Intermediate-Term Outcomes of Endoscopic or Open Vein Harvesting for Coronary Artery Bypass Grafting: The REGROUP Randomized Clinical Trial

Unplanned postoperative catheterization during admission for coronary artery bypass grafting is neither cheap nor benign, but may rescue patients

OBJECTIVE

Literature describing outcomes of myocardial ischemia after coronary artery bypass grafting is sparse. We hypothesized these patients had more complications and incurred higher costs of care.

METHODS

Using adult cardiac surgery data and cardiac catheterization (CathPCI) data from the Virginia Cardiac Services Quality Initiative, we identified patients who underwent unplanned cardiac catheterization after coronary artery bypass grafting from 2018 to 2021. Adult cardiac surgery data were matched to CathPCI data examining earliest in-hospital catheterization. Patients not requiring catheterization served as the control group.

RESULTS

We identified 10,597 patients who underwent isolated coronary artery bypass grafting, of whom 41 of 10,597 underwent unplanned cardiac catheterization. A total of 21 of 41 patients (51%) received percutaneous coronary intervention, most commonly for non-ST-elevation myocardial infarction (n = 7, 33%) and ST-elevation myocardial infarction (n = 6, 29%). Postoperative cardiac arrest occurred in 14 patients (40%). In patients who underwent percutaneous coronary intervention, 14 (67%) had a single lesion, 4 (19%) had 2 lesions, and 3 (14%) had 3 lesions. The left anterior descending artery (38%) was the most frequently intervened upon vessel. Patients who underwent catheterization were more likely to require balloon pump support (26% vs 11%), to have prolonged ventilation (57% vs 20%), to have renal failure (17% vs 7.1%), and to undergo reintubation (37% vs 3.8%, all P < .04). There was no statistical difference in operative mortality (4.9% vs 2.3%, P = .2) or failure to rescue (4.9% vs 1.6%, P = .14). Total costs were higher in patients who underwent unplanned catheterization ($81,293 vs $37,011, P < .001).

CONCLUSIONS

Unplanned catheterization after coronary artery bypass grafting is infrequent but associated with more complications and a higher cost of care. Therefore, determination of an association with operative mortality in patients with suspected ischemia after coronary artery bypass grafting requires additional study.

Chronic total occlusions and coronary artery bypass grafting outcomes

OBJECTIVE

To investigate the association between the presence and grafting of chronic total occlusions (CTOs) and coronary artery bypass grafting (CABG) outcomes.

METHODS

This was a post hoc analysis of the Randomized Endograft vs Open Prospective (REGROUP) trial, which randomized veterans undergoing isolated on-pump CABG to endoscopic versus open vein harvest (2014-2017). Patients were stratified on the basis of the presence of at least 1 CTO vessel (a 100% occluded coronary lesion for greater than or equal to 3 months) and according to whether all CTO vessels were bypassed. Rates of major cardiac adverse events (MACE) were compared.

RESULTS

At least 1 CTO was present in 453 of 1149 patients (39.4%). Over a median follow-up of 4.7 years (interquartile range, 3.84-5.45), MACE rates were 23.4% versus 22.2% for the CTO versus no CTO group, respectively (adjusted hazard ratio [aHR], 0.92; 95% confidence interval [CI], 0.70-1.20). MACE rates for patients with complete CTO grafting versus not were 23.1% versus 25.0%, respectively (aHR, 0.95; 95% CI, 0.57-1.57). In patients with right coronary dominance undergoing left anterior descending artery grafting, bypassing a right coronary artery CTO was associated with significantly lower rates of all-cause mortality (aHR, 0.38; 95% CI, 0.17-0.83).

CONCLUSIONS

In this REGROUP trial subanalysis, neither CTO presence or complete grafting of CTO vessels was associated with significantly different rates of MACE. However, the finding of possible survival benefit among a subgroup of patients undergoing grafting of a dominant RCA CTO vessel alongside left anterior descending artery grafting warrants additional study.

