Meta-Analysis of Repeat Revascularization of Off-Pump and On-Pump Coronary Artery Bypass Surgery

Clinical outcomes of on-pump versus off-pump coronary-artery bypass surgery: a meta-analysis

BACKGROUND

The ongoing debate regarding off-pump coronary artery bypass grafting (CABG) and on-pump CABG has endured for over three decades. Although numerous randomized controlled trials (RCTs) and meta-analyses have been reported, new evidence has emerged. Therefore, an updated and comprehensive meta-analysis to guide clinical practice is essential.

MATERIALS AND METHODS

A comprehensive search for eligible articles published after 2000, reporting RCTs involving at least 100 patients and comparing off-pump CABG with on-pump CABG, was performed throughout the databases including Embase, Ovid Medline, and Web of Science. The primary interested outcomes included the short-term incidence of stroke and long-term mortality. The primary analysis utilized fixed-effect model with the inverse variance method. The Grade of Recommendations Assessment, Development, and Evaluation (GRADE) was used to evaluate the certainty of evidence.

RESULTS

After thorough screening, 39 articles were included, consisting of 28 RCTs and involving a total of 16 090 patients. Off-pump CABG significantly reduced the incidence of short-term stroke (1.27 vs. 1.78%, OR: 0.74, P =0.03, high certainty). However, it was observed to be associated with increased mid-term coronary reintervention (2.77 vs. 1.85%, RR: 1.49, P <0.01, high certainty) and long-term mortality (21.8 vs. 21.0%, RR: 1.09, P =0.02, moderate certainty).

CONCLUSIONS

Off-pump CABG significantly reduces the short-term incidence of stroke, but it also increases the incidence of mid-term coronary reintervention. Moreover, it may increase long-term mortality.

Controversy. On pump or off pump: what will I do when I grow up? A narrative systematic review

The transition from the second to the third millennium happened to be a turning point in the history of myocardial revascularization on a beating heart, which moved from technical development to critical evaluation. This article describes how the initial acceptance and spread of off-pump coronary artery bypass grafting (OPCABG) was followed by the general perception that the technique could not fulfill the expectations placed in it and provides some insight on what should we do with the know-how of OPCABG in the present and the future of coronary surgical revascularization.

The ebb and flow of cardiac lymphatics: a tidal wave of new discoveries

The heart is imbued with a vast lymphatic network that is responsible for fluid homeostasis and immune cell trafficking. Disturbances in the forces that regulate microvascular fluid movement can result in myocardial edema, which has profibrotic and proinflammatory consequences and contributes to cardiovascular dysfunction. This review explores the complex relationship between cardiac lymphatics, myocardial edema, and cardiac disease. It covers the revised paradigm of microvascular forces and fluid movement around the capillary as well as the arsenal of preclinical tools and animal models used to model myocardial edema and cardiac disease. Clinical studies of myocardial edema and their prognostic significance are examined in parallel to the recent elegant animal studies discerning the pathophysiological role and therapeutic potential of cardiac lymphatics in different cardiovascular disease models. This review highlights the outstanding questions of interest to both basic scientists and clinicians regarding the roles of cardiac lymphatics in health and disease.

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.

Contemporary coronary artery bypass graft surgery and subsequent percutaneous revascularization

Patients who have undergone coronary artery bypass graft (CABG) surgery are susceptible to bypass graft failure and progression of native coronary artery disease. Although the saphenous vein graft (SVG) was traditionally the most-used conduit, arterial grafts (including the left and right internal thoracic arteries and the radial artery) have improved patency rates. However, the need for secondary revascularization remains common, and percutaneous coronary intervention (PCI) has become the most common modality of secondary revascularization after CABG surgery. Procedural characteristics and clinical outcomes differ considerably from those associated with PCI in patients without previous CABG surgery, owing to altered coronary anatomy and differences in conduit pathophysiology. In particular, SVG PCI carries an increased risk of complications, and operators are shifting their focus towards embolic protection strategies and complex native-vessel interventions, increasingly using SVGs as conduits to facilitate native-vessel PCI rather than pursuing SVG PCI. In this Review, we discuss the differences in conduit pathophysiology, changes in CABG surgery techniques, and the latest evidence in terms of PCI in patients with previous CABG surgery, with a particular emphasis on safety and long-term efficacy. We explore the subject of contemporary CABG surgery and subsequent percutaneous revascularization in this complex patient population.

Association Between Triglyceride-Glucose Index and 2-Year Adverse Cardiovascular and Cerebrovascular Events in Patients with Type 2 Diabetes Mellitus Who Underwent Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Data on the relationship between the triglyceride glucose (TyG) index and prognosis after off-pump coronary artery bypass grafting (OPCABG) are limited. This retrospective observational cohort study evaluated the association of the TyG index with prognosis in patients with diabetes mellitus who underwent OPCABG.

METHODS

The TyG index was calculated using the following equation: TyG index = ln (fasting triglyceride level [mg/dL] × fasting glucose level [mg/dL]/2). The primary outcomes included the occurrence of major adverse cardiovascular and cerebrovascular events (MACCEs), which were defined as all-cause death, nonfatal myocardial infarction, nonfatal stroke and symptomatic graft failure. The association between the TyG index and MACCEs was assessed by Cox proportional hazards regression analysis.

