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

Kidney transplantation and cardiomyopathy: Concepts and controversies in clinical decision-making

Increasing comorbidities and an aging population have led to a tremendous increase in the burden of both kidney and cardiac dysfunction. Concomitant cardiomyopathy exposes the patients with kidney disease to further physiological, hemodynamic, and pathologic alterations. Kidney transplantation imposes lesser anesthetic and surgical complexities compared to another solid organ transplant. The surgical decision-making remains an unsettled issue in these conditions. The surgical choices, techniques, and sequences in kidney transplant and cardiac surgery depend on the pathophysiological perturbations and perioperative outcomes. The absence of randomized controlled trials eludes us from suggesting definite management protocol in patients with end-stage kidney disease with cardiomyopathy. Nevertheless, in this review, we extracted data from published literature to understand the pathophysiologic interactions between end-stage renal diseases with cardiomyopathy and also proposed the management algorithm in this challenging scenario. The proposed management algorithm would ensure consensus across all stakeholders involved in decision-making. Our simplistic evidence-based approach would augur future randomized trials and would further ensure refinement in our management approach after the emergence of more definitive evidence.

Analysis of Myocardial Ischemia Parameters after Coronary Artery Bypass Grafting with Minimal Extracorporeal Circulation and a Novel Microplegia versus Off-Pump Coronary Artery Bypass Grafting

Background

To compare the performance of our institutionally refined microplegia protocol in conjunction with minimal extracorporeal circulation system (MiECC) with off-pump coronary artery bypass grafting (OPCAB).

Methods

We conducted a single center study including patients undergoing isolated CABG surgery performed either off-pump or on-pump using our refined microplegia protocol in conjunction with MiECC. We used propensity modelling to calculate the inverse probability of treatment weights (IPTW). Primary endpoints were peak values of high-sensitivity cardiac troponin T (hs-cTnT) during hospitalization, and respective first values on the first postoperative day. Endpoint analysis was adjusted for intraoperative variables.

Results

After IPTW, we could include 278 patients into our analyses, 153 of which had received OPCAB and 125 of which had received microplegia. Standardized differences indicated that treatment groups were comparable after IPTW. The multivariable quantile regression yielded a nonsignificant median increase of first hs-cTnT by 39 ng/L (95% CI -8 to 87 ng/L, p = 0.11), and of peak hs-cTnT by 35 ng/L (CI -13 to 84, p = 0.11), and of peak hs-cTnT by 35 ng/L (CI -13 to 84, p = 0.11), and of peak hs-cTnT by 35 ng/L (CI -13 to 84, p = 0.11), and of peak hs-cTnT by 35 ng/L (CI -13 to 84.

Conclusion

The use of our institutionally refined microplegia in conjunction with MiECC was associated with similar results with regard to ischemic injury, expressed in hs-cTnT compared to OPCAB. MACCE was seen equally frequent. ICU discharge was earlier if microplegia was used.

Cost-effectiveness of routine transoesophageal echocardiography during cardiac surgery: a discrete-event simulation study

BACKGROUND

The aim of this study was to simulate and compare the healthcare and economic outcomes associated with routine use of intraoperative transoesophageal echocardiography (TOE) in patients undergoing cardiac surgery with those associated with a scenario where TOE is not routinely used.

METHODS

The impact of TOE on surgical decision-making was estimated through a systematic literature review. Individual short-term morbidity and mortality estimates were generated by application of the Society of Thoracic Surgeons risk calculator. Long-term event rates, unit costs, and utility weights were sourced from published literature and expert opinion. A discrete-event simulation model was then constructed to simulate both the in-hospital and post-discharge outcomes for patients undergoing cardiac surgery. Robustness of the base case results was examined through deterministic and probabilistic sensitivity analyses. An incremental cost-effectiveness ratio of €30 000 per quality-adjusted life-year gained was assumed to represent acceptable cost-effectiveness.

RESULTS

Routine use of intraoperative TOE was associated with lower costs and higher benefits per patient, which indicates that use of TOE is a dominant strategy. The intervention resulted in the avoidance of 299 cardiac complications, 20 strokes, and 11 all-cause deaths per 10 000 patients. Routine intraoperative TOE was associated with an increased occurrence of bleeding owing to more valvular surgery and subsequent long-term anticoagulation.

CONCLUSIONS

Routine intraoperative TOE is a cost-effective procedure for patients undergoing cardiac surgery, leading to lower overall costs. It was associated with a decrease in long-term complications including stroke, cardiac complications, and death, although there was a slight increase in extracranial bleeding events.

Long-term survival following on-pump and off-pump coronary artery bypass graft surgery: a propensity score-matched analysis

OBJECTIVES

Recent studies have once again brought into focus the long-term survival following off-pump coronary artery bypass grafting (OPCAB) compared with conventional on-pump coronary artery bypass grafting surgery (ONCAB). The aim of this study was to compare the long-term risk-adjusted survival rates in patients undergoing coronary artery bypass grafting (CABG) using these 2 techniques.

METHODS

We undertook a propensity score-matched analysis of 10 293 patients who underwent CABG at our single institution between 2000 and 2016. A logistic regression model was fitted using 14 covariates and their 2-way interactions to calculate an estimated propensity score [area under curve (AUC) 0.69], from which 1:1 nearest neighbour matching was performed. Patient survival was assessed using the Kaplan-Meier method and log-rank test.