An Obligatory Role of Perivascular Adipose Tissue in Improved Saphenous Vein Graft Patency in Coronary Artery Bypass Grafting

The gold standard graft for coronary artery bypass grafting (CABG) is the internal thoracic artery (ITA), and the second recommendation is the radial artery. However, complete revascularization with arterial grafts alone is often difficult, and the saphenous vein (SV) is the most commonly used autologous graft for CABG, because it is easier to use without restriction for the length of the graft. On the other hand, the patency of SV grafts (SVGs) is poor compared with that of arterial grafts. The SVG is conventionally harvested as a distended conduit with surrounding tissue removed, a procedure that may cause vascular damage. A no-touch technique of SVG harvesting has been reported to result in improved long-term patency in CABG comparable to that when using the ITA for grafting. Possible reasons for the excellent long-term patency of no-touch SVGs are the physical support provided by preserved surrounding perivascular adipose tissue, preservation of the vascular wall structure including the vasa vasorum, and production of adipocyte-derived factors. In this review, we discuss recent strategies aimed at improving the performance of SVGs, including no-touch harvesting, minimally invasive harvesting and mechanical support using external stents.

Complete Coronary Revascularization and Outcomes in Patients Who Underwent Coronary Artery Bypass Grafting: Insights from The REGROUP Trial

There is growing evidence in support of coronary complete revascularization (CR). Nonetheless, there is no universally accepted definition of CR in patients who undergo coronary bypass grafting surgery (CABG). We sought to investigate the outcomes of CR, defined as surgical revascularization of any territory supplied by a suitable coronary artery with ≥50% stenosis. We performed a preplanned subanalysis in the Randomized Trial of Endoscopic or Open Saphenous Vein Graft Harvesting (REGROUP) clinical trial cohort. Of 1,147 patients who underwent CABG, 810 (70.6%) received CR. The primary outcome was a composite of major adverse cardiac events (MACEs), including death from any cause, nonfatal myocardial infarction, or repeat revascularization over a median 4.7 years of follow-up. MACE occurred in 175 patients (21.6%) in the CR group and 86 patients (25.5%) in the incomplete revascularization (IR) group (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.67 to 1.13, p = 0.29). A total of 97 patients (12.0%) in the CR group and 48 patients (14.2%) in the IR group died (HR 0.93, 95% CI 0.65 to 1.32, p = 0.67); nonfatal myocardial infarction occurred in 49 patients (6.0%) in the CR group and 30 patients (8.9%) in the IR group (HR 0.76, 95% CI 0.48 to 1.2, p = 0.24), and repeat revascularization occurred in 62 patients (7.7%) in the CR group and 39 patients (11.6%) in the IR group (HR 0.64; 95% CI 0.42 to 0.95, p = 0.027). In conclusion, in patients with a great burden of co-morbidities who underwent CABG in the REGROUP trial over a median follow-up period of a median 4.7 years, CR was associated with similar MACE rates but a reduced risk of repeat revascularization. Longer-term follow-up is warranted.

Impact of Oral Anticoagulation on Clinical Outcomes in Postoperative Atrial Fibrillation

INTRODUCTION

The impact of postoperative oral anticoagulation (OAC) with warfarin on postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) was the focus of this examination of patients from the randomized endo-vein graft prospective (REGROUP) Trial.

MATERIAL AND METHODS

REGROUP was a prospective randomized Veterans Affairs cooperative study comparing endoscopic versus open vein harvest in elective CABG patients (March 2014-April 2017) at 16 Veterans Affairs facilities. This study compared new-onset POAF patients who were treated with warfarin versus no-warfarin. Outcomes included stroke during active follow-up and a major adverse cardiac event composite of mortality, acute myocardial infarction, and repeat revascularization during active and passive follow-up.

RESULTS

Of the 316/1103 (28.6%) of REGROUP patients who developed new-onset POAF, 45 patients were excluded - mainly for preoperative warfarin use. Of the remaining 269 patients, 85 received OAC with warfarin (OAC group); 184 did not (no-OAC group). Stroke rates during active follow-up (32 [IQR 24-38] mo) were 3.5% OAC group versus 5.4% no-OAC group (P = 0.76); major adverse cardiac eventrates were 20% OAC versus 11.4% no-OAC (P = 0.06). On longer follow-up of (median 4.61 [IQR 3.9-5.1] y), discharge OAC use was associated with all-cause mortality after adjusting for Society of Thoracic Surgeons mortality risk (20.0% versus 11.4% no-OAC use; HR = 2.00, 95% CI: 1.05-3.81, P = 0.035).

