the reliability of MAT after ETS remains unclear. We therefore investigated the effects of ETS on the results of MAT.

Methods

A retrospective cohort study was conducted on 164 consecutive Chinese patients with palmar hyperhidrosis who underwent ETS between January 2016 and January 2019. The medical records were reviewed concerning the ultrasound examination and MAT results of their RAs and ulnar arteries (UAs) in both forearms before and after ETS.

Results

The performance of ETS significantly increased the diameter of the right RA from 2.731±0.122 to 3.102±0.114 mm in men and from 2.347±0.074 to 2.915±0.162 mm in women. Similar effects of ETS were observed in expanding the diameters of the left RA and the UA. Meanwhile, there was no significant effect of ETS on systolic blood pressure (BP) and heart rate (HR). Overall, retesting of patients following ETS with a preoperative positive MAT result revealed a transition to a negative result.

Conclusions

ETS was effective in dilating RA in both men and women, which could lead to a false negative preoperative MAT result. Patients should be questioned about their history of ETS if their RAs are to be harvested for CABG. More studies are warranted to evaluate the safety of RA as a coronary artery graft after ETS.

Endoscopic Radial Artery Harvesting During Anesthesia Line Placement Reduces the Time and Cost of Multivessel Coronary Artery Bypass Grafting

Objective

Endoscopic radial artery (RA) harvesting performed concurrently with internal mammary artery (IMA) takedown and endoscopic saphenous vein (SV) harvesting creates a crowded and inefficient operating room environment. We assessed the effect of a presternotomy RA harvest strategy on surgery time and costs.

Methods

A total of 41 patients underwent elective, first-time, isolated multivessel on-pump coronary artery bypass grafting including an IMA, RA, and SV graft. The first 20 patients (Phase I) underwent endoscopic RA harvesting concurrently with IMA takedown and endoscopic SV harvesting after sternotomy, requiring two sets of endoscopic harvesting equipment per case, each used by a separate individual. The final 21 patients (Phase II) underwent endoscopic RA harvesting during anesthesia line placement, completing the procedure before sternotomy, thus requiring only one set of endoscopic harvesting equipment reused by a single individual.

Results

There were no differences in baseline patient characteristics, number of bypasses, duration of SV or RA harvest time, or duration of cardiopulmonary bypass or cross-clamp time between the two groups. Total surgery time was reduced by 32 minutes in Phase II ( P = 0.044). Relative to a total hospital direct cost of 100.00 units, total surgery costs were reduced from 29.33 units in Phase I to 25.62 units in Phase II ( P = 0.001). No anesthesia- or RA harvest-related complications occurred in either group.

Conclusions

Endoscopic RA harvesting can be safely performed during anesthesia line placement prior to sternotomy. Our simple but innovative strategy improves intraoperative workflow, reduces the time and cost of surgery, and advances the delivery of high-quality patient care.

Arterial Grafts for Coronary Bypass

Observational and randomized evidence shows that arterial grafts have better patency rates than saphenous vein grafts (SVGs) in coronary artery bypass grafting. Observational studies suggest that the use of multiple arterial grafts is associated with longer postoperative survival, but this must be interpreted in the context of treatment allocation bias and hidden confounders intrinsic to the study designs. Recently, a pooled analysis of 6 randomized trials comparing the radial artery with the SVG as the second conduit and the largest randomized trial comparing the use of single and bilateral internal thoracic arteries have provided apparently divergent results about a clinical benefit with the use of >1 arterial conduit. However, both analyses have methodological limitations that may have influenced their results. At present, it is unclear whether the well-documented increased patency rate of arterial grafts translates into clinical benefits in the majority of patients undergoing coronary artery bypass grafting. A large randomized trial testing the arterial grafts hypothesis (ROMA [Randomized Comparison of the Clinical Outcome of Single Versus Multiple Arterial Grafts]) is underway and will report the results in a few years.

Multiarterial coronary artery bypass grafting: is the radial artery fulfilling the unkept promise of the right internal thoracic artery?

PURPOSE OF REVIEW

The debate on the second best conduit for CABG is still intense. In this review, we discuss the role of the radial artery and the right internal thoracic artery (RITA) compared with saphenous vein grafts (SVG).

RECENT FINDINGS

The recent RADIAL STUDY has been the first evidence based on randomized trials of a clinical benefit using a second arterial graft in CABG.On the other hand, the definitive 10-year results of the ART trial failed to show a clinical advantage associated with the use of bilateral internal thoracic artery (BITA). A thorough and contextualized analysis of this and other studies, however, may offer a different perspective.

SUMMARY

Arterial conduits in CABG have shown better patency rates than SVG. Whether this leads to better clinical outcomes is still debated. In this setting, the radial artery and the RITA seem to offer a similar advantage, although with different indications and contraindications.

Right internal thoracic or radial artery as the second arterial conduit for coronary artery bypass surgery

PURPOSE OF REVIEW

To summarize the available evidence on the use of the right internal thoracic artery (RITA) and the radial artery as the second arterial graft in coronary artery bypass surgery.

RECENT FINDINGS

The current data support the equipoise of the two conduits in terms of clinical and angiographic outcomes. Both RITA and radial artery have better patency than saphenous vein grafts. The use of the RITA carries an increased risk of deep sternal wound infection (DSWI) if the artery is harvested as pedicle. Bilateral internal thoracic artery grafting is more technically demanding than radial artery use and there is a volume-outcome relationship in terms of mortality and incidence of DSWI. The radial artery is preferable over RITA in right-sided or distal circumflex artery targets with high-degree stenosis and in patients at higher risk for DSWI, whereas it is not recommended to graft vessels with moderate stenosis and in cases of insufficient collateralization from the ulnar artery or previous transradial procedures.

SUMMARY

The patency rate and clinical outcomes of radial artery and RITA are similar. The use of one or the other should be based on a careful evaluation of the patient's coronary anatomy and comorbidities, the conduit availability and the surgeon's and center's experience.