RESULTS

Of the total cohort, 8319 patients had ONCAB and 1974 had OPCAB. Prior to matching, the OPCAB group had marginally higher EuroSCORE [3.7 ± 2.7 vs 3.5 ± 3, median (interquartile range) 3 (2-5) vs 3 (2-5), P = 0.016] and significantly lower average number of grafts per patient (2.39 ± 0.72 vs 2.75 ± 0.48, P < 0.001). Post-matching distributions between OPCAB and ONCAB showed a substantial improvement in balance in preoperative patient characteristics. The 2 surgery groups differed significantly in survival (P < 0.001). OPCAB demonstrated improved long-term survival at 10 years [84.8%, 95% confidence interval (CI) (82.7-86.9%) vs 75.8%, 95% CI (73.4-78.2%)] and 15 years [65.4%, 95% CI (61.4-69.6%) vs 58.5%, 95% CI (54.9-62.3%)]. Results of sensitivity analysis for 1:2 and 1:3 matched data were in concordance with these findings of survival.

CONCLUSION

At our institution, selected patients who underwent OPCAB had lower in-hospital morbidity and improved long-term survival when compared with a matched population of ONCAB patients.

Rivaroxaban, Aspirin, or Both to Prevent Early Coronary Bypass Graft Occlusion: The COMPASS-CABG Study

BACKGROUND

Patients with recent coronary artery bypass graft (CABG) surgery are at risk for early graft failure, which is associated with a risk of myocardial infarction and death. In the COMPASS (Cardiovascular OutcoMes for People Using Anticoagulation StrategieS) trial, rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily compared with aspirin 100 mg once daily reduced the primary major adverse cardiovascular events (MACE) outcome of cardiovascular death, stroke, or myocardial infarction. Rivaroxaban 5 mg twice daily alone did not significantly reduce MACE.

OBJECTIVES

This pre-planned substudy sought to determine whether the COMPASS treatments are more effective than aspirin alone for preventing graft failure and MACE after CABG surgery.

METHODS

The substudy randomized 1,448 COMPASS trial patients 4 to 14 days after CABG surgery to receive the combination of rivaroxaban plus aspirin, rivaroxaban alone, or aspirin alone. The primary outcome was graft failure, diagnosed by computed tomography angiogram 1 year after surgery.

RESULTS

The combination of rivaroxaban and aspirin and the regimen of rivaroxaban alone did not reduce the graft failure rates compared with aspirin alone (combination vs. aspirin: 113 [9.1%] vs. 91 [8.0%] failed grafts; odds ratio [OR]: 1.13; 95% confidence interval [CI]: 0.82 to 1.57; p = 0.45; rivaroxaban alone vs. aspirin: 92 [7.8%] vs. 92 [8.0%] failed grafts; OR: 0.95; 95% CI: 0.67 to 1.33; p = 0.75). Compared with aspirin, the combination was associated with fewer MACE (12 [2.4%] vs. 16 [3.5%]; hazard ratio [HR]: 0.69; 95% CI: 0.33 to 1.47; p = 0.34), whereas rivaroxaban alone was not (16 [3.3%] vs. 16 [3.5%]; HR: 0.99, CI: 0.50 to 1.99; p = 0.98). There was no fatal bleeding or tamponade within 30 days of randomization.

CONCLUSIONS

The combination of rivaroxaban 2.5 mg twice daily plus aspirin or rivaroxaban 5 mg twice daily alone compared with aspirin alone did not reduce graft failure in patients with recent CABG surgery, but the combination of rivaroxaban 2.5 mg twice daily plus aspirin was associated with similar reductions in MACE, as observed in the larger COMPASS trial. (Cardiovascular OutcoMes for People Using Anticoagulation StrategieS [COMPASS]; NCT01776424).

Prevalence and Impact of Treatment Crossover in Cardiac Surgery Randomized Trials: A Meta-Epidemiologic Study

Background Crossover dilutes treatment effect and reduces statistical power of intention-to-treat analysis. We examined incidence and impact on cardiac surgery randomized controlled trial (RCT) outcomes of crossover from experimental to control interventions, or vice versa. Methods and Results MEDLINE, EMBASE, and Cochrane Library were searched, and RCTs (≥100 patients) comparing ≥2 adult cardiac surgical interventions were included. Crossover from the initial treatment assignment and relative risks (RRs) for each trial's primary end point and mortality at longest available follow-up were extracted. All RRs were calculated as >1 favored control group and <1 favored experimental arm. Primary outcome was the effect estimate for primary end point of each RCT, and secondary outcome was all-cause mortality; both were appraised as RR at the longest follow-up available. Sixty articles reporting on 47 RCTs (25 440 patients) were identified. Median crossover rate from experimental to control group was 7.0% (first quartile, 2.0%; third quartile, 9.7%), whereas from control to experimental group, the rate was 1.3% (first quartile, 0%; third quartile, 3.6%). RRs for primary end point and mortality were higher in RCTs with higher crossover rate from experimental to control group (RR, 1.01 [95% CI, 0.94-1.07] versus RR, 0.80 [95% CI, 0.66-0.97] and RR, 1.02 [95% CI, 0.95-1.11] versus RR, 0.94 [95% CI, 0.82-1.07], respectively). Crossover from control to experimental group did not alter effect estimates for primary end point or mortality (RR, 0.82 [95% CI, 0.63-1.05] versus RR, 0.95 [95% CI, 0.86-1.04] and RR, 0.88 [95% CI, 0.73-1.07] versus RR, 1.02 [95% CI, 0.95-1.09], respectively). Conclusions Crossover from experimental to control group is associated with outcomes of cardiac surgery RCTs. Crossover should be minimized at designing stage and carefully appraised after study completion.