CONCLUSIONS

REGROUP patients with POAF treated with OAC had similar stroke and higher mortality rates versus no-OAC patients. Further investigation of the risk-benefit ratio of OAC in post-CABG patients and which POAF patient subgroups might derive the most benefit with anticoagulation appears warranted.

Consensus statement-graft treatment in cardiovascular bypass graft surgery

Coronary artery bypass grafting (CABG) is and continues to be the preferred revascularization strategy in patients with multivessel disease. Graft selection has been shown to influence the outcomes following CABG. During the last almost 60 years saphenous vein grafts (SVG) together with the internal mammary artery have become the standard of care for patients undergoing CABG surgery. While there is little doubt about the benefits, the patency rates are constantly under debate. Despite its acknowledged limitations in terms of long-term patency due to intimal hyperplasia, the saphenous vein is still the most often used graft. Although reendothelialization occurs early postoperatively, the process of intimal hyperplasia remains irreversible. This is due in part to the persistence of high shear forces, the chronic localized inflammatory response, and the partial dysfunctionality of the regenerated endothelium. "No-Touch" harvesting techniques, specific storage solutions, pressure controlled graft flushing and external stenting are important and established methods aiming to overcome the process of intimal hyperplasia at different time levels. Still despite the known evidence these methods are not standard everywhere. The use of arterial grafts is another strategy to address the inferior SVG patency rates and to perform CABG with total arterial revascularization. Composite grafting, pharmacological agents as well as latest minimal invasive techniques aim in the same direction. To give guide and set standards all graft related topics for CABG are presented in this expert opinion document on graft treatment.

Techniques and Technologies to Improve Vein Graft Patency in Coronary Surgery

Vein grafts are the most used conduits in coronary artery bypass grafting (CABG), even though many studies have suggested their lower patency compared to arterial alternatives. We have reviewed the techniques and technologies that have been investigated over the years with the aim of improving the quality of these conduits. We found that preoperative and postoperative optimal medical therapy and no-touch harvesting techniques have the strongest evidence for optimizing vein graft patency. On the other hand, the use of venous external support, endoscopic harvesting, vein preservation solution and anastomosis, and graft configuration need further investigation. We have also analyzed strategies to treat vein graft failure: when feasible, re-doing the CABG and native vessel primary coronary intervention (PCI) are the best options, followed by percutaneous procedures targeting the failed grafts.

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).

Endoscopic vs Open Vein Harvest in Drug-Eluting Stents or Bypass Surgery for Left Main Disease Trial

BACKGROUND

We investigated outcomes of coronary artery bypass grafting (CABG) with endoscopic vein harvest (EVH) vs open vein harvest (OVH) within the Evaluation of XIENCE Versus CABG (EXCEL) trial.

METHODS

All patients in EXCEL randomized to CABG were included in this study. For this analysis, the primary end points were ischemia-driven revascularization (IDR) and graft stenosis or occlusion at 5 years. Additional end points were as follows: a composite of death from any cause, stroke, or myocardial infarction; bleeding; blood product transfusion; major arrhythmia; and infection requiring antibiotics. Event rates were based on Kaplan-Meier estimates in time-to-first-event analyses.

RESULTS

Of the 957 patients randomized to CABG, 686 (71.7%) received at least 1 venous graft with 257 (37.5%) patients in the EVH group and 429 (62.5%) patients in the OVH group. At 5 years, IDR was higher (11.5% vs 6.7%; P = .047) in the EVH group. At 5 years, rates of graft stenosis or occlusion (9.7% vs 5.4%; P = .054) and the primary end point (17.4% vs 20.9%; P = .27) were similar. In-hospital bleeding (11.3% vs 13.8%; P = .35), in-hospital blood product transfusion (12.8% vs 13.1%; P = .94), and infection requiring antibiotics within 1 month (13.6% vs 16.8%; P = .27) were similar between EVH and OVH patients. Major arrhythmia in the hospital (19.8% vs 13.5%; P = .03) and within 1 month (21.8% vs 15.4%; P = .03) was higher in EVH patients.

