Outcomes of off-pump versus on-pump coronary artery bypass grafting: Impact of preoperative risk

Less Invasive and Hybrid Surgical/Interventional Coronary Disease Management: The Future Is Now

Coronary artery bypass grafting (CABG) has evolved to become the criterion standard in elective revascularisation for coronary artery disease (CAD), particularly in patients with complex or multivessel CAD, left main involvement, diabetes mellitus, or left ventricular dysfunction. Despite the superiority of CABG in patients with the most advanced forms of CAD, a standard CABG operation, through a median sternotomy and with the use of cardiopulmonary bypass, carries well recognised challenges. In this article, we describe newer approaches, such as off-pump CABG, minimally invasive bypass grafting, robotic CABG, and hybrid coronary revascularisation, which we consider as necessary ways to minimise invasion, reduce recovery time, provide the benefits of arterial grafting to more patients, and offer alternatives to mitigate the adverse effects of conventional sternotomy and cardiopulmonary bypass.

On- vs. Off-Pump CABG in Heart Failure Patients with Reduced Ejection Fraction (HFrEF): A Multicenter Analysis

OBJECTIVE

This study aimed to compare postoperative outcomes and 30-day mortality in patients with reduced ejection fraction (<40%) who underwent isolated coronary artery bypass grafting (CABG) with (ONCAB) and without (OPCAB) the use of cardiopulmonary bypass.

METHODS

data from four university hospitals in Germany, spanning from January 2017 to December 2021, were retrospectively analyzed. A total of 551 patients were included in the study, and various demographic, intraoperative, and postoperative data were compared.

RESULTS

demographic parameters did not exhibit any differences. However, the OPCAB group displayed notably higher rates of preoperative renal insufficiency, urgent surgeries, and elevated EuroScore II and STS score. During surgery, the ONCAB group showed a significantly higher rate of complete revascularization, whereas the OPCAB group required fewer intraoperative transfusions. No disparities were observed in 30-day/in-hospital mortality for the entire cohort and the matched population between the two groups. Subsequent to surgery, the OPCAB group demonstrated significantly shorter mechanical ventilation times, reduced stays in the intensive care unit, and lower occurrences of ECLS therapy, acute kidney injury, delirium, and sepsis.

CONCLUSIONS

the study's findings indicate that OPCAB surgery presents a safe and viable alternative, yielding improved postoperative outcomes in this specific patient population compared to ONCAB surgery. Despite comparable 30-day/in-hospital mortality rates, OPCAB patients enjoyed advantages such as decreased mechanical ventilation durations, shorter ICU stays, and reduced incidences of ECLS therapy, acute kidney injury, delirium, and sepsis. These results underscore the potential benefits of employing OPCAB as a treatment approach for patients with coronary heart disease and reduced ejection fraction.

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.

Euvolemic off pump coronary surgery further improves early postoperative outcomes

Background:

Fluid resuscitation during Off-Pump Coronary Surgery (OPCABG) is still not protocolized and depends on multiple variables. We are exploring in this study whether a restrictive or euvolemic approach has any impact on short term surgical outcomes following OPCABG.

Methods:

It is a retrospective study of 300 patients analyzed based on the intraoperative fluid requirement with 150 patients in each group (Group I: Fluid <2 Litres, Group II: Fluid >2 Litres).

Results:

Multivariable analysis showed echocardiography variables such as E/e ratio, LA volume index, and atrial fibrillation (AF). LA volume index is related to the higher fluid requirement. Group II had significantly higher ventilation time (P < 0.05), drain output (P = 0.05), drain removal time (<0.05), inotropic requirement, and diuretic use.

Conclusion:

The requirement of the intraoperative fluid was associated with various factors including diastolic dysfunction (left atrial volume index, left ventricle mass index, E/e ratio) and preoperative dual antiplatelet use. Group II patients had longer ventilation time, diuretics use, high drain output, and required drains for a longer period of time. Although there was no statistical difference among two groups as far as postoperative AF concerned, a reversal of AF to sinus rhythm was delayed in group II patients.