Early and long-term outcomes of coronary artery bypass surgery with and without use of heart-lung machine and with special respect to renal function - A retrospective study

The aim of our study was to compare early and long-term outcome of patients undergoing either on-pump or off-pump coronary artery bypass grafting with special focus on impairment of renal function. Five hundred ninety-three consecutive patients undergoing coronary artery bypass grafting were retrospectively analyzed. They were assigned either to on-pump (n = 281) or to off-pump (n = 312) group. Early and long-term outcomes were analyzed with special focus on renal function. Basic demographics and preoperative characteristics did not differ between groups (p>0.05) as well as postoperative renal parameters (p>0.05). Postoperative odds ratios (OR) of off-pump group in comparison to on-pump group were higher without reaching significance in terms of incidence of gastrointestinal complications and pneumonia (OR = 2.23 and 1.61, respectively) as well as hazard ratios (HR) on long-term follow-up for mortality and incidence of myocardial infarction (HR = 1.50 and 2.29, respectively). Kaplan-Meier estimation analysis also revealed similar results for both groups in terms of mid- and long-term survival (Breslow p = 0.062 and Log-Rank p = 0.064, respectively) and for incidence of myocardial infarction (Breslow p = 0.102 and Log-Rank p = 0.103, respectively). Our study suggests that use or not use of coronary artery bypass did not influence postoperative renal function. Odds of early outcomes were similar in both groups as well as incidence of myocardial infarction and mortality in long-term follow-up.

Association of T Cell-Derived Inflammatory Cytokines With Acute Kidney Injury and Mortality After Cardiac Surgery

Introduction

Animal models of renal ischemia-reperfusion injury (IRI) demonstrate that interferon (IFN)-γ producing T-helper (Th)-1 cells worsen acute kidney injury (AKI), whereas interleukin (IL)-4– and IL-13–producing Th2 cells lead to repair. We tested the association of these cytokines with AKI and mortality in patients who underwent cardiac surgery.

Methods

In 1444 participants of a multicenter, prospective, observational cohort, we measured 10 plasma biomarkers before and after cardiac surgery (IFN-γ, IL-4, IL-13, tumor necrosis factor [TNF]-α, IL-1β, IL-2, IL-6, IL-8, IL-10, and IL-12p70) and combined these biomarkers using principal component analysis (PCA). We also tested independent associations of Th1 (IFN-γ) and Th2 (IL-4 and IL-13) biomarkers with clinical outcomes of postoperative AKI and 1-year mortality.

Results

AKI occurred in 492 participants (34%), and 1-year mortality occurred in 81 participants (6%). Within 6 hours after surgery, IFN-γ, IL-4, and IL-13 increased 2.1-, 6.0-, and 4.6-fold, respectively, from their preoperative levels. Patients with higher levels of IFN-γ had higher odds of AKI (adjusted odds ratio per log change, 1.35 [1.13, 1.6]) and mortality (1.51 [1.17, 1.94]). Patients with higher levels of IL-4 and IL-13 also had higher odds of AKI (1.26 [1.09, 1.46] and 1.4 [1.16, 1.69], respectively) and mortality (1.46 [1.18, 1.82] and 1.71 [1.27, 2.31], respectively). Adding biomarkers to the clinical variables through use of PCA improved the area under the curve by 0.01 for AKI and 0.04 for mortality, resulting in final areas under the curve of 0.85 (0.83–0.87) and 0.76 (0.70–0.81), respectively.

Conclusion

Both Th1 and Th2 cytokines increased immediately after cardiac surgery and were associated with AKI and 1-year mortality. Our findings indicate activation of both Th1 and Th2 pathways after cardiac surgery rather than predominance of either pathway.

Off-Pump Versus On-Pump Bypass Surgery for Left Main Coronary Artery Disease

BACKGROUND

Concerns remain for a greater risk of incomplete revascularization and reduced survival with off-pump coronary artery bypass grafting (CABG) surgery compared with on-pump surgery particularly in patients with left main disease and extensive underlying myocardial ischemia.

OBJECTIVES

This study sought to compare outcomes following off-pump versus on-pump surgery for left main disease by performing a post hoc analysis from the multicenter, randomized EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial.

METHODS

The EXCEL trial was designed to compare percutaneous coronary intervention with everolimus-eluting stents versus CABG in patients with left main disease. CABG was performed with or without cardiopulmonary bypass (on-pump vs. off-pump surgery) according to the discretion of the operator. The 3-year outcomes in the off-pump and on-pump groups were compared using inverse probability of treatment weighting (IPTW) for treatment effect estimation.

