Five-Year Outcomes after Off-Pump or On-Pump Coronary-Artery Bypass Grafting

Early and Long-Term Outcomes after On-Pump and Off-Pump Coronary-Artery Bypass Grafting in Patients with Severe Left Ventricular Dysfunction and a Giant Left Ventricle

Introduction: No previous studies comparing the outcomes between off-pump coronary artery bypass grafting (off-pump CABG, OPCAB) and on-pump CABG (ONCAB) have been performed in patients with severe left ventricular dysfunction (LVD) and a giant left ventricle. We aimed to investigate whether such patients could benefit from OPCAB. Methods: From January 2011 to January 2021, a total of 98 patients with severe LVD and a giant left ventricle underwent isolated CABG (ONCAB 46, OPCAB 52) in Wuhan Union Hospital. The clinical data were collected retrospectively and propensity score matching was performed to adjust baseline characteristics. Results: After propensity matching, the two groups were comparable in baseline variables. The OPCAB group had a higher rate of incomplete revascularization than the ONCAB group (25.0% vs. 9.1%; p = 0.047). The 30-day mortality was similar between the matched groups (4.5% vs. 4.5%; p = 1.000) but the OPCAB group had a lower risk of postoperative IABP usage (9.1% vs. 25.0%; p = 0.047) and renal insufficiency (11.4% vs. 29.5%; p = 0.034). The long-term probability of survival (log-rank test, p = 0.450) was similar between the two groups but the OPCAB group had a lower probability of major adverse cardiovascular events (log-rank test, p = 0.038). Conclusions: For patients with severe LVD and a giant left ventricle, OPCAB reduced early postoperative complications while sacrificing long-term quality of life compared to those having ONCAB.

An overlap-weighted analysis on 10-year survival of off-pump versus on-pump coronary artery grafting in multivessel coronary artery disease

BACKGROUND AND OBJECTIVE

The introduction of off-pump coronary artery bypass surgery intended to overcome some of the conventional on-pump procedure limitations by avoiding potentially harmful adverse effects of extracorporeal circulation and aortic cross-clamping. However, the doubt remains on whether it is associated with worse long-term outcomes. To compare long-term survival in patients with multivessel ischemic heart disease undergoing off-pump versus on-pump coronary artery bypass grafting.

METHODS

Retrospective analysis of 4788 consecutive patients undergoing primary isolated multivessel coronary artery bypass grafting surgery, performed from 2000 to 2015, in Northern Portugal. Among the study population, we identified 1616 and 3172 patients that underwent off-pump and on-pump coronary artery grafting, respectively. We employed a propensity-score-based overlap weighting (OW) algorithm to restrict confounding by indication. The primary endpoint was all-cause mortality at 10 years.

RESULTS

The mean age of the study population was 63.9 (±9.8) years, and 951 (19.9%) were females. OW was effective in eliminating differences in all major baseline characteristics. Follow-up was 100% complete. The median follow-up time was 12.80 (9.62, 16.62) years. The primary endpoint of all-cause mortality at 10 years occurred in 431 patients (26.7%) in the off-pump group, as compared with 863 (27.2%) in the on-pump group (hazard ratio, 0.93; 95% confidence interval, 0.83-1.04; p = .196).

CONCLUSIONS

In this longitudinal, population-level comparison of off-pump versus on-pump coronary artery bypass surgery for treating multivessel coronary artery disease, the primary outcome of long-term mortality was identical among both patients' groups.

Off-pump or on-pump coronary artery bypass at 30 days: A propensity matched analysis

Introduction

This study was to determine whether coronary artery bypass grafting without cardiopulmonary bypass (off-pump CABG, OPCAB) could reduce early postoperative mortality and major complications compared with conventional coronary artery bypass grafting with cardiopulmonary bypass (on-pump CABG, ONCAB) by experienced surgeons.

Material and methods

From January 2016 to June 2020, isolated CABG was performed in 1200 patients (ONCAB 429, OPCAB 771) in Wuhan Union Hospital. The propensity score matching was used to adjust for differences in baseline characteristics between the ONCABG and OPCABG groups. After 1:1 matching, 404 pairs for each group were selected to compare outcomes within 30 days after surgery. All the operations were completed by experienced surgeons that had completed more than 500 on-pump and 200 off-pump CABG, respectively.

Results

After propensity matching, the two groups were comparable in terms of preoperative characteristics. The OPCAB group had less vein graft (2.5 ± 1.0 vs. 2.7 ± 0.9; P < 0.001) and a higher rate of incomplete revascularization (12.4 vs. 8.2%; P < 0.049) than the ONCAB group. There was no significant difference in early postoperative mortality between ONCAB and OPCAB groups (2.2 vs. 2.2%; P = 1.00). However, patients in the OPCAB group had a lower risk of postoperative stroke (1.5 vs. 4.7%; P = 0.008), new-onset renal insufficiency (8.9 vs. 18.8%; P < 0.001), respiratory failure (2.2 vs. 7.2%; P = 0.001), reoperation for bleeding (0.5 vs. 2.7%; P = 0.001), and required less ventilator assistance time (33.4 ± 37.9 h vs. 51.0 ± 66.1 h; P < 0.001) and intensive care unit (ICU) time (3.7 ± 2.7 days vs. 4.8 ± 4.3 days; P < 0.001).

Conclusions

In our study, patients undergoing OPCAB had fewer postoperative complications and a faster recovery. It is a feasible and safe surgical approach to achieve revascularization when performed by experienced surgeons.

Revascularization strategies for patients with established chronic coronary syndrome

Coronary artery disease is the most common type of cardiovascular disease, leading to high mortality rates worldwide. Although the vast majority can be treated effectively and safely by medical therapy, revascularization strategies remain essential for numerous patients. Outcomes of both percutaneous coronary intervention and coronary artery bypass grafting improve in a rapid pace, resulting from technical innovation and ongoing research. Progress has been achieved by technical improvements in coronary stents, optimal coronary target and graft selection, and the availability of minimally invasive surgical strategies. Besides technical progress, evidence-based patient-tailored decision-making by the Heart Team is the basic precondition for optimal outcome. The combination of fast innovation and long-term clinical evaluations creates a dynamic field. Research outcomes should be carefully interpreted according to the techniques used and the trial's design. Therefore, more and more trial outcomes suggest that revascularization strategies should be tailored towards the specific patient. Although the European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines on myocardial revascularization date from 2018 and a large variety of trial outcomes on revascularization strategies in chronic coronary syndrome have been published since, we aim to provide an updated overview within this review.

Risk factors for cerebrovascular accident after isolated coronary artery bypass grafting in Veterans

BACKGROUND

Cerebrovascular accident (CVA) after coronary artery bypass grafting (CABG) is a devastating complication. Patient comorbidities and intraoperative elements contribute to the risk of CVA. The aim of this study is to identify risk factors for CVA in Veterans undergoing CABG.

METHODS

Veterans undergoing isolated CABG from 2008 to 2019 were retrospectively identified using the Veterans Affairs Surgical Quality Improvement Program (VASQIP) database. Thirty-day postoperative outcomes were observed. Univariate analysis followed by multivariable logistic regression identified independent risk factors for postoperative CVA. Receiver operating characteristic diagnostics identified optimal inflection points between continuous risk factors and odds of CVA.