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.

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.

Preoperative right ventricular dysfunction requires high vasoactive and inotropic support during off-pump coronary artery bypass grafting

Objectives

The association of preoperative RV function with hemodynamics during OPCAB or emergency conversion is not clear. The aim of this study was to investigate the association of vasoactive-inotropic score with tricuspid annular plane systolic excursion and tricuspid regurgitation in off-pump coronary artery bypass grafting, and to calculate the optimal cut-off value of tricuspid annular plane systolic excursion to predict emergency conversion to cardiopulmonary bypass.

Methods

Patients over 20 years of age who had undergone off-pump coronary artery bypass grafting between April 2015 and March 2020 were enrolled in this study. We retrospectively assessed the association of intraoperative maximum “vasoactive-inotropic score”, a weighted sum of various inotropes and vasoconstrictors, with tricuspid annular plane systolic excursion and tricuspid regurgitation. A receiver operating characteristic curve of conversion on tricuspid annular plane systolic excursion was also constructed.

Results

135 patients were included in final analysis. Conversion was performed in 10 cases. Multiple regression analysis showed that tricuspid annular plane systolic excursion, mild or more tricuspid regurgitation and experienced surgeon were significantly related to vasoactive-inotropic score. The receiver operating characteristic curve to predict conversion by tricuspid annular plane systolic excursion showed an optimal cut-off value of 15.0 mm and area under the curve of 0.808.

Conclusions

Tricuspid annular plane systolic excursion and tricuspid regurgitation were associated with vasoactive-inotropic score in off-pump coronary artery bypass grafting. The optimal cut-off value of tricuspid annular plane systolic excursion to predict emergency conversion was 15 mm.

Current Impact of Cardiopulmonary Bypass in Coronary Artery Bypass Grafting in São Paulo State

BACKGROUND

Previous results on the use of cardiopulmonary bypass (CPB) have generated difficulties in choosing the best treatment for each patient undergoing myocardial revascularization surgery (CABG) in the current context.

OBJECTIVE

Evaluate the current impact of CPB in CABG in São Paulo State.

METHODS

A total of 2905 patients who underwent CABG were consecutively analyzed in 11 São Paulo State centers belonging to the São Paulo Registry of Cardiovascular Surgery (REPLICCAR) I. Perioperative and follow-up data were included online by trained specialists in each hospital. Associations of the perioperative variables with the type of procedure and with the outcomes were analyzed. The study outcomes were morbidity and operative mortality. The expected mortality was calculated using EuroSCORE II (ESII). The values of p <5% were considered significant.

RESULTS

There were no significant differences concerning the patients' age between the groups (p=0.081). 72.9% of the patients were males. Of the patients, 542 underwent surgery without CPB (18.7%). Of the preoperative characteristics, patients with previous myocardial infarction (p=0.005) and ventricular dysfunction (p=0.031) underwent surgery with CPB. However, emergency or New York Heart Association (NYHA) class IV patients underwent surgery without CPB (p<0.001). The ESII value was similar in both groups (p=0.427). In CABG without CPB, the radial graft was preferred (p<0.001), and in CABG with CPB the right mammary artery was the preferred one (p<0.001). In the postoperative period, CPB use was associated with reoperation for bleeding (p=0.012).

CONCLUSION

Currently in the REPLICCAR, reoperation for bleeding was the only outcome associated with the use of CPB in CABG. (Arq Bras Cardiol. 2020; 115(4):595-601).

Effects of Minimal Extracorporeal Circulation on the Systemic Inflammatory Response and the Need for Transfusion after Coronary Bypass Grafting Surgery

Objectives

The aim of this study is to compare the effects of the minimal extracorporeal circulation (MiECT) on postoperative systemic inflammatory response and the need for transfusion in patients undergoing open heart surgery with cardiopulmonary bypass.