RESULTS

Among 923 CABG patients, 652 and 271 patients underwent on-pump and off-pump surgery, respectively. Despite a similar extent of disease, off-pump surgery was associated with a lower rate of revascularization of the left circumflex coronary artery (84.1% vs. 90.0%; p = 0.01) and right coronary artery (31.1% vs. 40.6%; p = 0.007). After IPTW adjustment for baseline differences, off-pump surgery was associated with a significantly increased risk of 3-year all-cause death (8.8% vs. 4.5%; hazard ratio: 1.94; 95% confidence interval: 1.10 to 3.41; p = 0.02) and a nonsignificant difference in the risk for the composite endpoint of death, myocardial infarction, or stroke (11.8% vs. 9.2%; hazard ratio: 1.28; 95% confidence interval: 0.82 to 2.00; p = 0.28).

CONCLUSIONS

Among patients with left main disease treated with CABG in the EXCEL trial, off-pump surgery was associated with a lower rate of revascularization of the coronary arteries supplying the inferolateral wall and an increased risk of 3-year all-cause death compared with on-pump surgery.

Revascularization in left ventricular dysfunction: an update

PURPOSE OF REVIEW

The purpose of this article is to provide an overview of revascularization in patients with coronary artery disease (CAD) and left ventricular dysfunction (LVD).

RECENT FINDINGS

Patients with significant CAD and LVD are a high-risk patient population. They make up a minority of the cases from the largest, prospective coronary revascularization trials. The Surgical Treatment for Ischemic Heart Failure (STICH) Trial and its substudies are the most important and well cited in this field. The 10-year data from STICH showed that surgical revascularization was associated with lower all-cause mortality compared with medical therapy. Several smaller studies have confirmed that surgical revascularization carries a significant risk of short-term mortality but overall improved long-term outcomes in patients with LVD. Data from multiple observational studies further confirm that coronary artery bypass graft (CABG) is superior to percutaneous coronary revascularization for long-term survival and freedom from repeat revascularization in patients with LVD. We suggest that patients with LVD undergoing CABG should be considered for multiarterial grafting and that some patients may benefit from an off-pump procedure.

SUMMARY

Surgical revascularization confers a long-term survival benefit in patients with significant CAD and LVD. Further studies will be needed to precisely determine the ideal candidate for surgical versus percutaneous revascularization.

Preoperative intra-aortic balloon pump inserted in acute myocardial infarction patients without cardiogenic shock undergoing surgical coronary revascularization

OBJECTIVES

The benefit of preoperative intra-aortic balloon pump implantation in high-risk cardiac surgery patients is still debated. The role of preoperative intra-aortic balloon pump insertion in acute myocardial infarction patients without cardiogenic shock undergoing off-pump coronary artery bypass grafting remains unknown. This study aimed to determine the efficacy and safety of the preoperative intra-aortic balloon pump insertion in those patients undergoing off-pump coronary artery bypass grafting.

METHODS

A total of 421 consecutive acute myocardial infarction patients without cardiogenic shock who underwent isolated off-pump coronary artery bypass grafting were enrolled in this retrospective observational propensity score-matched analysis study. Patients who received intra-aortic balloon pump before off-pump coronary artery bypass grafting (the intra-aortic balloon pump group, n = 157) were compared with those who had not (control group, n = 264). The 30-day postoperative survival, postoperative complications, and postoperative hospital length of stay were compared between the two groups.

RESULTS

A total of 99 pairs of patients were matched. The preoperative intra-aortic balloon pump did not show a 30-day postoperative survival benefit compared with the control group (hazard ratio, 0.9; 95% confidence interval, 0.2-4.2; p = 0.92). Patients with preoperative intra-aortic balloon pump were more likely to have shorter postoperative lengths of stay (8 (6-11) days vs. 10 (6-15) days, p = 0.02) and decreased total days in the hospital (median days: 18.2 vs. 21.8, p = 0.02) compared to patients without balloon pumps.

CONCLUSION

Preoperative intra-aortic balloon pump insertion in acute myocardial infarction patients without cardiogenic shock undergoing off-pump coronary artery bypass grafting improved convalescence as shown by significantly shorter postoperative lengths of hospital stay.

Five-year costs from a randomised comparison of bilateral and single internal thoracic artery grafts

BACKGROUND

The use of bilateral internal thoracic arteries (BITA) for coronary artery bypass grafting (CABG) may improve survival compared with CABG using single internal thoracic arteries (SITA). We assessed the long-term costs of BITA compared with SITA.

METHODS

Between June 2004 and December 2007, 3102 patients from 28 hospitals in seven countries were randomised to CABG surgery using BITA (n=1548) or SITA (n=1554). Detailed resource use data were collected from the initial hospital episode and annually up to 5 years. The associated costs of this resource use were assessed from a UK perspective with 5 year totals calculated for each trial arm and pre-selected patient subgroups.

RESULTS

Total costs increased by approximately £1000 annually in each arm, with no significant annual difference between trial arms. Cumulative costs per patient at 5-year follow-up remained significantly higher in the BITA group (£18 629) compared with the SITA group (£17 480; mean cost difference £1149, 95% CI £330 to £1968, p=0.006) due to the higher costs of the initial procedure. There were no significant differences between the trial arms in the cost associated with healthcare contacts, medication use or serious adverse events.

