Beating-heart on-pump coronary artery bypass grafting vs. off-pump coronary artery bypass grafting: a systematic review and meta-analysis

Case Report: Staged surgical management in ESRD: off-pump CABG followed by renal transplantation to enhance graft survival

Patients with end-stage renal disease face a significantly higher risk of cardiovascular diseases. For patients who are candidates for renal transplantation (RT), major surgeries such as coronary artery bypass grafting (CABG) are associated with cardiac complications as well as higher rates of post-operative complications, including the need for large amounts of blood transfusion, worsening kidney function, infection, and graft rejection. Studies have shown that blood transfusions can increase the risk of graft rejection due to immune system activation. Off-pump CABG (OPCAB), also known as beating heart surgery, is a technique in which a heart-lung machine is not used, and the heart continues to beat throughout the procedure. The main advantage of OPCAB surgery compared to on-pump CABG (ONCAB) is that it requires fewer blood product transfusions and has fewer renal, pulmonary, and hematological complications. This case series uniquely discusses two patients who underwent successful beating heart CABG without blood transfusion, followed by RT.

Survival and Mid-Term Outcomes of On Pump vs. Off Pump Coronary Artery Bypass Grafting: A Propensity Score-Matched Analysis in A First Peruvian Registry

INTRODUCTION

The efficacy and outcomes of on-pump and off-pump coronary artery bypass grafting (CABG) remain uncertain, especially in Latin America. Our study aims to explore survival and shortand mid-term outcomes in the first reported Peruvian registry of patients treated with both techniques.

METHODS

This is an observational, analytical, and longitudinal study using a propensity score-matched (PSM) analysis in a single-center retrospective registry of 2280 patients during 2000-2019; 846 patients were analyzed after PSM (on-pump = 423 vs. off-pump = 423). Baseline variables, comorbidities, and major outcomes were studied in the short term (≤ 30 days) and in midterm (30 days-36 months) with major adverse cardiac and cerebrovascular events. The matched groups were compared by descriptive, multivariate, and Kaplan-Meier survival analyses.

RESULTS

Before PSM, previous myocardial infarction < 7 days (27.03%) and ejection fraction ≥ 50% (45.72%) were higher in off-pump CABG (P<0.05). After PSM, pre-surgery percutaneous coronary intervention (27.18% vs. 26.71%, P=0.049) and Society of Thoracic Surgeons risk score (1.98% vs. 1.90%, P=0.047) were higher in off-pump CABG. In the short term, there was higher mortality (2.12% vs. 0.47%, P=0.048), blood transfusion > 500 ml (57.91% vs. 7.56%, P=0.049), reintervention (7.32% vs. 2.12%, P=0.045), hospital stay (nine vs. four days, P=0.048), arrhythmia (9.92% vs. 4.96%, P=0.049), and renal failure (20.09% vs. 5.91%, P=0.009) in on-pump CABG. Long-term mortality (4.25% vs. 1.65%, P=0.044), myocardial infarction (17.02% vs. 7.32%, P=0.046), and repeat revascularization (17.49% vs. 8.26%, P=0.045) predominated in on-pump CABG. There was a higher 36-month adjusted survival for off-pump over on-pump CABG (97.88% vs. 93.63%, P=0.046).

CONCLUSION

This first reported Peruvian registry of patients treated with CABG has demonstrated that off-pump CABG is associated with lower shortand mid-term morbidity and mortality rates and better-adjusted survival rates compared to on-pump CABG; however, further multicenter studies in Latin America are needed to elucidate its benefits over classic on-pump CABG.

Left Ventricular Systolic Function Changes During Pump-Assisted Beating Heart Coronary Artery Bypass Graft Surgery: A Prospective Observational Study

BACKGROUND

There is a lack of information about the left ventricle (LV) systolic function changes during pump-assisted beating heart coronary artery bypass graft surgery (PACAB). This study aimed to study the changes in LV systolic function changes during PACAB.

METHODS

In this prospective, single-arm, observational study, 70 patients with American Society of Anesthesiologists physical status III or IV of either sex, aged 40-70 years, scheduled to undergo elective PACAB for isolated ischemic heart disease with EF >30% were included. We excluded patients with pregnancy, pericardial effusion, contraindications to transesophageal echocardiography (TEE), regional wall-motion abnormality of basal LV segments, pericardial effusion, right ventricular dysfunction, bundle branch blocks, and atrial fibrillation. After standard anesthesia induction, patients underwent PACAB. LV ejection fraction (EF), mitral annular plane systolic excursion (MAPSE), and tissue Doppler-derived peak mitral annular systolic velocity (s') were recorded at various time points of surgery. Change in LV EF during surgery was the primary outcome variable of the study. Secondary outcome variables were complications and changes in MAPSE and s'. A repeated measure analysis of variance was used to compare the changes in LV systolic function at various stages of surgery.