Methods

Patients were divided into two groups; Group M (n=31) included the patients operated via using the MiECT system and Group C (n=27) included the patients operated via using conventional cardiopulmonary bypass (CPB). Perioperative markers of inflammation after cardiopulmonary bypass in both groups were tested by measuring the levels via chemiluminescent immunometric assay. Blood samples were taken consecutively after anesthesia induction, 30^th minute of CPB, on the 6^th, 24^th, and 48^th hours after cardiopulmonary bypass.

Results

The mean amount of priming solution was significantly lower in Group M when compared to Group C (802.60 ± 48.26 and 1603.71 ± 49.85 ml). The mean hematocrit (Hct) value taken immediately after cardiopulmonary bypass was found to be significantly higher in the MiECT patients with respect to the other group (% 32.71 ± 3.98 and % 28.82 ± 4.39). The transfused amounts of erythrocyte suspension and fresh frozen plasma were found to be significantly lower in patients in Group M when compared to those in Group C. Postoperative mediastinal drainage was also significantly lower in patients in Group M with respect to the other group. There was no significant difference between markers of inflammation.

Conclusion

Our results show that MiECT seems to be more advantageous in terms of priming volume, perioperative hematocrit levels, need for blood and blood product transfusion, and mediastinal drainage with respect to the conventional approach after coronary artery bypass grafting.

Comparison of Outcomes for Off-Pump Versus On-Pump Coronary Artery Bypass Grafting in Low-Volume and High-Volume Centers and by Low-Volume and High-Volume Surgeons

In terms of in-hospital outcomes, controversy still remains whether off-pump coronary artery bypass grafting is superior to on-pump coronary artery bypass surgery. We investigated whether the volume of off-pump coronary artery bypass procedures by hospital and individual surgeon influences patient outcomes when compared with on-pump coronary artery bypass surgery. Discharge records from the Nationwide Inpatient Sample were retrospectively reviewed for in-hospital admissions from 2003 to 2011, including 999 hospitals in 44 states. A total of 2,094,094 patients undergoing on- and off-pump coronary artery bypass surgery were included. In patients requiring 2 or more grafts, off-pump coronary artery bypass compared with on-pump coronary artery bypass was associated with increased risk-adjusted mortality when performed in low-volume centers (<29 cases per year) (odds ratio [OR] 1.32, 95% confidence interval [CI] 1.06 to 1.57) or by low-volume surgeons (<19 cases per year) (OR 1.26, 95% CI 1.02 to 1.56). In high-volume off-pump coronary artery bypass centers (≥164 cases per year) and surgeons (≥48 cases per year), off-pump coronary artery bypass reduced mortality compared with on-pump coronary artery bypass in cases requiring a single graft (OR 0.66, 95% CI 0.49 to 0.89 and OR 0.33, 95% CI 0.22 to 0.47, respectively) or 2 or more grafts (OR 0.82, 95% CI 0.66 to 0.99 and OR 0.63, 95% CI 0.49 to 0.81, respectively). In conclusion, the outcome of off-pump coronary artery bypass grafting procedures is dependent on volume at both the institution and the individual surgeon level. Off-pump coronary artery bypass should not be performed at low-volume centers and by low-volume surgeons.

Off-pump versus On-pump Coronary Artery Bypass Grafting in Frail Patients: Study Protocol for the FRAGILE Multicenter Randomized Controlled Trial

Introduction

Advances in modern medicine have led to people living longer and healthier lives. Frailty is an emerging concept in medicine yet to be explored as a risk factor in cardiac surgery. When it comes to CABG surgery, randomized controlled clinical trials have primarily focused on low-risk (ROOBY, CORONARY), elevated-risk (GOPCABE) or high-risk patients (BBS), but not on frail patients. Therefore, we believe that off-pump CABG could be an important technique in patients with limited functional capacity to respond to surgical stress. In this study, the authors introduce the new national, multicenter, randomized, controlled trial "FRAGILE", to be developed in the main cardiac surgery centers of Brazil, to clarify the potential benefit of off-pump CABG in frail patients.