RESULTS

Twenty-eight thousand seven hundred fifty-seven patients met inclusion criteria. Incidence of CVA was 1.1% (310 cases). In multivariate analysis, preoperative cerebrovascular disease had the strongest association with postoperative CVA (adjusted odds ratio = 2.29; p < .001). There was an inverse relationship between CVA incidence and ejection fraction (EF), with EF of 35%-39% conferring a 2.11 times higher risk compared to EF >55% (p < .001). CVA incidence was not different in on-pump versus off-pump cases; however, after 104 min or more on bypass patients had a 55% greater adjusted odds of CVA (p < .001). Other risk factors included poor kidney function, prior myocardial infarction, and intra-aortic balloon pump use.

CONCLUSION

The risk of CVA after CABG is multifactorial and involves multiple organ systems, including cardiac disease, poor renal function, and cerebrovascular disease, which was the strongest contributing risk factor. Optimization of these comorbidities and time on bypass may help improve clinical outcomes and lower the risk of this devastating complication.

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.

Ten-year outcomes after off-pump and on-pump coronary artery bypass grafting: an inverse probability of treatment weighting comparative study

AIMS

The debate on the advantages and limitations of off-pump myocardial revascularization (OPCAB) on long-term outcomes has not still arrived to a conclusion. This study was designed to compare the impact of OPCAB vs, on-pump coronary artery bypass grafting (CABG) on long-term mortality and major adverse cardiac and cerebrovascular events (MACCEs).

METHODS

The PRIORITY project was designed to evaluate the long-term outcomes of two large prospective multicenter cohort studies on CABG. Data on isolated CABG were linked to two administrative datasets. The inverse probability of treatment weight was employed to balance the treatment groups. Time-to-event methods were employed to analyze endpoints.

RESULTS

The cohort consisted of 10 988 patients who underwent isolated CABG (27.2% OPCAB). The median follow-up time was 7.9 years and was 100% complete. Unadjusted long-term survival was significantly worst for OPCAB, confirmed by weighted models (hazard ratio 1.08, 95% confidence interval (CI) 1.01-1.14, P = 0.01). OPCAB was associated to an increased risk of MACCE at 10 years (weighted hazard ratio 1.18, 95% CI 1.12-1.23, P < 0.001). Inside the MACCEs, OPCAB was significantly related to increased incidence of repeat revascularization (hazard ratio 2.27, 95% CI 1.39-3.85, P < 0.001, in the first 6 months, hazard ratio 1.19, 95% CI 1.09-1.32, P < 0.001 afterward) and stroke (hazard ratio 1.22, 95% CI 1.10-1.35, P < 0.001).

CONCLUSION

The results of this study suggest that OPCAB was associated with an increased risk of mortality, repeat myocardial revascularization and stroke at 10 years compared with on-pump CABG.

Guidelines on enhanced recovery after cardiac surgery under cardiopulmonary bypass or off-pump

OBJECTIVE

To provide recommendations for enhanced recovery after cardiac surgery (ERACS) based on a multimodal perioperative medicine approach in adult cardiac surgery patients with the aim of improving patient satisfaction, reducing postoperative mortality and morbidity, and reducing the length of hospital stay.

DESIGN

A consensus committee of 20 experts from the French Society of Anaesthesia and Intensive Care Medicine (Société française d'anesthésie et de réanimation, SFAR) and the French Society of Thoracic and Cardiovascular Surgery (Société française de chirurgie thoracique et cardio-vasculaire, SFCTCV) was convened. A formal conflict-of-interest policy was developed at the onset of the process and enforced throughout. The entire guideline process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide the assessment of the quality of evidence.

METHODS

Six fields were defined: (1) selection of the patient pathway and its information; (2) preoperative management and rehabilitation; (3) anaesthesia and analgesia for cardiac surgery; (4) surgical strategy for cardiac surgery and bypass management; (5) patient blood management; and (6) postoperative enhanced recovery. For each field, the objective of the recommendations was to answer questions formulated according to the PICO model (Population, Intervention, Comparison, Outcome). Based on these questions, an extensive bibliographic search was carried out and analyses were performed using the GRADE approach. The recommendations were formulated according to the GRADE methodology and then voted on by all the experts according to the GRADE grid method.

RESULTS

The SFAR/SFCTCV guideline panel provided 33 recommendations on the management of patients undergoing cardiac surgery under cardiopulmonary bypass or off-pump. After three rounds of voting and several amendments, a strong agreement was reached for the 33 recommendations. Of these recommendations, 10 have a high level of evidence (7 GRADE 1+ and 3 GRADE 1-); 19 have a moderate level of evidence (15 GRADE 2+ and 4 GRADE 2-); and 4 are expert opinions. Finally, no recommendations were provided for 3 questions.

CONCLUSIONS

Strong agreement existed among the experts to provide recommendations to optimise the complete perioperative management of patients undergoing cardiac surgery.

Effect of coronary artery bypass grafting on quality of life: a meta-analysis of randomized trials

AIMS

We conducted a systematic review and meta-analysis to evaluate temporal trends in quality of life (QoL) after coronary artery bypass grafting (CABG) surgery in randomized clinical trials, and a quantitative comparison from before surgery to up to 5 years after surgery.

METHODS AND RESULTS

We searched MEDLINE, CINAHL, EMBASE, Cochrane Library, and PsycINFO from 2010 to 2020 to identify studies that included the measurement of QoL in patients undergoing CABG. The primary outcome was the Seattle Angina Questionnaire (SAQ), and secondary outcomes were the 36-item Short Form Health Survey (SF-36) and EuroQol Questionnaire (EQ-5D). We pooled the means and the weighted mean differences over the follow-up period. In the meta-analysis, 2586 studies were screened and 18 full-text studies were included. There was a significant trend towards higher QoL scores from before surgery to 1 year post-operatively for the SAQ angina frequency (AF), SAQ QoL, SF-36 physical component (PC), and EQ-5D, whereas the SF-36 mental component (MC) did not improve significantly. The weighted mean differences from before surgery to 1 year after was 24 [95% confidence interval (CI): 21.6-26.4] for the SAQ AF, 31 (95% CI: 27.5-34.6) for the SAQ QoL, 9.8 (95% CI: 7.1-12.8) for the SF-36 PC, 7.1 (95% CI: 4.2-10.0) for the SF-36 MC, and 0.1 (95% CI: 0.06-0.14) for the EQ-5D. There was no evidence of publication bias or small-study effect.

CONCLUSION

CABG had both short- and long-term improvements in disease-specific QoL and generic QoL, with the largest improvement in angina frequency.

Graft Flow Evaluation with Intraoperative Transit-Time Flow Measurement in Off-Pump versus On-Pump coronary artery bypass grafting

Objective

We aimed to compare transit-time flow measurement (TTFM) parameters for on-pump (ONCAB) and off-pump (OPCAB) coronary artery bypass procedures.

Methods

The database of the Registry for Quality AssESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery (REQUEST) study was retrospectively reviewed. Only single grafts were included (ie, no sequential or Y/T grafts). Primary end points were mean graft flow (MGF), pulsatility index (PI), diastolic fraction (DF), and backflow (BF). Unadjusted and propensity score-matching comparisons were performed.