CONCLUSIONS

Higher index costs for BITA were still present at 5-year follow-up mainly driven by the higher initial cost with no subsequent difference emerging between 1 year and 5 years of follow-up. The overall cost-effectiveness of the two procedures, to be assessed at the primary endpoint of the 10-year follow-up, will depend on composite differences in costs and quality-adjusted survival.

TRIAL REGISTRATION NUMBER

ISRCTN46552265.

Compliance With Guideline-Directed Medical Therapy in Contemporary Coronary Revascularization Trials

BACKGROUND

Despite the well-established benefits of secondary cardiovascular prevention, the importance of concurrent medical therapy in clinical trials of coronary revascularization is often overlooked.

OBJECTIVES

The goal of this study was to assess compliance with guideline-directed medical therapy (GDMT) in clinical trials and its potential impact on the comparison between percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG).

METHODS

The Cochrane Central Register of Controlled Trials and MEDLINE were searched from 2005 to August 2017. Clinical trial registries and reference lists of relevant studies were also searched. Randomized controlled trials comparing PCI with drug-eluting stents versus CABG and reporting medical therapy after revascularization were included. The study outcome was compliance with GDMT, defined as the following: 1) any antiplatelet agent plus beta-blocker plus statin (GDMT1); and 2) any antiplatelet agent plus beta-blocker plus statin plus angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (GDMT2). Data collection and analysis were performed according to the methodological recommendations of The Cochrane Collaboration.

RESULTS

From a total of 439 references, 5 trials were included based on our inclusion and exclusion criteria. Overall, compliance with GDMT1 was low and decreased over time from 67% at 1 year to 53% at 5 years. Compliance with GDMT2 was even lower and decreased from 40% at 1 year to 38% at 5 years. Compliance with both GDMT1 and GDMT2 was higher in PCI than in CABG at all time points. Meta-regression suggested an association between lower use of GDMT1 and adverse clinical outcomes in PCI versus CABG at 5 years.

CONCLUSIONS

Compliance with GDMT in contemporary clinical trials remains suboptimal and is significantly lower after CABG than after PCI, which may influence the comparison of clinical trial endpoints between those study groups.

Acute kidney injury after cardiac surgery: prevalence, impact and management challenges

Acute kidney injury (AKI) is a major medical problem that is of particular concern after cardiac surgery. Perioperative AKI is independently associated with an increase in short-term morbidity, costs of treatment, and long-term mortality. In this review, we explore the definition of cardiac surgery-associated acute kidney injury (CSA-AKI) and identify diverse mechanisms and risk factors contributing to the renal insult. Current theories of the pathophysiology of CSA-AKI and description of its clinical course will be addressed in this review. Data on the most promising renal protective strategies in cardiac surgery, from well-designed studies, will be scrutinized. Furthermore, diagnostic tools such as novel biomarkers of AKI and their potential utility will be discussed.

Long Term Outcomes of The Off-Pump and On-Pump Coronary Artery Bypass Grafting In A High-Volume Center

Coronary artery bypass grafting (CABG) remains the most frequent surgery in the practice of an adult cardiac surgeon and the most frequently performed cardiac surgical procedure worldwide. Despite the ongoing debates regarding the superiority or inferiority of off-pump coronary artery bypass grafting, it still comprises 15-30% of all CABG cases varying in different national registries. We performed a propensity matched study of 302 consecutive CABG patients,143 off -pump cases performed by the four experienced off-pump surgeons and the on-pump CABG cases performed by those surgeons and four other experienced coronary surgeons. The five year follow up was performed and data collected comprised of mortality, rehospitalization due to cardiac origin, repeated revascularization, myocardial infarction and cerebrovascular accident. Overall, the off-pump group of patients had a higher risk profile than the patients in the on-pump group. After matching, fewer differences were found between the groups. Propensity score matching analysis showed no difference in long-term survival as well as MACCE and repeated revascularization. The higher risk profile of the patients subjected to OPCAB and the comparable survival to lower risk CPB patients in this series indicate that in experienced hands, OPCAB is a valuable option in this important subgroup of patients.

Hybrid coronary revascularization versus off-pump coronary artery bypass grafting and percutaneous coronary intervention for the treatment of two-vessel coronary artery disease with proximal left anterior descending artery stenosis

Background

This study sought to compare clinical outcomes of hybrid coronary revascularization (HCR) with off-pump coronary artery bypass grafting (OPCAB) and percutaneous coronary intervention (PCI) for the treatment of two-vessel coronary artery disease (CAD) including proximal LAD stenosis.

Methods

From January 2009 to December 2016, 52 patients of two-vessel CAD including proximal LAD stenosis underwent HCR at Rui Jin Hospital. Using propensity score methodology, these patients were matched with those in the OPCAB and PCI cohorts. The primary endpoint during follow-up was main adverse cardiovascular and cerebrovascular events (MACCE).

Results

The intensive care unit (ICU) length of stay (LOS) and the hospital LOS were shorter in the HCR group than in the OPCAB group (ICU LOS: P<0.001; hospital LOS: P=0.027). The mean follow-up time was 59 months (interquartile range, 42 to 79 months). The 8-year freedom from MACCE of the HCR group was higher than that of the PCI group (P=0.008), but similar to that of the OPCAB group (P=0.893).