Methods

FRAGILE is a two-arm, parallel-group, multicentre, individually randomized (1:1) controlled trial which will enroll 630 patients with blinded outcome assessment (at 30 days, 6 months, 1 year, 2 years and 3 years), which aims to compare adverse cardiac and cerebrovascular events after off-pump versus on-pump CABG in pre-frail and frail patients. Primary outcomes will be all-cause mortality, acute myocardial infarction, cardiac arrest with successful resuscitation, low cardiac output syndrome/cardiogenic shock, stroke, and coronary reintervention. Secondary outcomes will be major adverse cardiac and cerebrovascular events, operative time, mechanical ventilation time, hyperdynamic shock, new onset of atrial fibrillation, renal replacement therapy, reoperation for bleeding, pneumonia, length of stay in intensive care unit, length of stay in hospital, number of units of blood transfused, graft patency, rate of complete revascularization, neurobehavioral outcomes after cardiac surgery, quality of life after cardiac surgery and costs.

Discussion

FRAGILE trial will determine whether off-pump CABG is superior to conventional on-pump CABG in the surgical treatment of pre-frail and frail patients.

Trial registration

ClinicalTrials.gov, ID: NCT02338947. Registered on August 29^th 2014; last updated on March 21^st 2016.

The evolution of minimally invasive cardiac surgery: from minimal access to transcatheter approaches

The field of minimally invasive cardiac surgery has undergone rapid transformation over recent years. In this review, we provide a summary of the most current evidence supporting the use of minimally invasive aortic and mitral valve replacement techniques, as well as transcatheter approaches for aortic and mitral valve disease. As an adjunct, the use of robotically assisted coronary bypass surgery and hybrid coronary revascularization procedures is discussed. In order to obtain optimal patient outcomes, a collaborative, heart-team approach between cardiac surgeons and interventional cardiologists is necessary.

Efficacy and effectiveness of on- versus off-pump coronary artery bypass grafting: A meta-analysis of mortality and survival

BACKGROUND

Despite many studies comparing on- versus off-pump coronary artery bypass graft (CABG), there is no consensus as to whether one of these techniques offers patients better outcomes.

METHODS

We searched PubMed from inception to June 30, 2015, and identified additional studies from bibliographies of meta-analyses and reviews. We identified 42 randomized controlled trials (RCTs) and 31 rigorously adjusted observational studies (controlling for the Society of Thoracic Surgeons-recognized risk factors for mortality) reporting mortality for off-pump versus on-pump CABG at specified time points. Trial data were extracted independently by 2 researchers using a standardized form. Differences in probability of mortality (DPM) were estimated for the RCTs and observational studies separately and combined, for time points ranging from 30 days to 10 years.

RESULTS

RCT-only data showed no significant differences at any time point, whereas observational-only data and the combined analysis showed short-term mortality favored off-pump CABG (n = 1.2 million patients; 36 RCTs, 26 observational studies; DPM [95% confidence interval (CI)], -44.8% [-45.4%, -43.8%]) but that at 5 years it was associated with significantly greater mortality (n = 60,405 patients; 3 RCTs, 5 observational studies; DPM [95% CI], 10.0% [5.0%, 15.0%]). At 10 years, only observational data were available, and off-pump CABG showed significantly greater mortality (DPM [95% CI], 14.0% [11.0%, 17.0%]).

CONCLUSIONS

Evidence from RCTs showed no differences between the techniques, whereas rigorously adjusted observational studies (with >1.1 million patients) and the combined analysis indicated that off-pump CABG offers lower short-term mortality but poorer long-term survival. These results suggest that, in real-world settings, greater operative safety with off-pump CABG comes at the expense of lasting survival gains.