Results

Of 1016 patients in the REQUEST registry, 846 had at least 1 graft for which TTFM was performed. Of these, 512 patients (60.6%) underwent ONCAB and 334 (39.4%) OPCAB procedures. Mean arterial pressure (MAP) during measurements was higher in the OPCAB group. After propensity score-matching, 312 well balanced pairs were left. In these matched patients, MGF was higher for the ONCAB versus the OPCAB group (32 vs 28 mL/min, respectively, for all grafts [P < .001]; 30 vs 27 mL/min for arterial grafts [P = .002]; and 35 vs 31 mL/min for venous grafts [P = .006], respectively). PI was lower in the ONCAB group (2.1 vs 2.3, for all grafts; P < .001). Diastolic fraction was slightly lower in the ONCAB group (65% vs 67.5%; P < .001). The backflow was also lower in the ONCAB group (0.6 vs 1.3; P < .001) with trends similar to MGF and PI for venous and arterial grafts. There were 21 (3.3%) revisions in the OPCAB group and 14 (2.1%) in the ONCAB group (P = .198).

Conclusions

ONCAB surgery was associated with higher MGF and lower PI values, especially in venous grafts. Different TTFM cutoff values for ONCAB versus OPCAB surgery might be considered.

Ten-Year Outcomes of Off-Pump vs On-Pump Coronary Artery Bypass Grafting in the Department of Veterans Affairs: A Randomized Clinical Trial

IMPORTANCE

The long-term benefits of off-pump ("beating heart") vs on-pump coronary artery bypass grafting (CABG) remain controversial.

OBJECTIVE

To evaluate the 10-year outcomes and costs of off-pump vs on-pump CABG in the Department of Veterans Affairs (VA) Randomized On/Off Bypass (ROOBY) trial.

DESIGN, SETTING, AND PARTICIPANTS

From February 27, 2002, to May 7, 2007, 2203 veterans in the ROOBY trial were randomly assigned to off-pump or on-pump CABG procedures at 18 participating VA medical centers. Per protocol, the veterans were observed for 10 years; the 10-year, post-CABG clinical outcomes and costs were assessed via centralized abstraction of electronic medical records combined with merges to VA and non-VA databases. With the use of an intention-to-treat approach, analyses were performed from May 7, 2017, to December 9, 2021.

INTERVENTIONS

On-pump and off-pump CABG procedures.

MAIN OUTCOMES AND MEASURES

The 10-year coprimary end points included all-cause death and a composite end point identifying patients who had died or had undergone subsequent revascularization (ie, percutaneous coronary intervention [PCI] or repeated CABG); these 2 end points were measured dichotomously and as time-to-event variables (ie, time to death and time to composite end points). Secondary 10-year end points included PCIs, repeated CABG procedures, changes in cardiac symptoms, and 2018-adjusted VA estimated costs. Changes from baseline to 10 years in post-CABG, clinically relevant cardiac symptoms were evaluated for New York Heart Association functional class, Canadian Cardiovascular Society angina class, and atrial fibrillation. Outcome differences were adjudicated by an end points committee. Given that pre-CABG risks were balanced, the protocol-driven primary and secondary hypotheses directly compared 10-year treatment-related effects.

RESULTS

A total of 1104 patients (1097 men [99.4%]; mean [SD] age, 63.0 [8.5] years) were enrolled in the off-pump group, and 1099 patients (1092 men [99.5%]; mean [SD] age, 62.5 [8.5] years) were enrolled in the on-pump group. The 10-year death rates were 34.2% (n = 378) for the off-pump group and 31.1% (n = 342) for the on-pump group (relative risk, 1.05; 95% CI, 0.99-1.11; P = .12). The median time to composite end point for the off-pump group (4.6 years; IQR, 1.4-7.5 years) was approximately 4.3 months shorter than that for the on-pump group (5.0 years; IQR, 1.8-7.9 years; P = .03). No significant 10-year treatment-related differences were documented for any other primary or secondary end points. After the removal of conversions, sensitivity analyses reconfirmed these findings.

CONCLUSIONS AND RELEVANCE

No off-pump CABG advantages were found for 10-year death or revascularization end points; the time to composite end point was lower in the off-pump group than in the on-pump group. For veterans, in the absence of on-pump contraindications, a case cannot be made for supplanting the traditional on-pump CABG technique with an off-pump approach.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01924442.

Does the technique used in coronary artery bypass graft surgery affect patients' anxiety, depression, mental and physical health? First 3-month outcomes

PURPOSE

This study was aimed at investigating the effect of coronary artery bypass graft surgery conducted with different techniques on patients' anxiety, depression, mental and physical health.

DESIGN AND METHODS

This cross-sectional study included 60 patients who completed the Beck Anxiety Inventory, the Beck Depression Inventory, and the 36-Item Short-Form Health Survey.

FINDINGS

Anxiety, depression, and mental health showed significant differences in different time measurements, and combined effects of surgical technique and time factor.

PRACTICE IMPLICATIONS

Preoperative routine evaluations can speed up recovery, reduce cost, and improve quality of life by preventing the possible negative effects of anxiety and depression.

Factors affecting mortality after coronary bypass surgery: a scoping review

Objectives

Previous research reports numerous factors of post-operative mortality in patients undergoing isolated coronary artery bypass graft surgery. However, this evidence has not been mapped to the conceptual framework of care improvement. Without such mapping, interventions designed to improve care quality remain unfounded.

Methods

We identified reported factors of in-hospital mortality post isolated coronary artery bypass graft surgery in adults over the age of 19, published in English between January 1, 2000 and December 31, 2019, indexed in PubMed, CINAHL, and EMBASE. We grouped factors and their underlying mechanism for association with in-hospital mortality according to the augmented Donabedian framework for quality of care.

Results

We selected 52 factors reported in 83 articles and mapped them by case-mix, structure, process, and intermediary outcomes. The most reported factors were related to case-mix (characteristics of patients, their disease, and their preoperative health status) (37 articles, 27 factors). Factors related to care processes (27 articles, 12 factors) and structures (11 articles, 6 factors) were reported less frequently; most proposed mechanisms for their mortality effects.

Conclusions

Few papers reported on factors of in-hospital mortality related to structures and processes of care, where intervention for care quality improvement is possible. Therefore, there is limited evidence to support quality improvement efforts that will reduce variation in mortality after coronary artery bypass graft surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-022-01784-z.