CONCLUSIONS

IDR at 5 years was higher in the EVH group. EVH and OVH patients had similar rates of graft stenosis or occlusion and the composite of death, stroke, or myocardial infarction at 5 years.

Effects of the harvesting technique and external stenting on progression of vein graft disease 2 years after coronary artery bypass

OBJECTIVES

In a post hoc analysis of the VEST III trial, we investigated the effect of the harvesting technique on saphenous vein graft (SVG) patency and disease progression after coronary artery bypass grafting.

METHODS

Angiographic outcomes were assessed in 183 patients undergoing open (126 patients, 252 SVG) or endoscopic harvesting (57 patients, 114 SVG). Overall SVG patency was assessed by computed tomography angiography at 6 months and by coronary angiography at 2 years. Fitzgibbon patency (FP I, II and III) and intimal hyperplasia (IH) in a patient subset were assessed by coronary angiography and intravascular ultrasound, respectively, at 2 years.

RESULTS

Baseline characteristics were similar between patients who underwent open and those who underwent endoscopic harvesting. Open compared with endoscopic harvesting was associated with higher overall SVG patency rates at 6 months (92.9% vs 80.4%, P = 0.04) and 2 years (90.8% vs 73.9%, P = 0.01), improved FP I, II and III rates (65.2% vs 49.2%; 25.3% vs 45.9%, and 9.5% vs 4.9%, respectively; odds ratio 2.81, P = 0.09) and reduced IH area (-31.8%; P = 0.04) and thickness (-28.9%; P = 0.04). External stenting was associated with improved FP I, II and III rates (odds ratio 2.84, P = 0.01), reduced IH area (-19.5%; P < 0.001) and thickness (-25.0%; P < 0.001) in the open-harvest group and reduced IH area (-12.7%; P = 0.01) and thickness (-9.5%; P = 0.21) in the endoscopic-harvest group.

CONCLUSIONS

A post-hoc analysis of the VEST III trial showed that open harvesting is associated with improved overall SVG patency and reduced IH. External stenting reduces SVG disease progression, particularly with open harvesting.

Costs of Endoscopic vs Open Vein Harvesting for Coronary Artery Bypass Grafting: A Secondary Analysis of the REGROUP Trial

IMPORTANCE

Value-based purchasing creates pressure to examine whether newer technologies and care processes, including new surgical techniques, yield any economic advantage.

OBJECTIVE

To compare health care costs and utilization between participants randomized to receive endoscopic vein harvesting (EVH) or open vein harvesting (OVH) during a coronary artery bypass grafting (CABG) procedure.

DESIGN, SETTING, AND PARTICIPANTS

This secondary economic analysis was conducted alongside the 16-site Randomized Endo-Vein Graft Prospective (REGROUP) clinical trial funded by the Department of Veterans Affairs (VA) Cooperative Studies Program. Adults scheduled for urgent or elective bypass involving a vein graft were eligible. The first participant was enrolled in September 2013, with most sites completing enrollment by March 2014. The last participant was enrolled in April 2017. A total of 1150 participants were randomized, with 574 participants receiving OVH and 576 receiving EVH. For this secondary analysis, cost and utilization data were extracted through September 30, 2020. Participants were linked to administrative data in the VA Corporate Data Warehouse and activity-based cost data starting with the index procedure.

INTERVENTIONS

EVH vs OVH, with comparisons based on intention to treat.

MAIN OUTCOMES AND MEASURES

Discharge costs for the index procedure as well as follow-up costs (including intended and unintended events; mean [SD] follow-up time, 33.0 [19.9] months) were analyzed, with results from different statistical models compared to test for robustness (ie, lack of variation across models). All costs represented care provided or paid by the VA, standardized to 2020 US dollars.