The future of off-pump coronary artery bypass grafting: a North American perspective

Off-pump coronary artery bypass graft (OPCAB) is currently performed routinely in a minority of specialized centers and in many more centers, utilized only when a porcelain aorta mandates a no-touch aortic technique. The OPCAB literature can be summarized as follows: (I) large-scale randomized trials in relatively low risk patients that include surgeons with a range of experience demonstrating no consistent beneficial differences in major cardiovascular and cerebrovascular outcomes but lower transfusion rates and shorter length of stay, tempered by some reports of higher rates of incomplete revascularization and lower rates of long term graft patency; (II) smaller randomized controlled trials (RCTs) from highly specialized programs demonstrating equivalent or superior outcomes with OPCAB and similar completeness of revascularization and graft patency; and (III) observational data from large databases demonstrating a consistent benefit of OPCAB, especially in higher-risk patient subsets. Our rationale for OPCAB remains that if complete and precise revascularization can be safely and routinely accomplished, then the patient should benefit by avoiding the morbidities that can be attributed to aortic cannulation/clamping, cardiopulmonary bypass (CPB), hemodilution, hypothermia and global myocardial ischemia/cardioplegia. We further believe that OPCAB procedures should emphasize the use of arterial grafts to optimize long term patency and minimize aortic manipulation to limit the risk of stroke. Moving forward, the off-pump surgical community and specialty societies must address the challenge of training surgeons and their teams to master this technically demanding procedure. Furthermore, OPCAB opens the door to minimally-invasive surgical revascularization via hybrid coronary revascularization (HCR). A large NIH-funded RCT is currently underway to determine whether hybrid revascularization can offer a superior alternative to multi-vessel percutaneous coronary intervention for patients with low SYNTAX score and proximal LAD disease.

Short-term clinical outcomes after off-pump coronary artery bypass grafting at a single Veterans Affairs Medical Center

Background

We retrospectively assessed the outcomes after coronary revascularization at a single Veterans Affairs Medical Center when a strategy of assigning higher risk patients to off-pump coronary artery bypass grafting (CABG) was employed.

Methods

Over a 5 year period all consecutive patients that underwent CABG at our VA Medical Center were assigned to a surgeon who either performs the CABG exclusively off-pump or to one who performed the CABG on-pump. The higher risk patients were assigned preferentially for off-pump revascularization. VASQIP (VA Hospitals Surgical Quality Improvement Program) data between 10/2007 and 12/2012 were retrospectively reviewed at our VA Medical Center and the short term outcomes were assessed.

Results

A total of 252 consecutive patients underwent off-pump CABG (n = 170) and on-pump CABG (n = 82). There were significantly more patients with low LVEF (<45 %; p = 0.008) and cerebrovascular disease in the off-pump group (p = 0.024). The number of patients smoking at the time of surgery was significantly higher in the off-pump group (p = 0.002) as well. The 30-day composite morbidity and mortality was 6 % for all CABG patients and significantly lower with off-pump vs. on-pump CABG (3.5 % vs. 11 %; p = 0.019). There were no conversions from off-pump to on-pump surgery.

Conclusions

A selective strategy to direct higher risk patients towards an off-pump revascularization yielded favorable outcomes in an unselected veteran population treated at a single VA Medical Center over a 5 year period.

Developments in surgical revascularization to achieve improved morbidity and mortality

Coronary artery bypass graft surgery remains the main treatment modality for multivessel coronary artery disease and has consistently been demonstrated to have significantly lower rates of major adverse cardiac and cerebrovascular events in comparison to percutaneous coronary intervention. In this article we will explore the advances over time and the recent refinements in the techniques of surgical revascularization and how these contribute to the superior outcome profile associated with coronary artery bypass graft surgery. These include the current outcome status of coronary artery bypass grafting; the major landmark trials, registries and meta-analyses comparing coronary artery bypass grafting and percutaneous coronary intervention; the developments in coronary artery disease lesion classification; the techniques for the physiological assessment of coronary artery lesions; bypass grafting using arterial conduits; the role of off-pump coronary artery surgery; the outcomes of reoperative surgery; hybrid techniques for coronary revascularization; minimally invasive coronary artery surgery and finally robotic surgery.