RESULTS

Baseline LV EF was 47.73±9.91%. Compared to baseline, changes in EF during and after the surgery were not statistically and clinically significant. Changes in MAPSE and s' during the surgery were not statistically significant. Complications included postoperative acute kidney injury, stroke, excess bleeding, and pneumonia.

CONCLUSION

LV systolic function does not vary significantly during PACAB. However, more extensive randomized trials are required to apply these findings for routine use.

Effectiveness of Dexamethasone in Reducing Arrhythmia in Patients Undergoing Coronary Artery Bypass Grafting

Introduction Coronary artery bypass grafting (CABG) carries the risk of postoperative arrhythmias. Our study focusses on the efficacy of dexamethasone in both on-pump CABG (ONCAB) and off-pump CABG (OPCAB). Methods This single center randomized control trial was conducted from July 1st, 2018 to January 20th, 2019 in patients undergoing conventional ONCAB and OPCAB at the National Cardiovascular Center Harapan Kita (NCCHK). All arrhythmia incidents were recorded postoperatively with routine monitoring done every hour until the patient was discharged. Results One hundred and twenty patients were included in the study and arrhythmias occurred in 24.2% of patients. In the ONCAB groups, there was an association between dexamethasone versus placebo in reducing the incidence of arrhythmias (p = 0.02; OR 0.23 [0.064-0.831]). However, in patients who underwent OPCAB, there was no association between dexamethasone administration and the incidence of arrhythmias (p = 0.347; OR 0.55 [0.157-1.931]). Patients on dexamethasone in both ONCAB and OPCAB groups showed a significant decrease in IL-6, CRP, and procalcitonin (p = 0.001 for all). Overall, arrhythmic subjects had significantly higher levels of inflammatory markers IL-6 (p = 0.013), CRP (p = 0.025), and procalcitonin (p = 0.001). Conclusion Dexamethasone reduced postoperative arrhythmias, likely by modulating systemic inflammation, as shown by the decrease in inflammatory markers in ONCAB patients compared to those given a placebo.

Comparison between Off-Pump and On-Pump Beating Heart Coronary Artery Bypass Grafting

BACKGROUND

 Although coronary artery bypass grafting (CABG) is performed via three different techniques, conventional, on-pump beating heart CABG (ONBHCAB), or off-pump CABG (OPCAB), data are limited to compare ONBHCAB with OPCAB.

METHODS

 We retrospectively investigated the postoperative cardiac biomarkers, creatine kinase-MB (CK-MB), and troponin I (cTnI), and early and late outcomes in 806 patients undergoing isolated ONBHCAB or OPCAB between February 2008 and September 2022. To eliminate the bias between different groups, propensity score matching was conducted to validate the findings.

RESULTS

 After matching, the number of each study group totaled 270 patients. In both complete and matched cohorts, early outcomes, including morbidities and mortalities, were similar. However, cTnI and CK-MB levels were significantly higher after ONBHCAB than after OPCAB with median peak cTnI of 9.85 versus 4.60 ng/mL and median peak CK-MB of 48.45 versus 17.10 ng/mL in the matched cohort, which were quite low, below the threshold for values defining perioperative myocardial infarction. At follow-up of 73 ± 45 months, the overall actuarial survival rates were similar between the ONBHCAB and OPCAB patients (86 vs. 87% at 5 years and 64 vs. 68% at 10 years, respectively, in the matched cohort).

CONCLUSION

 ONBHCAB may be a comparable alternative to OPCAB with similar early and late outcomes, despite higher elevation of postoperative cardiac biomarkers. ONBHCAB provides more efficient hemodynamic support, providing a better surgical visual field, than OPCAB while reducing the risk of incomplete revascularization.

Construction and validation of a risk prediction model for postoperative delirium in patients with off‑pump coronary artery bypass grafting

Background

Compared with cardiopulmonary bypass surgery, off-pump coronary artery bypass grafting (OPCABG) reduces trauma to the body. However, there is still a risk of neurological complications, including postoperative delirium (POD). To date, few studies have been conducted on the risk of POD in OPCABG patients, and no standardized prediction model has been established. Thus, this study sought to analyze the factors influencing POD in OPCABG patients and to construct a risk prediction model.

Methods

A total of 1,258 patients with OPCABG were enrolled and divided into the training set for model construction (944 cases) and the test set for model validation (314 cases). A risk prediction model for POD in OPCABG patients was established by least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression, and a nomogram was drawn. The discrimination and calibration degree of the model was evaluated by the receiver operator characteristic (ROC) curve and calibration curve.