Off-Pump Coronary Artery Bypass Grafting: Department of Veteran Affairs' Use and Outcomes

Background Coronary artery bypass can be performed off pump (OPCAB) without cardiopulmonary bypass. However, trends over time for OPCAB versus on-pump (ONCAB) use and long-term outcome has not been reported, nor has their long-term outcome been compared. Methods and Results We queried the national Veterans Affairs database (2005-2019) to identify isolated coronary artery bypass procedures. Procedures were classified as OPCAB on ONCAB using the as-treated basis. Trend analyses were performed to evaluate longitudinal changes in the preference for OPCAB. The median follow-up period was 6.6 (3.5-10) years. An inverse probability weighted Cox model was used to compare all-cause mortality between OPCAB and ONCAB. From 47 685 patients, 6759 (age 64±8 years) received OPCAB (14%). OPCAB usage declined from 16% (2005-2009) to 8% (2015-2019). Patients with triple vessel disease who received OPCAB received a lower mean number of grafts (2.8±0.8 versus 3.2±0.8; P<0.01). The ONCAB 5-, 10-, and 15-year survival rates were 82.9% (82.5-83.3), 60.4% (59.8-61.1), and 37.2% (36.1-38.4); correspondingly, OPCAB rates were 80.7% (79.7-81.7), 57.4% (56-58.7), and 34.1% (31.7-36.6) (P<0.01). OPCAB was associated with increased risk-adjusted all-cause mortality (hazard ratio, 1.15 [1.13-1.18]; P<0.01) and myocardial infarction (incident rate ratio, 1.16 [1.05-1.28]; P<0.01). Conclusions Over 15 years, OPCAB use declined considerably in Veterans Affairs medical centers. In Veterans Affairs hospitals, late all-cause mortality and myocardial infarction rates were higher in the OPCAB cohort.

Randomized evidence on graft patency after off-pump versus on-pump coronary artery bypass grafting: An updated meta-analysis

BACKGROUND

The debate between off-pump CABG (OPCAB) and on-pump CABG (ONCAB) has been ongoing for decades. We aimed to provide a comprehensive update of the current randomized controlled trials (RCTs) in evaluating the graft patency of OPCAB versus ONCAB.

MATERIALS AND METHODS

A literature search was conducted in PubMed, EMBASE, and the Cochrane Library databases until April 30, 2021. All RCTs from 2003 to 2020 comparing the results of graft patency between OPCAB and ONCAB were included. We compared the overall graft occlusion between the two groups, and subgroup analyses were conducted based on different types of conduits and target territories, crossover from off-pump to on-pump rate, and the length of follow-up.

RESULTS

Sixteen RCTs were identified, with 5743 grafts in the OPCAB group and 5898 in the ONCAB group. OPCAB was associated with a higher risk of occlusion in the overall graft (RR: 1.31; 95% CI, 1.17-1.46), saphenous vein graft (SVG) (RR: 1.40; 95% CI, 1.23-1.59), grafts to left anterior descending (LAD) territory (RR: 1.52; 95% CI, 1.11-2.08) and left circumflex artery (LCX) territory (RR: 1.45; 95% CI, 1.19-1.76), while no significant difference was observed between the two groups in respect of arterial conduits and grafts to right coronary artery (RCA) territory. Furthermore, the lower crossover rate and longer length of follow-up appeared to reduce the association between OPCAB and lower graft patency.

CONCLUSIONS

The current meta-analysis indicates that, compared with ONCAB, graft patency is poorer with OPCAB for overall grafts, SVG grafts, grafts to LAD and LCX territories, whereas the results remain comparable for arterial conduits and grafts to RCA territory.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

Off-Pump Coronary Artery Bypass Grafting; is it Still Relevant?

Off-pump Coronary Artery Bypass Grafting (OPCAB) experienced a resurgence in the 1980s -2000s and developed steadily with improvement of the instrumentation and techniques. However questions about graft patency and long-term survival of OPCAB patients still exist. This review attempts to explore the current relevance of OPCAB.

Long-Term Follow-Up of Device-Assisted Clampless Off-Pump Coronary Artery Bypass Grafting Compared with Conventional On-Pump Technique

STUDY OBJECTIVE

To evaluate the long-term outcomes of clampless off-pump coronary artery bypass grafting (C-OPCAB) compared with conventional on-pump double clamping coronary artery bypass grafting (C-CABG).

METHODS

From October 2006 to December 2011, 366 patients underwent isolated coronary artery bypass grafting. After propensity score matching of preoperative variables, 143 pairs were selected who received C-OPCAB with the use of device-assisted PAS-Port proximal venous graft anastomoses or C-CABG, performed by the same surgeon experienced in both techniques. Data of the two groups of patients were retrospectively analyzed up to 14 years of follow-up.

RESULTS

As compared with C-OPCAB, in the C-CABG patients, the performed number of grafts per patient was higher (2.9 ± 0.5 vs. 2.6 ± 0.6, p-value 0.0001). At 14 years, overall survival, including in-hospital death, was 64 ± 4.7% for the C-OPCAB vs. 55 ± 5.5% for the C-CABG, freedom from overall MACCEs 51 ± 6.2% vs. 41 ± 7.7%, and from late cardiac death 94 ± 2.4% vs. 96 ± 2.2% (p-value not significant, for all comparisons). No significant statistical differences were observed in the actual rates of adverse events during follow-up. Independent predictors of survival were advanced age at operation (p-value 0.001) and a lower mean value of preoperative left ventricular ejection fraction (p-value 0.015).

CONCLUSIONS

Our single-center study analysis suggests that clampless OPCAB using device-assisted proximal anastomoses proved to be not inferior to double-clamping CABG in the long-term follow-up, provided that involved surgeons are familiar with both techniques. These conclusions are supported by a large and long-term follow-up period, eliminating potential bias, i.e., by means of the propensity score matching and analyzing single-surgeon experience.

Methodological Standards for the Design, Implementation, and Analysis of Randomized Trials in Cardiac Surgery: A Scientific Statement From the American Heart Association

Cardiac surgery presents specific methodological challenges in the design, implementation, and analysis of randomized controlled trials. The purposes of this scientific statement are to review key standards in cardiac surgery randomized trial design and implementation, and to provide recommendations for conducting and interpreting cardiac surgery trials. Recommendations include a careful evaluation of the suitability of the research question for a clinical trial, assessment of clinical equipoise, feasibility of enrolling a representative patient cohort, impact of practice variations on the safety and efficacy of the study intervention, likelihood and impact of crossover, and duration of follow-up. Trial interventions and study end points should be predefined, and appropriate strategies must be used to ensure adequate deliverability of the trial interventions. Every effort must be made to ensure a high completeness of follow-up; trial design and analytic techniques must be tailored to the specific research question and trial setting.

Assessment of Nonfatal Myocardial Infarction as a Surrogate for All-Cause and Cardiovascular Mortality in Treatment or Prevention of Coronary Artery Disease: A Meta-analysis of Randomized Clinical Trials

IMPORTANCE

Although nonfatal myocardial infarction (MI) is associated with an increased risk of mortality, evidence validating nonfatal MI as a surrogate end point for all-cause or cardiovascular (CV) mortality is lacking.

OBJECTIVE

To examine whether nonfatal MI may be a surrogate for all-cause or CV mortality in patients with or at risk for coronary artery disease.

DATA SOURCES

In this meta-analysis, PubMed was searched from inception until December 31, 2020, for randomized clinical trials of interventions to treat or prevent coronary artery disease reporting mortality and nonfatal MI published in 3 leading journals.

STUDY SELECTION

Randomized clinical trials including at least 1000 patients with 24 months of follow-up.

DATA EXTRACTION AND SYNTHESIS

Trial-level correlations between nonfatal MI and all-cause or CV mortality were assessed for surrogacy using the coefficient of determination (R2). The criterion for surrogacy was set at 0.8. Subgroup analyses based on study subject (primary prevention, secondary prevention, mixed primary and secondary prevention, and revascularization), era of trial (before 2000, 2000-2009, and 2010 and after), and follow-up duration (2.0-3.9, 4.0-5.9, and ≥6.0 years) were performed.