Conclusions

HCR provides favorable outcomes for selected patients with two-vessel CAD including proximal LAD stenosis.

Early and Mid-Term Outcomes of Patients Undergoing Coronary Artery Bypass Grafting in Ischemic Cardiomyopathy

Background Many observational studies and trials have shown that coronary artery bypass grafting improves the survival in patients with ischemic cardiomyopathy. However, these results are based on data generated from developed countries. Poor socioeconomic statuses, lack of uniformity in healthcare delivery, differences in risk profile, and affordability to access optimal health care are some factors that make the conclusions from these studies irrelevant to patients from India. Methods and Results One-hundred and sixty-two patients with severe left ventricular dysfunction (ejection fraction ≤35%) who underwent coronary artery bypass grafting from 2009 to 2017 were enrolled for this study. Mean age of the study population was 58.67±9.70 years. Operative mortality was 11.62%. Thirty day/in-house composite outcome of stroke and perioperative myocardial infarction were 5.8%. The percentage of survival for 1 year was 86.6%, and 5-year survival was 79.9%. Five-year event-free survival was 49.3%. The mean ejection fraction improved from 30.7±4.08% (range 18-35) to 39.9±8.3% (range 24-60). Lack of improvement of left ventricular function was a strong predictor of late mortality (hazard ratio, 21.41; CI 4.33-105.95). Even though there was a trend towards better early outcome in off-pump CABG , the 5-year survival rates were similar in off-pump and on-pump group (73.4% and 78.9%, respectively; P value 0.356). Conclusions We showed that coronary artery bypass grafting in ischemic cardiomyopathy was associated with high early composite outcomes. However, the 5-year survival rates were good. Lack of improvement of left ventricular function was a strong predictor of late mortality.

Current Readings on Outcomes After Off-Pump Coronary Artery Bypass Grafting

Off-pump coronary artery bypass grafting (CABG) gained popularity in the 1990s through early 2000s as surgeons sought to mitigate the purported adverse effects of cardiopulmonary bypass and reduce the risk of neurologic events from aortic manipulation. Since then, results of several large randomized controlled trials and meta-analyses have failed to demonstrate an advantage of off-pump CABG over traditional on-pump CABG and have even raised concerns about potential suboptimal outcomes. The modern debate about off- vs on-pump CABG centers around long-term outcomes, the role of surgeon experience, identification of specific patient populations for which off-pump CABG is most appropriate, and identification of novel techniques and technologies to improve long-term outcomes. We review the key findings of 5 contemporary papers that address these issues and provide a current perspective on the status of off-pump CABG.

Predictors of acute kidney injury in patients undergoing adult cardiac surgery

Background

Acute kidney injury (AKI) after cardiac surgery (CS) is not uncommon and has serious effects on mortality and morbidity. A majority of patients suffer mild forms of AKI. There is a paucity of Indian data regarding this important complication after CS.

Aims and Objectives

The primary objective was to study the incidence of AKI associated with CS in an Indian study population. Secondary objectives were to describe the risk factors associated with AKI-CS in our population and to generate outcome data in patients who suffer this complication.

Methods

Serial patients (n = 400) presenting for adult CS (emergency/elective) at a tertiary referral care hospital in South India from August 2016 to November 2017 were included as the study individuals. The incidence of AKI-CS AKI network (AKIN criteria), risk factors associated with this condition and the outcomes following AKI-CS are described.

Results

Out of 400, 37 (9.25%) patients developed AKI after CS. AKI associated with CS was associated with a mortality of 13.5% (no AKI group mortality 2.8%, P = 0.001 [P < 0.05]). When AKI was severe enough to need renal replacement therapy, the mortality increased to 75%. Patients with AKI had a mean hospital stay 16.92 ± 12.75 days which was comparatively longer than patients without AKI (14 ± 7.98 days). Recent acute coronary syndrome, postoperative atrial fibrillation, and systemic hypertension significantly predicted the onset of AKI-CS in our population.

Conclusions

The overall incidence of AKI-CS was 9.25%. The incidence of AKI-CS requiring dialysis (Stage 3 AKIN) AKI-CS was lower (2%). However, mortality risks were disproportionately high in patients with AKIN Stage 3 AKI-CS (75%). There is a need for quality improvement in the care of patients with AKI-CS in its most severe forms since mortality risks posed by the development of Stage 3 AKIN AKI is higher than reported in other index populations from high resource settings.

Minimally Invasive coronary surgery compared to STernotomy coronary artery bypass grafting: The MIST trial

RATIONALE

Minimally invasive cardiac surgery has emerged as a safe alternative to standard cardiac surgery. Minimally invasive coronary surgery (MICS CABG) was developed to allow adequate exposure and complete revascularization in CABG from a small thoracotomy incision without cardiopulmonary bypass. Multiple studies have reported significant shorter length of hospital stay and earlier postoperative physical recovery for MICS CABG patients when compared to sternotomy CABG patients. However, there have been no convincing clinical trials that demonstrate improvement in post-operative quality of life for patients who undergo MICS CABG.