RESULTS

A total of 1578 patients with diabetes who underwent OPCABG (mean age, 62.9 ± 8.0 years; men, 72.7%) were enrolled in this study. Over the follow-up of 2 years, 176 patients (11.2%) had at least 1 primary endpoint event. The follow-up incidence of the primary endpoint rose with increasing TyG index tertiles. The multivariate Cox proportional hazards regression analysis adjusted for multiple confounders revealed a hazard ratio for the primary endpoint of 2.133 (95% CI 1.347-3.377; P for trend = 0.001) when the highest and lowest TyG index tertiles were compared.

CONCLUSION

The TyG index was significantly and positively associated with MACCEs, suggesting that the TyG index may be a valuable predictor of adverse cardiovascular and cerebrovascular outcomes after OPCABG in patients with T2DM.

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.

Release Profile of Cardiac Troponin T and Risk Factors of Postoperative Myocardial Injury in Patients Undergoing CABG

Background

Cardiac troponin T (cTnT) is currently one of the important indicators for clinical diagnosis of myocardial injury, which is inevitable in cardiac surgery, especially coronary artery bypass grafting (CABG). Describing the release profile of cTnT and finding out the risk factors of postoperative myocardial injury (PMI) are of great significance. The purposes of this study are to explore the release profile of cTnT in patients undergoing CABG and to search for independent risk factors of PMI.

Methods

In this retrospective study, clinical data of CABG patients were collected. The cTnT was measured at 24 hours before and 6, 12, 24, 48, 72, 96 and 120 hours after operation separately. The release profiles and peak time of cTnT in total cohort and sub-cohorts were observed. Independent risk factors of PMI were explored via univariate and multivariate logistic regression analyses.

Results

In total, 2084 patients were enrolled, including 998 patients in a cTnT group and 1086 patients in a high-sensitive cTnT (hs-cTnT) group. PMI was recognized in 797 patients. In both groups, cTnT showed a trend of rising first and then falling within 120 hours after operation. The peak cTnT appeared within 12–24 hours after operation, while the peak hs-cTnT occurred mostly within 24–48 hours after operation. Univariate logistic analysis showed that body mass index (BMI), New York Heart Association (NYHA) classification, coronary artery disease (CAD) classification, cerebrovascular disease, left ventricular ejection fraction, number of diseased vessels, valvular disease, intra-aortic balloon pump (IABP) implantation, chronic obstructive pulmonary disease, pulmonary hypertension, previous percutaneous coronary intervention (PCI), BMI, bypass graft number, cardiopulmonary bypass, and preoperative cTnT were related risk factors. Multivariate logistic regression analysis showed that NYHA classification, CAD classification, valvular disease, IABP implantation, pulmonary hypertension, previous PCI, bypass graft number, cardiopulmonary bypass, and preoperative cTnT were independent risk factors of PMI.

Conclusion

NYHA classification, CAD classification, valvular disease, IABP implantation, pulmonary hypertension, previous PCI, bypass graft number, cardiopulmonary bypass, and preoperative cTnT are independent risk factors of PMI in patients undergoing CABG.

Predictive ability of EuroSCORE II integrating cardiactroponin T in patients undergoing OPCABG

Background

Preoperative risk evaluation systems are significant and important to the allocation of medical resources and the communication between doctors and patients. The European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) is widely used in clinical practice. Cardiac troponin T (cTnT) can specifically and accurately reflect myocardial injury. Whether EuroSCORE II can improve the predictive power after integrating with cTnT is still unclear. This study was a retrospective single center study designed to assess the predictive ability of EuroSCORE II integrated with cTnT for patients undergoing isolated off-pump coronary artery bypass grafting (OPCABG).

Methods

This retrospective and observational cohort study included 1887 patients who underwent first isolated OPCABG. cTnT was detected within 48 h before operation in each patient. According to myocardial injury, patients were divided by cTnT into 4 stages. A new risk evaluation system was created through logistic regression with EuroSCORE II and myocardial injury classification as covariates. Then the two risk evaluation systems were comparatively assessed by regression analysis, receiver operator characteristic curves, net reclassification index, Bland–Altman plots and decision curve analysis.

Results

There were 43 in-hospital deaths, with a mortality of 2.30% (43/1887). The logistic regression analysis showed that preoperative myocardial injury classification was a significant risk factor for in-hospital mortality in both total cohort (OR 1.491, 95%CI 1.049–2.119) and subsets (OR 1.761, 95%CI 1.102–2.814). The new risk evaluation system has higher calibration and discrimination power than EuroSCORE II, both for overall cohort and subsets. Especially, the new system has obvious advantages in discrimination power in the subset of acute myocardial infarction (AUC 0.813 vs. 0.772, 0.906 vs. 0.841, and 0.715 vs. 0.646, respectively).

Conclusions

Both myocardial injury classification and EuroSCORE II are independent risk factors of in-hospital mortality in OPCABG patients. The new risk evaluation system has higher predictive ability than EuroSCORE II, especially in patients with a recent history of AMI.

Retractor in retractor technique

Placing retractor and stabilization devices during open heart surgery can be difficult in obese patients due to extremely short neck and excessive breast tissue. Off-pump coronary bypass operations in these patients can be particularly technically demanding. To overcome this difficulty, we have used two retractors concomitantly. The first retractor is placed to the edges of sternum and the second one is placed into this first retractor. This maneuver ensures an extra height, and placing stabilization devices in this second retractor is relatively easy. Thus, we suggest that adding this maneuver will facilitate off-pump coronary bypass operations.