ISMICS Consensus Conference and Statements of Randomized Controlled Trials of Off-Pump versus Conventional Coronary Artery Bypass Surgery

Objective

At this consensus conference, we developed evidence-informed consensus statements and recommendations on the practice of off-pump coronary artery bypass graft (OPCAB) by systematically reviewing and performing meta-analysis of the randomized controlled trials (RCTs) comparing OPCAB and conventional coronary artery bypass (CCAB).

Methods

All RCTs of OPCAB versus CCAB through April 2013 were screened, and 102 relevant RCTs (19,101 patients) were included in a systematic review and meta-analysis (15 RCTs of 9551 high-risk patients; and 87 RCTs of 9550 low-risk patients) in accordance with the Cochrane Collaboration and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology. Consensus statements for the risks and benefits of OPCAB surgery in mortality, morbidity, and resource use were developed based on best available evidence.

Results

Compared to CCAB, it is reasonable to perform OPCAB to reduce risks of stroke [class IIa, level of evidence (LOE) A], renal dysfunction/failure (class IIa, LOE A), blood transfusion (class I, LOE A), respiratory failure (class I, LOE A), atrial fibrillation (class I, LOE A), wound infection (class I, LOE A), ventilation time, and ICU and hospital length of stay (class I, LOE A). However, OPCAB may be associated with a reduced number of grafts performed (class I, LOE A) and with diminished graft patency (class IIa, LOE A, with increased coronary reintervention at 1 year and beyond (class IIa, LOE A), as well as increased mortality at a median follow-up of 5 years (class IIb, LOE A).

Conclusions

OPCAB compared with CCAB may improve outcomes in the short-term (stroke, renal dysfunction, blood transfusion, respiratory failure, atrial fibrillation, wound infection, ventilation time, and length of stay). However, over the longer-term, OPCAB may be associated with reduced graft patency, and increased risk of cardiac re-intervention and death.

On-pump versus off-pump coronary artery bypass surgery in patients with preoperative anemia

OBJECTIVES

The study objective was to evaluate the effects on early outcome and midterm survival of performing coronary artery bypass grafting with the off-pump technique in comparison with cardiopulmonary bypass (on-pump) in patients with preoperative anemia.

METHODS

Consecutive adult anemic patients (preoperative hemoglobin <13.0 g/dL in men and <12.0 g/dL in women) resident in Puglia region who underwent isolated coronary artery bypass grafting between January 2011 and November 2013 were considered. Vital status was ascertained from the date of surgery to December 31, 2013. Odds ratio and hazard ratio (HR) were estimated. Propensity score methods were used to control for confounders.

RESULTS

Of 939 anemic patients (234 female, aged 71 ± 9 years), 361 underwent operation with the off-pump technique and 578 underwent operation with the on-pump technique. Patients undergoing off-pump coronary artery bypass had a shorter intensive care unit length of stay, lower blood transfusion rate, and postoperative reduction in creatinine clearance. During a median follow-up of 18 months, 126 patients died: 46 in hospital (35 on-pump) and 80 after discharge (33 on-pump). In comparison with the off-pump technique, the on-pump technique had greater hospital mortality (odds ratio, 2.57; P = .028) and 30-day incidence of fatal events (HR, 2.67; P = .026). After a period without risk differences between groups (1-6 months; HR, 0.79; P = .618), a lower mortality in those undergoing the on-pump technique was detected (after 6 months HR, 0.35; P = .014). All results were confirmed in the 157 pairs of patients matched for propensity score, anemia grade, and surgery center.

CONCLUSIONS

In patients with low levels of preoperative hemoglobin, off-pump coronary artery bypass was associated with lower early morbidity and mortality but a greater risk of mortality during follow-up compared with on-pump coronary artery bypass.

Sequential vein bypass grafting is not associated with an increase of either in-hospital or mid-term adverse events in off-pump coronary artery bypass grafting

Background:

The impact of sequential vein bypass grafting on clinical outcomes is less known in off-pump coronary artery bypass grafting (CABG). We aimed to evaluate the effects of sequential vein bypass grafting on clinical outcomes in off-pump CABG.