STUDY DESIGN

The Minimally Invasive Coronary Surgery compared to Sternotomy Coronary Artery Bypass Grafting (MIST) trial is a multi-centered, prospective randomized controlled trial that compares the quality of life and recovery in the early post-operative period between patients undergoing MICS CABG versus patients undergoing sternotomy CABG. Patients will be randomized either to the MICS CABG group or the sternotomy CABG group, and the target enrollment is 88 patients per group. The primary outcome is quality of life assessment performed by SF-36 questionnaire at 1 month.

CONCLUSION

The MIST trial is the first prospective study that compares the quality of life between MICS CABG and sternotomy CABG patients. The results of this trial may enhance the procedural desirability of MICS CABG by patients and provide an incentive for surgeons and institutions to increase the availability of MICS CABG in suitable patients.

Off-Pump Coronary Artery Bypass Grafting in Acute Coronary Syndrome: Focus on Safety and Completeness of Revascularization

Background Emergency coronary artery bypass grafting (CABG) in the setting of acute coronary syndrome (ACS) has been associated with increased morbidity and mortality. Avoiding cardiopulmonary bypass might be advantageous, but the role of off-pump CABG (OPCAB) remains controversial, as it has been associated with incomplete revascularization in several studies. The objective of this study was to evaluate the feasibility, efficacy, and outcome of OPCAB surgery in ACS patients.

Methods We performed a retrospective review of ACS patients who underwent on-pump CABG (ONCAB) or OPCAB, either emergently or delayed, at our institution.

Results Between January 2015 and December 2016, a total of 205 consecutive ACS patients underwent either ONCAB (109 patients, 53.2%) or OPCAB surgery (96 patients, 46.8%). EuroSCORE II levels (5.6 ± 7.2 vs 4.9 ± 6.5, p = 0.226) and demography were comparable between groups.

A trend towards lower postoperative mortality was observed in OPCAB patients (2.1 vs 5.5%). The incidence of postoperative stroke and low cardiac output syndrome, as well as the duration of inotropic support and the need for re-sternotomy, was significantly lower in the OPCAB group (p < 0.05).

CABG performed instantly in an emergency situation was not associated with increased mortality or morbidity when compared with delayed procedures, and OPCAB surgery in emergency patients was associated with lower postoperative morbidity and shorter stays in the intensive care unit (p < 0.05).

There were no differences in completeness of revascularization between groups (median 1 [1–1.33;0.33–1.67] OPCAB versus median 1 (1–1.33;0.67–2) ONCAB, p = 0.617), even in the emergency setting.

Conclusion OPCAB surgery is safe and effective in ACS and may be considered in hemodynamically stable patients in the emergency setting.

Off- vs. On-Pump Coronary Artery Bypass Grafting Long-Term Survival is Driven by Incompleteness of Revascularisation

BACKGROUND

Off-pump coronary artery bypass grafting (CABG) negates the requirement for extracorporeal circulation used with the traditional on-pump approach. However, off-pump CABG is technically more challenging and may theoretically lead to less complete revascularisation. Recent data suggests a prognostic benefit for traditional on-pump CABG, but the mechanism for this remains unclear. We hypothesised that the inferior outcomes with off-pump CABG could be driven by the need for repeat revascularisation, with this benefit only becoming clear at long-term follow-up. We therefore evaluated short, medium and long-term outcomes of patients undergoing revascularisation with on vs. off-pump CABG.

METHODS

Electronic databases were searched to identify suitable randomised controlled trials enrolling ≥100 patients in each arm. Clinical outcomes were extracted at 30-days, 12-months or >4years. The primary outcome was long-term all-cause death, while secondary outcomes included 30-day, 12-month and >4-year cardiac death, stroke, myocardial infarction or revascularisation.

RESULTS

Thirteen (13) studies comprising 13,234 patients were included. Off-pump CABG was associated with an increased risk of all-cause death (Odds Ratio [OR] 1.18, 95% confidence interval [CI] 1.02-1.32, p=0.01) and repeat bypass surgery (OR 2.57, 95%CI 1.23-5.39, p=0.01) at long-term follow-up. A significant, increased requirement for revascularisation in off-pump was seen at 12-month follow-up (OR 1.59, 95%CI 1.09-2.33, p=0.02). No differences were noted between groups at 30-days, 12-months and >4years for myocardial infarction or stroke.

CONCLUSIONS

Off-pump CABG is associated with significantly higher rates of all-cause mortality rate at long-term follow-up. These outcomes demonstrate a temporal relationship that may be driven by a greater requirement for repeat revascularisation at 1- and 5-year follow-up.

STUDY REGISTRATION

CRD42018102019 (PROSPERO).

Coronary Artery Bypass in Young Patients-On or Off-Pump?

A definitive conclusion regarding whether on-pump or off-pump coronary artery bypass is preferable in young patients is lacking. The aim of our study was to perform a long-term comparison of the two approaches in young patients. We analyzed the National Health Insurance Research Database, using data for patients between 18 and 45 years of age who had undergone isolated coronary artery bypass between 2001 and 2011. The study endpoints were: all-cause death, major adverse cardiac and cerebrovascular events, and repeat revascularization within 30 days, 1 year, 5 years, and the entire 10-year follow-up period. A total of 344 patients received off-pump surgery and 741 patients received on-pump surgery. Preoperative characteristics and comorbidities were similar in both groups, and all-cause mortality was almost equal (p = 0.716). The 5-year survival rates were 93.9% and 92.2% in the off-pump and on-pump groups, respectively, and the 10-year survival rates were 86.3% and 82.1%, respectively. The repeat revascularization rate was significantly lower in the on-pump group (p = 0.0407). Both the on-pump and off-pump methods offer equally good long-term outcomes in terms of mortality and major adverse cardiac and cerebrovascular events. However, the need for repeat revascularization is a concern in the long term after off-pump surgery.