MAIN OUTCOMES AND MEASURES

All-cause or CV mortality and nonfatal MI.

RESULTS

A total of 144 articles randomizing 1 211 897 patients met the criteria for inclusion. Nonfatal MI did not meet the threshold for surrogacy for all-cause (R2 = 0.02; 95% CI, 0.00-0.08) or CV (R2 = 0.11; 95% CI, 0.02-0.27) mortality. Nonfatal MI was not a surrogate for all-cause mortality in primary (R2 = 0.01; 95% CI, 0.001-0.26), secondary (R2 = 0.03; 95% CI, 0.00-0.20), mixed primary and secondary prevention (R2 = 0.001; 95% CI, 0.00-0.08), or revascularization trials (R2 = 0.21; 95% CI, 0.002-0.50). For trials enrolling patients before 2000 (R2 = 0.22; 95% CI, 0.08-0.36), between 2000 and 2009 (R2 = 0.02; 95% CI, 0.00-0.17), and from 2010 and after (R2 = 0.01; 95% CI, 0.00-0.09), nonfatal MI was not a surrogate for all-cause mortality. Nonfatal MI was not a surrogate for all-cause mortality in randomized clinical trials with 2.0 to 3.9 (R2 = 0.004; 95% CI, 0.00-0.08), 4.0 to 5.9 (R2 = 0.06; 95% CI, 0.001-0.16), or 6.0 or more years of follow-up (R2 = 0.30; 95% CI, 0.01-0.55).

CONCLUSIONS AND RELEVANCE

The findings of this meta-analysis do not appear to establish nonfatal MI as a surrogate for all-cause or CV mortality in randomized clinical trials of interventions to treat or prevent coronary artery disease.

Comparison of long-term outcomes between off-pump and on-pump coronary artery bypass grafting using Japanese nationwide cardiovascular surgery database

OBJECTIVES

In Japan, off-pump coronary artery bypass (OPCAB) is more common than on-pump coronary artery bypass. Superior early results of OPCAB have been reported; however, long-term results were still unclear. Purpose of this study is to evaluate the clinical outcomes of OPCAB in Japan using Japan Adult Cardiovascular Surgery Database.

METHODS

Between 2008 and 2010, 23,633 patients who underwent isolated coronary artery bypass were reported in database. We selected the cases from the hospital with mean annual coronary surgery volume of more than 50. Among the total of 7724 cases at 41 institutions, 2150 (31.2%) on-pump coronary artery bypass (ONCAB) and 5574 (68.8%) OPCAB cases were included. Propensity score (PS) matching was performed using PS developed from patient characteristics and preoperative factors resulting in 2007 cases matched pairs. Long-term follow-up data on patients' mortality and stroke were collected.

RESULTS

In-hospital mortality was significantly lower in OPCAB (ONCAB 1.1%, OPCAB 0.4% p = 0.01). Stroke was low in OPCAB group (ONCAB 1.7%, OPCAB 0.8%, p = 0.01). There was no statistically significant difference between OPCAB and ONCAB regarding 7-year overall survival (86.1% vs 88.1% respectively), composite outcomes (72.0% vs 73.9% respectively), or cardiac deaths (97.3% vs 97.1% respectively). Subgroup analysis (more than 75 years old) showed a worse trend in OPCAB group. Only in OPCAB group, incomplete revascularization significantly influenced 7-year survival.

CONCLUSIONS

OPCAB is associated with early prognostic benefits; however, it might be less favorable outcomes in the long term when patients are older or with incomplete revascularization.

A systematic review and meta-analysis of randomized controlled studies comparing off-pump versus on-pump coronary artery bypass grafting in the elderly

AIM

Comparison of short and mid-term outcomes between off-pump CABG (OPCAB) and on-pump CABG (ONCAB) in patients older than 65 throughout a meta-analysis of randomized clinical trials (RCTs).

EVIDENCE ACQUISITION

A literature search was conducted using 3 databases. RCTs reporting mortality outcomes of OPCAB versus ONCAB among the elderly were included. Data on myocardial infarction, stroke, re-revascularization, renal failure and composite endpoints after CABG were also collected. Random effects models were used to compute statistical combined measures and 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

Five RCTs encompassing 6221 patients were included (3105 OPCAB and 3116 ONCAB). There were no significant differences on mid-term mortality (pooled HR: 1.02, 95%CI: 0.89-1.17, p=0.80) and composite endpoint incidence (pooled HR: 0.98, 95%CI: 0.88-1.09, p=0.72) between OPCAB and ONCAB. At 30-day, there were no differences in mortality, myocardial infarction, stroke and renal complications. The need for early re-revascularization was significantly higher in OPCAB (pooled OR: 3.22, 95%CI: 1.28-8.09, p=0.01), with a higher percentage of incomplete revascularization being reported for OPCAB in trials included in this pooled result (34% in OPCAB vs 29% in ONCAB, p<0.01).

CONCLUSIONS

Data from RCTs in elderly patients showed that OPCAB and ONCAB provide similar mid-term results. OPCAB was associated with a higher risk of early rerevascularization. As CABG on the elderly is still insufficiently explored, further RCTs, specifically designed targeting this population, are needed to establish a better CABG strategy for these patients.

The value of perioperative biomarker release for the assessment of myocardial injury or infarction in cardiac surgery

OBJECTIVES

Cardiac biomarkers are indicators of irreversible cell damage. Current myocardial infarction (MI) definitions require concomitant clinical characteristics. For perioperative MI, a correlation of biomarker elevations and mortality has been suggested. Definitions emerged relying on cardiac biomarker release only. This approach is questionable as several clinical and experimental scenarios exist where relevant biomarker release can occur apart from MI.

METHODS

We reviewed the clinical and basic science literature and revealed important aspects regarding the use and interpretation of cardiac biomarker release with special focus on their interpretation in the perioperative setting.

RESULTS

Ischaemic biomarkers may be released without cell death in multiple conditions, such as after endurance runs in athletes, temporary inotropic stimulation in animal models and flow variations in in vitro cell models. In addition, access through atrial tissue during cannulation or concomitant valve procedures adds sources of enzyme release that may not be related to ventricular ischaemia (i.e. MI). Such non-cell death-related mechanisms may explain the lack of poor correlations of enzyme release and long-term outcomes in recent trials. In addition, the 3 main biomarkers, troponin T, I and creatine kinase myocardial band, differ in their release kinetics, which may differentially trigger MI events in trial patients.

CONCLUSIONS

The identification of irreversible myocardial injury in cardiac surgery based only on biomarker release is unreliable. Cell death- and non-cell death-related mechanisms create a mix in the perioperative setting that requires additional markers for proper identification of MI. In addition, the 3 most common ischaemic biomarkers display different release kinetics adding to the confusion. We review the topic.

SUBJ COLLECTION

120, 123.