Methods:

From October 2009 to September 2013 at the Fuwai Hospital, 127 patients with at least one sequential venous graft were matched with 127 patients of individual venous grafts only, using propensity score matching method to obtain risk-adjusted outcome comparison. In-hospital measurement was composite outcome of in-hospital death, myocardial infarction (MI), stroke, requirement for intra-aortic ballon pump (IABP) assistance and prolonged ventilation. Major adverse cardiac events (MACEs: Death, MI or repeat revascularization) and angina recurrence were considered as mid-term endpoints.

Results:

No significant difference was observed among the groups in baseline characteristics. Intraoperative mean blood flow per vein graft was 40.4 ml in individual venous grafts groups versus 59.5 ml in sequential venous grafts groups (P < 0.001). There were no differences between individual and sequential venous grafts groups with regard to composite outcome of in-hospital mortality, MI, stroke, IABP assistance and prolonged ventilation (11.0% vs. 14.2%, P = 0.45). Individual in-hospital measurement also did not differ significantly between the two groups. At about four years follow-up, the survival estimates free from MACEs (92.5% vs. 97.3%, P = 0.36) and survival rates free of angina recurrence (80.9% vs. 85.5%, P = 0.48) were similar among individual and sequential venous grafts groups with a mean follow-up of 22.5 months. In the Cox regression analysis, sequential vein bypass grafting was not identified as an independent predictor of both MACEs and angina recurrence.

Conclusions:

Compared to individual vein bypass grafting, sequential vein bypass grafting was not associated with an increase of either in-hospital or mid-term adverse events in patients undergoing off-pump CABG.

Miniaturized extracorporeal circulation versus off-pump coronary artery bypass grafting: a meta-analysis of randomized controlled trials

BACKGROUND

Controversies exist whether off-pump coronary artery bypass (OPCAB) is superior to miniaturized extracorporeal circulation (MECC) in reducing deleterious effects of cardiopulmonary bypass as only a number of smaller randomized controlled trials (RCT) currently provide a limited evidence base. The main purpose of conducting the present meta-analysis was to overcome the expected low power in RCTs in an attempt to establish whether MECC is comparable to OPCAB.

METHODS

A MEDLINE/PubMed search was conducted to identify eligible RCTs. A pooled summary effect estimate was calculated by means of Mantel-Haenszel method.

RESULTS

The search yielded 7 RCTs included in this meta-analysis enrolling 271 patients in the OPCAB group and 279 in the MECC group. The OPCAB and MECC groups were comparable in terms of incidence of in-hospital mortality (Risk Difference [RD] 0.01; 95%CI -0.02, 0.03; P = 0.55; I(2) = 0%), stroke (RD -0.01; 95%CI -0.05, 0.04; P = 0.69; I(2) = 0%), need for renal replacement therapy (RD 0.00; -0.06, 0.06; P = 1; I(2) = 0%), postoperative atrial fibrillation (RD -0.03; -0.17, 0.10; P = 0.64; I(2) = 0%), re-exploration for bleeding (RD -0.01; 95%CI -0.03, 0.02; P = 0.65; I(2) = 0%), transfusion rate (RD -0.01; 95%CI -0.03, 0.02; P = 0.65; I(2) = 0%) and the amount of blood loss (weighted mean difference -25 mL; 95%CI -71, 21; P = 0.28; I(2) = 0%).

CONCLUSIONS

Using a meta-analytic approach, MECC achieves clinical results comparable to OPCAB including postoperative blood loss and blood transfusion requirement. On the basis of our findings, MECC should be considered as a valid alternative to OPCAB in order to reduce surgical morbidity of conventional cardiopulmonary bypass.