Behavior of Ultrasensitive C-Reactive Protein in Myocardial Revascularization with and without Cardiopulmonary Bypass

Objective

To analyze the inflammation resulting from myocardial revascularization techniques with and without cardiopulmonary bypass, based on ultrasensitive C-reactive protein (US-CRP) behavior.

Methods

A prospective non-randomized clinical study with 136 patients was performed. Sixty-nine patients were enrolled for Group 1 (on-pump coronary artery bypass - ONCAB) and 67 patients were assigned to Group 2 (off-pump coronary artery bypass - OPCAB). All study participants had blood samples collected for analysis of glucose, triglycerides, creatinine, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and creatinephosphokinase (CPK) in the preoperative period. The samples of creatinephosphokinase MB (CKMB), troponin I (TnI) and US-CRP were collected in the preoperative period and at 6, 12, 24, 36, 48 and 72 hours after surgery. We also analyzed the preoperative biological variables of each patient (age, smoking, diabetes mellitus, left coronary trunk lesion, body mass index, previous myocardial infarction, myocardial fibrosis). All angiographically documented patients with >70% proximal multiarterial stenosis and ischemia, documented by stress test or classification of stable angina (class II or III), according to the Canadian Cardiovascular Society, were included. Reoperations, combined surgeries, recent acute myocardial infarction, recent inflammatory disease, deep venous thrombosis or recent pulmonary thromboembolism, acute kidney injury or chronic kidney injury were not included.

Results

Correlation values between the US-CRP curve and the ONCAB group, the treatment effect and the analyzed biological variables did not present expressive results. Laboratory variables were evaluated and did not correlate with the applied treatment (P>0.05).

Conclusion

The changes in the US-CRP at each moment evaluated from the postoperative period did not show any significance in relation to the surgical technique applied.

On-Pump Beating/Non-Beating CABG in Stable Angina Have Similar Outcomes

Objective

On pump beating/non-beating coronary artery bypass grafts (CABG) has been compared in patients with unstable angina and/or severe left ventricular dysfunction. There is scarce evidence regarding the beneficial use of on-pump beating CABG in patients with stable angina and normal left ventricular function. Our aim was to study the postoperative results using both techniques in this group of patients.

Methods

One thousand one hundred and forty-five patients with stable angina underwent on-pump isolated CABG in Uruguay from 2011 to 2015. Patients were grouped into beating/non-beating CABG. Operative mortality and long-term survival were evaluated as primary outcome. Logistic regression analysis was performed to define the predictive role of aortic cross clamp (AXC) on prolonged inotropic support, ventilator support and intraoperative glycemia.

Results

Among the included patients, 988 underwent aortic cross clamp. No differences were found in operative mortality, stroke and long-term survival among both groups. Patients without AXC showed higher intraoperative values of glycemia and higher incidence of postoperative prolonged mechanical ventilator support (7.6% vs. 2.4%; P=0.001). The need for prolonged inotropic support was lower in this group of patients (27.4% vs. 49.5%; P<0.001).

Conclusion

On-pump beating CABG has similar operative mortality and long-term survival compared with conventional AXC. Higher intraoperative glycemia and higher incidence for prolonged mechanical ventilator is associated with on-pump beating CABG. On the contrary, higher incidence for prolonged inotropic support is associated with AXC. Taking these factors into consideration, both techniques are safe and allow the surgeon to choose the most comfortable option.

On-Pump Coronary Artery Bypass Graft: The State of the Art

BACKGROUND

Coronary artery bypass grafting (CABG) remains the standard of care for patients with coronary artery disease (CAD). Debate exists concerning several factors, which include percutaneous coronary intervention (PCI) vs. CABG, single vs. bilateral mammary artery grafts, radial artery vs. saphenous vein grafts, right internal mammary artery vs. radial artery grafts, endoscopic vs. open vein-graft harvesting, and on-pump vs. off- pump surgery. Moreover, challenging is the management of diabetic patients with CAD undergoing CABG. This review reports current indications, practice patterns, and outcomes of CABG.

METHODS

Randomized controlled trials comparing CABG to other therapeutical strategies for CAD were searched through MEDLINE, EMBASE, Cochrane databases, and proceedings of international meetings.

RESULTS

Large multicenter randomized and observational studies (SYNTAX, BEST, PRECOMBAT, ASCERT) have reported excellent outcomes in CABG patients, with always fewer rates of operative mortality and major morbidity, than PCI. The 10-year follow-up of ARTS II trial showed no difference between single and bilateral mammary artery. BARI 2D, MASS II, CARDia, FREEDOM trials showed that CABG is the best choice for diabetic patients.

CONCLUSION

CABG still represents one of the most widespread major surgeries, with well-known benefits on symptoms and prognosis in patients with CAD. However, further studies and follow-up data are needed to validate these evidences.