Cardiac Surgery Associated AKI Prevention Strategies and Medical Treatment for CSA-AKI

Acute kidney injury (AKI) is common after cardiac surgery. To date, there are no specific pharmacological therapies. In this review, we summarise the existing evidence for prevention and management of cardiac surgery-associated AKI and outline areas for future research. Preoperatively, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers should be withheld and nephrotoxins should be avoided to reduce the risk. Intraoperative strategies include goal-directed therapy with individualised blood pressure management and administration of balanced fluids, the use of circuits with biocompatible coatings, application of minimally invasive extracorporeal circulation, and lung protective ventilation. Postoperative management should be in accordance with current KDIGO AKI recommendations.

Expertise-based design in surgical trials: a narrative review

Randomized controlled trials (RCTs) are the most robust study design for evaluating the safety and efficacy of a therapeutic intervention. However, their internal validity are at risk when evaluating surgical interventions. This review summarizes existing expertise- based trials in surgery and related methodological concepts to guide surgeons performing this work. We provide caseloads required to reach the learning curve for various surgical interventions and report criteria for expertise from published and unpublished expertise-based trials. In addition, we review design and implementation concepts of expertise-based trials, including recruitment of surgeons, crossover, ethics, generalizability, sample size and definitions for learning curve. Several RCTs have used an expertise-based design. We found that the majority of definitions used for expertise were vague, heterogeneous, and inconsistent across trials evaluating the same surgical intervention. Statistical methods exist to adjust for the learning curve; however, there is limited guidance. We developed the following criteria for surgical expertise for future trials: 1) decide on the proxy to be used for the learning curve, and 2) assess eligible surgeons by comparing their performance to the previously defined expertise criteria.

Impact of early quantitative morbidity on 1-year outcomes in coronary artery bypass graft surgery

OBJECTIVES

We applied the Clavien-Dindo Complications Classification (CDCC) and the Comprehensive Complication Index (CCI) to the CORONARY trial to assess whether quantitative early morbidity affects outcomes at 1 year.

METHODS

All postoperative hospitalization and 30-day follow-up complications were assigned a CDCC grade. CCI were calculated for all patients (n = 4752). Kaplan-Meier analysis examined 1-year mortality and 1-year co-primary outcome (i.e. death, non-fatal stroke, non-fatal myocardial infarction, new-onset renal failure requiring dialysis or repeat coronary revascularization) by CDCC grade. Multivariable logistic regression evaluated the predictive value of CCI for both outcomes.

RESULTS

For off-pump and on-pump coronary artery bypass graft surgery, median CDCC were 1 [interquartile range: 0, 2] and 2 [1, 2] (P < 0.001), while median CCI were 8.7 [0, 22.6] and 20.9 [8.7, 29.6], respectively (P < 0.001). In on-pump, there were more grade I and grade II complications, particularly grade I and II transfusions (P < 0.001) and grade I acute kidney injury (P = 0.039), and more grade IVa respiratory failures (P = 0.047). Patients with ≥IIIa complications had greater cumulative 1-year mortality (P < 0.001). The median CCI was 8.7 [0, 22.6] in patients who survived and 22.6 [8.7, 44.3] in patients who died at 1 year (P < 0.001). The CCI remained an independent risk factor for 1-year mortality and 1-year co-primary outcome after multivariable adjustment (P < 0.001).

CONCLUSIONS

On-pump coronary artery bypass graft surgery had a greater number of complications in the early postoperative period, likely driven by transfusions, respiratory outcomes and acute kidney injury. This affects 1-year outcomes. Similar analyses have not yet been used to compare both techniques and could prove useful to quantify procedural morbidity.

CLINICAL TRIAL REGISTRATION

https://www.clinicaltrials.gov/ct2/show/NCT00463294; Unique Identifier: NCT00463294.

The Influence of Choice of Surgical Procedure on Long-Term Survival After Cardiac Surgery

BACKGROUND

There is some interest in long-term survival after various cardiac surgical strategies, including off-pump versus on-pump coronary artery surgery (CAG), mitral valve (MV) repair versus replacement, and aortic valve (AV) bioprosthetic versus mechanical replacement.

METHODS

We studied patients older than 49 years of age, recording risk factors and surgical details at the time of surgery. We classified procedures as: MV surgery with or without concurrent grafts or valves; AV surgery with or without concurrent CAG; or isolated CAG. Follow-up was through the state death register and state-wide hospital attendance records. Risk-adjusted survival was estimated using Cox proportional hazards. Observed survival was compared to the expected age- and sex- matched population survival.

RESULTS

During a median follow-up of 14.8 years 5,807 of 11,718 patients died. The difference between observed and expected survival varied between 3.4 years for AV surgery and 9.6 years for females undergoing MV surgery. The risk-adjusted mortality hazard rate after off-pump CAG was 0.93 (95% CI 0.8-1.0, p=0.84), MV repair 0.67 (95% CI 0.6-0.8, p<0.0001), MV bioprosthesis 0.82 (95% CI 0.81 (0.6-1.0, p=0.11) and bioprosthetic AV replacement 1.02 (95% CI 0.9-1.2, p=0.82).

CONCLUSIONS

Compared to the general population, cardiac surgical patients have a shorter than expected life expectancy. We observed a survival benefit of mitral valve repair over replacement. We did not observe significant survival differences between off-pump and on-pump CAG, nor between bioprosthetic and mechanical replacement.

Post-surgical wireless monitoring of arterial health progression

Early detection of limb ischemia, strokes, and heart attacks may be enabled via long-term monitoring of arterial health. Early stenosis, decreased blood flow, and clots are common after surgical vascular bypass or plaque removal from a diseased vessel and can lead to the above diseases. Continuous arterial monitoring for the early diagnosis of such complications is possible by implanting a sensor during surgery that is wirelessly monitored by patients after surgery. Here, we report the design of a wireless capacitive sensor wrapped around the artery during surgery for continuous post-operative monitoring of arterial health. The sensor responds to diverse artery sizes and extents of occlusion in vitro to at least 20 cm upstream and downstream of the sensor. It demonstrated strong capability to monitor progression of arterial occlusion in human cadaver and small animal models. This technology is promising for wireless monitoring of arterial health for pre-symptomatic disease detection and prevention.

Saphenous Vein Graft Failure: From Pathophysiology to Prevention and Treatment Strategies

Saphenous vein grafts (SVGs) remain the most frequently used conduits in coronary artery bypass graft surgery (CABG). Despite advances in surgical techniques and pharmacotherapy, SVG failure rates remain high, often leading to repeat coronary revascularization. The no-touch SVG harvesting technique (minimal graft manipulation with preservation of vasa vasorum and nerves) reduces the risk of SVG failure, whereas the effect of the off-pump technique on SVG patency remains unclear. Use of buffered storage solutions, intraoperative graft flow measurement, careful selection of the target vessels, and physiological assessment of the native coronary circulation before CABG may also reduce the incidence of SVG failure. Perioperative aspirin and high-intensity statin administration are the cornerstones of secondary prevention after CABG. Dual antiplatelet therapy is recommended for off-pump CABG and in patients with a recent acute coronary syndrome. Intermediate (30%-60%) SVG stenoses often progress rapidly. Stenting of intermediate SVG stenoses failed to improve outcomes; hence, treatment focuses on strict control of coronary artery disease risk factors. Redo CABG is associated with higher perioperative mortality compared with percutaneous coronary intervention (PCI); hence, the latter is preferred for most patients requiring repeat revascularization after CABG. SVG PCI is limited by high rates of no-reflow and a high incidence of restenosis during follow-up. Drug-eluting and bare metal stents provide similar long-term outcomes in SVG PCI. Embolic protection devices reduce no-reflow and should be used when feasible. PCI of the corresponding native coronary artery is associated with better short- and long-term outcomes and is preferred over SVG PCI, if technically feasible.