Contemporary coronary artery bypass grafting

Current evidence clearly demonstrates that coronary artery bypass grafting (CABG) remains the "gold standard" treatment for most patients with multivessel and left main stem disease. This article summarizes the relevant evidence basis demonstrating that CABG, in comparison to stenting, reduces mortality and subsequent myocardial infarction and the need for repeat revascularization. The article also describes the evidence basis to support the use of more arterial grafts during CABG and the current role of off-pump CABG.

Is the evidence from first time off-pump coronary artery bypass graft surgery transferable to re-operative off-pump surgery?

On-pump coronary artery surgery remains the gold standard treatment for multi-vessel disease. The technique of off-pump surgery has evolved since its first use; however, currently less than 20% of all cases worldwide are performed this way. This poor uptake has been both the cause and the effect of widespread scepticism regarding the validity of the data on the technique, as well as criticism regarding the conversion-related adverse outcomes, graft patency and completeness of revascularisation. Consequently, there has been focus on patient selection from subgroups most likely to benefit from the technique. Re-operative patients, by virtue of their advanced age, complex co-morbidities and the technical challenges of re-operation, fall into this category. In this review, the authors will discuss the outcomes of off-pump surgery in comparison to on-pump, explore the potential beneficial effects of off-pump in re-operative surgery and formulate a decision-making strategy in patients undergoing reoperative coronary artery surgery.

Off-pump coronary surgery: current justifications

Although the literature has failed to project an overall superiority of off-pump vs. on-pump surgery, nevertheless, small randomized control trials and large meta-analysis studies have concluded that the incidence of a stroke is less than 1 % when anaortic off-pump techniques are advocated in patients with diseased ascending aorta. Furthermore, off-pump techniques or their combination with hybrid procedures may lead to a reduction of adverse outcome in the aged high-risk population with concomitant poor left ventricular function and co-morbidities. However, despite this, controversy still exists among the cardiac surgery community in terms of the benefit of this technique and its safety; hence, off-pump is becoming out of fashion. In this review paper, by looking at a "marginal group of patients" (elderly, high risks, atherosclerotic aortas) we attempt to re-establish and justify this technique and re-invent its usage.

Surgical revascularization techniques that minimize surgical risk and maximize late survival after coronary artery bypass grafting in patients with diabetes mellitus

OBJECTIVE

To identify surgical revascularization techniques that minimize surgical risk and maximize late survival in patients with diabetes undergoing coronary artery bypass grafting (CABG).

METHODS

From January 1972 to January 2011, 11,922 patients with diabetes underwent primary isolated CABG. The revascularization techniques investigated included bilateral internal thoracic artery (BITA) grafting (n=938; 7.9%) versus single ITA (SITA) grafting, off-pump (n=602; 5.0%) versus on-pump CABG, and incomplete (n=2109; 18%) versus complete revascularization. The median follow-up was 7.8 years and total follow-up, 104,516 patient-years. Multivariable analyses were performed to assess the effects of surgical techniques on hospital outcomes and long-term mortality.

RESULTS

After adjusting for patient characteristics, BITA versus SITA grafting was associated with a 21% lower late mortality (68% confidence limits, 16%-26%). However, BITA grafting was also associated with more deep sternal wound infections (DSWIs), but the considerable mortality from DSWI minimally affected overall survival because of its rare occurrence. The risk factors for DSWI were female sex (80% increased risk), higher body mass index (7% increased risk per kg/m2), medically treated diabetes (73% increased risk), previous myocardial infarction (58% increased risk), and peripheral arterial disease (73% increased risk). Off-pump and on-pump CABG had similar results. Complete versus incomplete revascularization had similar hospital outcomes; however, complete revascularization was associated with 10% lower late mortality (68% confidence limits, 7.0%-13%).

CONCLUSIONS

BITA grafting with complete revascularization maximizes long-term survival and is recommended for patients with diabetes undergoing CABG. BITA grafting should be used in all patients with diabetes whose risk of DSWI is low. It might be best avoided in obese diabetic women with diffuse atherosclerotic burden-those at greatest risk of developing these infections.