RESULTS

Among 1150 participants, the mean (SD) age was 66.4 (6.9) years; most participants (1144 [99.5%] were male. With regard to race and ethnicity, 6 participants (0.5%) self-reported as American Indian or Alaska Native, 10 (0.9%) as Asian or Pacific Islander, 91 (7.9%) as Black, 62 (5.4%) as Hispanic, 974 (84.7%) as non-Hispanic White, and 6 (0.5%) as other race and/or ethnicity; data were missing for 1 participant (0.1%). The unadjusted mean (SD) costs for the index CABG procedure were $76 607 ($43 883) among patients who received EVH and $75 368 ($45 900) among those who received OVH, including facility costs, insurance costs, and physician-related costs (commonly referred to as provider costs in Centers for Medicare and Medicaid and insurance data). No significant differences were found in follow-up costs; per 90-day follow-up period, EVH was associated with a mean (SE) added cost of $302 ($225) per patient. The results were highly robust to the statistical model.

CONCLUSIONS AND RELEVANCE

In this study, EVH was not associated with a reduction in costs for the index CABG procedure or follow-up care. Therefore, the choice to provide EVH may be based on surgeon and patient preferences.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01850082.

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.

Clinical trials proposed for the VA Cooperative Studies Program: Success rates and factors impacting approval

The process by which funding organizations select among the myriad number of proposals they receive is a matter of significant concern for researchers and the public alike. Despite an extensive literature on the topic of peer review and publications on criteria by which clinical investigations are reviewed, publications analyzing peer review and other processes leading to government funding decisions on large multi-site clinical trials proposals are sparse. To partially address this gap, we reviewed the outcomes of scientific and programmatic evaluation for all letters of intent (LOIs) received by the Department of Veterans Affairs (VA) Cooperative Studies Program (CSP) between July 4, 2008, and November 28, 2016. If accepted, these LOIs represented initial steps towards later full proposals that also underwent scientific peer review. Twenty-two of 87 LOIs were ultimately funded and executed as CSP projects, for an overall success rate of 25%. Most proposals which received a negative decision did so prior to submission of a full proposal. Common reasons for negative scientific review of LOIs included investigator inexperience, perceived lack of major scientific impact, lack of preliminary data and flawed or confused experimental design, while the most common reasons for negative reviews of final proposals included questions of scientific impact and issues of study design, including outcome measures, randomization, and stratification. Completed projects have been published in high impact clinical journals. Findings highlight several factors leading to successfully obtaining funding support for clinical trials. While our analysis is restricted to trials proposed for CSP, the similarities in review processes with those employed by the National Institutes of Health and the Patient Centered Outcomes Research Institute suggest the possibility that they may also be important in a broader context.

A multicentre review comparing long term outcomes of endoscopic vein harvesting versus open vein harvesting for coronary artery bypass surgery

Background

Utilisation of the Endoscopic Vein Harvesting (EVH) technique has been increasing for coronary artery bypass grafting (CABG) for the last two decades. Some surgeons remain concerned about the long-term patency of the long saphenous vein harvested endoscopically compared to traditional Open Vein Harvesting (OVH). The aim of this study was to perform a retrospective analysis of the outcomes between EVH and OVH from three UK centres with 10 years follow-up.

Methods

27,024 patients underwent CABG with long saphenous vein harvested by EVH (n=13,794) or OVH (n=13,230) in three UK centres between 2007 and 2019. Propensity modelling was used to calculate the Inverse Probability of Treatment Weights (IPTW). The primary endpoint was mortality from all causes and secondary endpoints were length of hospital stay, postoperative complications, and incidence of repeat coronary re-vascularisation for symptomatic patients. IPTW was used to balance the two intervention groups for baseline and preoperative co-morbidities.

Results

Median follow-up time was 4.54 years for EVH and 6.00 years for OVH. Death from any cause occurred in 13.8% of the EVH group versus 20.8% in the OVH group over the follow-up period. The hazard ratio of death (EVH to OVH) was 0.823 (95% CI: 0.767, 0.884). Length of hospital stay was similar between the groups (p=0.86). Post-operative pulmonary complications were more common in EVH vs OVH (14.7% vs. 12.8%, p<0.001), but repeat coronary re-vascularisation was similar between the groups.

Conclusions

This large retrospective multicentre analysis indicates that EVH has a lower risk of mortality compared with OVH during the follow-up period of the study. The observed benefits of EVH may outweigh the risks but should be considered on a case-by-case basis. We hope this review gives confidence to other cardiac centres that offering an EVH approach to conduit harvesting does not affect long term patient outcomes.