Mid-term outcomes of off-pump versus on-pump coronary artery bypass graft surgery; statistical challenges in comparison

BACKGROUND

Despite several studies comparing off- and on-pump coronary artery bypass grafting (CABG), the effectiveness and outcomes of off-pump CABG still remain uncertain.

METHODS

In this registry-based study, we assessed 8163 patients who underwent isolated CABG between 2014 and 2016. Propensity score matching (PSM), inverse probability of weighting (IPW) and covariate adjustment were performed to correct for and minimize selection bias.

RESULTS

The overall mean age of the patients was 62 years, and 25.7% were women. Patients who underwent off-pump CABG had shorter length of hospitalization (p < 0.001), intubation time (p = 0.003) and length of ICU admission (p < 0.001). Off-pump CABG was associated with higher risk of 30-days mortality (OR: 1.7; 95% CI 1.09-2.65; p = 0.019) in unadjusted analysis. After covariate adjustment and matching (PSM and IPW), this difference was not statistically significant. After an average of 36.1 months follow-up, risk of MACCE and all-cause mortality didn't have significant differences in both surgical methods by adjusting with IPW (HR: 1.03; 95% CI 0.87-1.24; p = 0.714; HR: 0.91; 95% CI 0.73-1.14; p = 578, respectively).

CONCLUSION

Off-pump and on-pump techniques have similar 30-day mortality (adjusted, PSM and IPW). Off-pump surgery is probably more cost-effective in short term; however, mid-term survival and MACCE trends in both surgical methods are comparable.

Long-Term Survival After On-Pump and Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Off-pump coronary artery bypass grafting (CABG) may be associated with increased hazard for long-term mortality as compared to on-pump CABG. We sought to evaluate risk-adjusted long-term survival after off-pump and on-pump CABG, particularly among high-volume and low-volume CABG surgeons.

METHODS

We evaluated 1,235,089 isolated CABGs (off-pump = 209,085; on-pump = 1,026,004) performed in Medicare beneficiaries from 2001-2015. Long-term hazard for mortality after off-pump versus on-pump CABG was compared with Kaplan-Meier and log-rank analysis among all CABG surgeons as well as high-volume and low-volume CABG surgeons, before and after inverse-probability of treatment weighting (IPTW) to adjust for confounding.

RESULTS

Among all surgeons, off-pump CABG was associated with a statistically-significant hazard for mortality as compared to on-pump CABG before and after IPTW (median survival: off-pump 9.8 years vs on-pump 10.2 years; difference in median survival -134 days; log-rank p<0.001). Cox regression analysis confirmed an interaction between surgeon volume and long-term mortality. The hazard for mortality associated with off-pump CABG was decreased among high-volume surgeons (difference in median survival: -84 days; log-rank p<0.001) and increased among low-volume surgeons (difference in median survival: -240 days; long-rank p<0.001).

CONCLUSIONS

Off-pump CABG was associated with a significant, but clinically modest, increased hazard for mortality as compared to on-pump CABG. The hazard was reduced when off-pump CABG was performed by high-volume CABG surgeons.

Off-pump coronary artery bypass grafting is safe and effective in patients with severe left ventricular dysfunction

OBJECTIVES

Severe left ventricular dysfunction (LVD) is associated with increased risk following coronary artery bypass grafting (CABG). Due to a dearth of reports on the choice of CABG technique in patients with LVD, this study aims to compare the outcomes of off-pump CABG (OPCAB) and conventional CABG (ONCAB) in such patients.

METHODS

Retrospective single-centre propensity-matched analysis comparing early- and long-term outcomes of OPCAB and ONCAB in patients with severe LVD. Primary outcome was long-term all-cause mortality.

RESULTS

Between 2002 and 2014, a total of 1161 consecutive patients with severe LVD underwent isolated CABG [442 patients underwent OPCAB and 719 ONCAB (430 matched pairs)]. Incomplete revascularization was observed more frequently among OPCAB than ONCAB patients (35.3% vs 21.6%; P < 0.01). The overall 30-day mortality was 5% and was comparable between the matched groups [OR 0.64 (0.34-1.22); P = 0.18]. OPCAB patients had shorter median hospital stay (11 vs 12 days; P = 0.02) and lower packed red blood cell transfusion rates [2.7 (2.21-3.19) vs 4.4 (3.56-5.24); P < 0.01]. Estimated adjusted survival was 86.0% vs 85.8%, 69.1% vs 65.5% and 59.9% vs 49.1% at 1, 5 and 10 years for OPCAB and ONCAB patients, respectively (P = 0.99). Long-term risk of mortality was similar between groups [hazard ratio (HR) 0.94 (0.66-1.32); P = 0.7]. Incomplete revascularization was weakly associated with increased risk of long-term all-cause mortality [HR 1.33 (0.99-1.77); P = 0.05].

CONCLUSIONS

OPCAB is safe and effective in patients with severe LVD. Although incomplete revascularization is more commonly observed in patients undergoing OPCAB, it is not associated with increased late mortality.

Real-World Outcomes of On- vs Off-Pump Coronary Bypass Surgery: Result from Korean Nationwide Cohort

BACKGROUND

While several randomized trials have shown conflicting results regarding the comparative effectiveness of on- and off-pump coronary arterial bypass grafting (CABG), research on long-term outcomes in large-scale, real-world clinical settings are limited. We sought to examine the comparative effectiveness of on- and off-pump CABG in a real-world clinical setting.

METHODS

Using the nationwide claims database of the Korean National Health Insurance Service, we identified patients who underwent isolated CABG from 2004 to 2013. Propensity-score matching with multivariable adjustment was used to assemble a cohort of patients with similar baseline characteristics.

RESULTS

Among 23,828 patients, 12,639 in the off-pump (53.0%) and 11,189 in the on-pump (47.0%) groups were enrolled. After matching, 6,483 pairs were included in the final analysis. At 30 days, there was no significant difference in adjusted mortality between the off- and on-pump groups (hazard ratio [HR], 1.00; 95% confidence interval [CI], 0.87-1.16). During long-term follow-up (100% complete; median 5.3yrs, maximum 13.2yrs), however, off-pump CABG was associated with a higher risk of mortality than on-pump CABG (HR, 1.09; 95% CI, 1.03-1.15). The risks of myocardial infarction (MI) (HR, 1.3; 95% CI, 1.16-1.45) and repeat revascularization (HR, 1.50; 95% CI, 1.37-1.63) were also significantly higher in the off-pump CABG group than in the on-pump CABG group, while the stroke risk was similar inter-groups (HR, 0.99; 95% CI, 0.87-1.13).

CONCLUSIONS

In this contemporary, nationwide, clinical practice claim registry, off-pump CABG was associated with higher long-term risks of mortality, MI, and repeat revascularization than on-pump CABG.