Results

Eight variables [i.e., age, tissue oxygen saturation, mean arterial pressure (MAP), carotid stenosis, the anterior-posterior diameter of the aortic sinus, ventricular septum thickness, left ventricular ejection fraction (LVEF), and Mini-Mental State Examination (MMSE) scores] were screen out by the LASSO regression and multivariate logistic regression, and the model was constructed. The area under the ROC curve of the training set was 0.702 [95% confidence interval (CI): 0.662-0.743], and that of the test set was 0.658 (95% CI: 0.585-0.730). The results of the Hosmer-Lemeshow goodness-of-fit test showed that the predicted POD risk of OPCABG patients in the training and test sets was consistent with the actual POD risk (χ2=5.154, P=0.74).

Conclusions

The occurrence of POD in OPCABG patients is related to age, tissue oxygen saturation, MAP, carotid artery stenosis, the anterior-posterior diameter of aortic sinus, ventricular septal thickness, LVEF, and MMSE scores. The prediction model constructed with the above variables had high predictive performance, and thus may be helpful in the early identification of such patients.

Short-term and long-term outcomes of on-pump beating-heart coronary artery bypass surgery in dialysis and non-dialysis patients: a retrospective study in a single center

BACKGROUND

This study aimed to evaluate the short-term and long-term outcomes of dialysis and non-dialysis patients after On-pump beating-heart coronary artery bypass grafting (OPBH-CABG).

METHODS

We retrospectively reviewed medical records of 659 patients underwent OPBH-CABG at our hospital from 2009 to 2019, including 549 non-dialysis patients and 110 dialysis patients. Outcomes were in-hospital mortality, length of stay, surgical complications, post-CABG reintervention, and late mortality. The median follow-up was 3.88 years in non-dialysis patients and 2.24 years in dialysis patients. Propensity matching analysis was performed.

RESULTS

After 1:1 matching, dialysis patients had significantly longer length of stay (14 (11-18) vs. 12 (10-15), p = 0.016), higher rates of myocardial infarction (16.85% vs. 6.74%, p = 0.037) and late mortality (25.93% vs. 9.4%, p = 0.005) after CABG compared to non-dialysis patients. No significant differences were observed in in-hospital mortality, complications, or post-CABG reintervention rate between dialysis and non-dialysis groups.

CONCLUSIONS

OPBH-CABG could achieve comparable surgical mortality, surgical complication rates, and long-term revascularization in dialysis patients as those in non-dialysis patients. The results show that OPBH-CABG is a safe and effective surgical option for dialysis patients.

Comparative efficacy on outcomes of C-CABG, OPCAB, and ONBEAT in coronary heart disease: a systematic review and network meta-analysis of randomized controlled trials

IMPORTANCE

Coronary artery bypass grafting (CABG) remains the gold standard for the treatment of multivessel and left main coronary heart disease. However, the current evidence about the optimal surgical revascularization strategy is inconsistent and is not sufficient to allow for definite conclusions. Thus, this topic needs to be extensively discussed.

OBJECTIVE

The aim of this present study was to compare the clinical outcomes of off-pump CABG (OPCAB), conventional on-pump CABG (C-CABG), and on-pump beating heart (ONBEAT) CABG via an updated systematic review and network meta-analysis of randomized controlled trials.

DATA SOURCES

PubMed, Web of Science, and the Cochrane Central Registry were searched for relevant randomized controlled trials that were published in English before 1 December 2021.

STUDY SELECTION

Published trials that included patients who received OPCAB, C-CABG, and ONBEAT CABG were selected.

DATA EXTRACTION AND SYNTHESIS

Two authors independently screened the search results, assessed the full texts to identify eligible studies and the risk of bias of the included studies, and extracted data. All processes followed the Preferred Reporting Items for Systematic Review and Meta-analysis of Individual Participant Data.

MAIN OUTCOMES AND MEASURES

The primary outcome was postoperative mortality in patients who underwent C-CABG, OPCAB, or ONBEAT CABG. The secondary outcomes were postoperative myocardial infarction, stroke, and renal impairment in the three groups. The time point for analysis of outcomes was all time periods during the postoperative follow-up.

RESULTS

A total of 39 385 patients (83 496.2 person-years) in 65 studies who fulfilled the prespecified criteria were included. In the network meta-analysis, OPCAB was associated with an increase of 12% in the risk of all-cause mortality when compared with C-CABG [odds ratio (OR): 1.12; 95% CI: 1.04-1.21], a reduction of 49% in the risk of myocardial infarction when compared with ONBEAT (OR: 0.51; 95% CI: 0.26-0.99), a reduction of 16% in the risk of stroke when compared with C-CABG (OR: 0.84; 95% CI: 0.72-0.99) and a similar risk of renal impairment when compared with C-CABG and ONBEAT.

CONCLUSIONS AND RELEVANCE

OPCAB was associated with higher all-cause mortality but lower postoperative stroke compared with C-CABG. OPCAB was associated with a lower postoperative myocardial infarction than that of ONBEAT. Early mortality was comparable among OPCAB, ONBEAT, and C-CABG.