Representation of Women in Randomized Trials in Cardiac Surgery: A Meta-Analysis

Background

Women have traditionally been underrepresented in randomized clinical trials (RCTs). We performed a systematic evaluation of the inclusion of women in cardiac surgery RCTs published in the past 2 decades.

Methods and Results

MEDLINE, EMBASE, and the Cochrane Library were searched (2000 to July 2020) for RCTs written in English, comparing ≥2 adult cardiac surgical procedures. The percentage of women enrolled and its association with year of publication, sample size, mean age, funding source, geographic location, number of sites involved, and interventions tested were analyzed using a meta‐analytic approach. Fifty‐one trials were included. Of 25 425 total patients, 5029 were women (20.8%; 95% CI, 17.6–24.4; range, 0.5%–57.9%). The proportion of women dropped significantly during the study period (29.6% in 2000 versus 13.1% in 2019, P<0.001). Women were significantly more represented in European trials (26.2%; 95% CI, 21.2–31.9), and less represented in trials of coronary bypass surgery versus other interventions (16.8%; 95% CI, 12.3–22.7 versus 33.6%; 95% CI, 27.4–40.5; P=0.0002) and in trials enrolling younger patients (P=0.009); the percentage of women was higher in industry‐sponsored versus non‐industry sponsored trials (31.7%; 95% CI, 27.2–36.6 versus 15.5%; 95% CI, 10.0–23.2; P=0.0004) and was not associated with trial sample size (P=0.52) or study design (multicenter versus monocenter: P=0.22). After exclusion of trials conducted at Veteran Affairs centers, women representation was 24.4% (95% CI, 21.1–28.0; range, 10.4%–57.9%), with no significant changes during the study period.

Conclusions

The proportion of women in cardiac surgery trials is low and likely inadequate to provide meaningful estimates of the treatment effect.

Sex differences in outcomes after coronary artery bypass grafting: a pooled analysis of individual patient data

AIMS

Data suggest that women have worse outcomes than men after coronary artery bypass grafting (CABG), but results have been inconsistent across studies. Due to the large differences in baseline characteristics between sexes, suboptimal risk adjustment due to low-quality data may be the reason for the observed differences. To overcome this limitation, we undertook a systematic review and pooled analysis of high-quality individual patient data from large CABG trials to compare the adjusted outcomes of women and men.

METHODS AND RESULTS

The primary outcome was a composite of all-cause mortality, myocardial infarction (MI), stroke, and repeat revascularization (major adverse cardiac and cerebrovascular events, MACCE). The secondary outcome was all-cause mortality. Multivariable mixed-effect Cox regression was used. Four trials involving 13 193 patients (10 479 males; 2714 females) were included. Over 5 years of follow-up, women had a significantly higher risk of MACCE [adjusted hazard ratio (HR) 1.12, 95% confidence interval (CI) 1.04-1.21; P = 0.004] but similar mortality (adjusted HR 1.03, 95% CI 0.94-1.14; P = 0.51) compared to men. Women had higher incidence of MI (adjusted HR 1.30, 95% CI 1.11-1.52) and repeat revascularization (adjusted HR 1.22, 95% CI 1.04-1.43) but not stroke (adjusted HR 1.17, 95% CI 0.90-1.52). The difference in MACCE between sexes was not significant in patients 75 years and older. The use of off-pump surgery and multiple arterial grafting did not modify the difference between sexes.

CONCLUSIONS

Women have worse outcomes than men in the first 5 years after CABG. This difference is not significant in patients aged over 75 years and is not affected by the surgical technique.

Risk-adjusted analysis of long-term outcomes after on- versus off-pump coronary artery bypass grafting

OBJECTIVES

Recent data suggested that off-pump coronary artery bypass (OPCAB) may carry a higher risk for mortality in the long term when compared to on-pump coronary artery bypass (ONCAB). We, therefore, compared long-term survival and morbidity in patients undergoing ONCAB versus OPCAB in a large single-centre cohort.

METHODS

A total of 8981 patients undergoing isolated elective/urgent coronary artery bypass grafting between January 2009 and December 2019 were analysed. Patients were stratified into 2 groups (OPCAB n = 6649/ONCAB n = 2332). The primary end point was all-cause mortality. Secondary endpoints included repeat revascularization, stroke and myocardial infarction. To adjust for potential selection bias, 1:1 nearest neighbour propensity score (PS) matching was performed resulting in 1857 matched pairs. Moreover, sensitivity analysis was applied in the entire study cohort using multivariable- and PS-adjusted Cox regression analysis.

RESULTS

In the PS-matched cohort, 10-year mortality was similar between study groups [OPCAB 36.4% vs ONCAB 35.8%: hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.87-1.12; P = 0.84]. While 10-year outcomes of secondary endpoints did not differ significantly, risk of stroke (OPCAB 1.50% vs ONCAB 2.8%: HR 0.51, 95% CI 0.32-0.83; P = 0.006) and mortality (OPCAB 3.1% vs ONCAB 4.8%: HR 0.65, 95% CI 0.47-0.91; P = 0.011) at 1 year was lower in the OPCAB group. In the multivariable- and the PS-adjusted model, mortality at 10 years was not significantly different (OPCAB 34.1% vs ONCAB 35.7%: HR 0.97, 95% CI 0.87-1.08; P = 0.59 and HR 1.01, 95% CI 0.90-1.13; P = 0.91, respectively).

CONCLUSIONS

Data do not provide evidence that elective/urgent OPCAB is associated with significantly higher risks of mortality, repeat revascularization, or myocardial infarction during late follow-up when compared to ONCAB. Patients undergoing OPCAB may benefit from reduced risks of stroke and mortality within the first year postoperatively.

Five-year patency for the no-touch saphenous vein and the left internal thoracic artery in on- and off-pump coronary artery bypass grafting

BACKGROUND

Randomized trials show high long-term patency for no-touch saphenous vein grafts in coronary artery bypass grafting. The patency rate in off-pump coronary bypass surgery for these grafts has not been investigated. Our center participated in the CORONARY randomized trial, NCT00463294. This is a study aimed to assess the patency of no-touch saphenous veins in on- versus off-pump coronary bypass surgery at five-year follow-up.

METHODS

Fifty-six patients were included. Forty of 49 patients, alive at 5 years, participated in this follow-up. There were 21 and 19 patients in the on- and off-pump groups respectively. No-touch saphenous veins were used to bypass all targets and in some cases the left anterior descending artery. Graft patency according to distal anastomosis was evaluated with computed tomography angiography.

RESULTS

The five-year patency rate was 123/139 (88.5%). The patency for the no-touch vein grafts was 57/64 (89.1%) in the on-pump versus 37/45 (82.2%) in the off-pump group. All left internal thoracic arteries except for one, 29/30 (96.6%), were patent. All vein grafts used to bypass the left anterior descending and the diagonal arteries were patent 32/32. The lowest patency rate for the saphenous veins was to the right coronary territory, particularly in off-pump surgery (80.0% vs. 62.5% for the on- respective off-pump groups).

CONCLUSIONS

Comparable 5-year patency for the no-touch saphenous veins and the left internal thoracic arteries to the left anterior descending territory in both on- and off-pump coronary artery bypass grafting. Graft patency in off-pump CABG is lower to the right coronary artery.