Early outcomes in patients undergoing off-pump coronary artery bypass grafting

Off-Pump Coronary Artery Bypass Grafting is Overutilized

Off-pump coronary artery bypass grafting (CABG), developed to avoid the potential complications of cardiopulmonary bypass, remains a subject of debate. Studies have demonstrated that off-pump CABG is associated with higher rates of incomplete revascularization, inferior graft patency, and increased reintervention rates compared to on-pump CABG, leading to worse outcomes. The theoretical neuroprotective and renal-protective benefits associated with off-pump CABG have not been definitively proven, with stroke and renal failure rates similar to those of on-pump CABG in both short- and long-term follow-up. Off-pump CABG presents technical challenges, contributing to a steep learning curve, and its effectiveness is dependent on surgeon and center experience. Lower-volume centers and surgeons performing off-pump CABG have shown increased rates of mortality and reintervention. Despite the potential cost savings by avoiding cardiopulmonary bypass, the need for repeat interventions and associated complications can lead to higher long-term healthcare costs. This paper advocates for a more selective use of off-pump CABG while maintaining on-pump CABG as the standard approach for patients with coronary artery disease.

Early and midterm outcomes after off pump coronary artery bypass surgery

Purpose

There has been debate whether off pump coronary artery bypass surgery (OPCAB) has results comparable to conventional on pump bypass surgery. This has led to the low uptake of OPCAB in the West. In India, OPCAB is the default mode of coronary revascularization. However, there is scarce data on mid-term outcomes of OPCAB in our patients. This study aims to evaluate both short and mid-term mortality and analyze factors associated with mortality.

Methods

This is a single center study of all consecutive patients undergoing isolated OPCAB from October 2014 to December 2019. Patient data was collected from hospital records and follow-up was from the hospital electronic medical records and telephone interviews. Mortality and factors contributing to survival were analyzed.

Results

Operative mortality was 2.3%. Mid-term mortality was 5.5%. Preoperative renal dysfunction, post-operative renal failure, use of the intra-aortic balloon pump (IABP), re-exploration for bleeding, postoperative stroke, ventilation > 24 h, and postoperative atrial fibrillation were associated with operative mortality. Factors associated with mid-term mortality were age > 62 years, postoperative renal failure, IABP usage, ventilation time > 24 h, and postoperative atrial fibrillation. The mean survival time was 2343.55 + / - 15.27 days and 6-year survival was 88.7%.

Conclusion

OPCAB can safely be performed with satisfactory short and mid-term outcomes. Further corroborative studies from different regions of the country or a multi-center study will help to establish the suitability of the technique in Indian patients.

The Significance of Simple Inflammatory Markers in Off Pump Surgery-Review

The inflammatory background of coronary artery disease is gaining more attention in recent times. Off pump surgery is minimally invasive type of surgical revascularization with relatively low number of applications in cardiac surgery centers worldwide that allows for perioperative inflammatory reactions minimalization. The simple inflammatory markers (neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), platelets to lymphocyte ratio (PLR), systemic inflammatory index (SII), systemic inflammatory response index (SIRI), aggregate index of systemic inflammation (AISI)) possess a clinically significant impact on patients' prognosis and may help to improve patients' long-term results. The review presents the current knowledge regarding their utility in clinical practice. Assessment of inflammatory indices obtained from whole blood count analysis allows to indicate those patients who need scrupulous follow-up due to predicted worse long-term survival. Perioperative measurement and analysis of simple whole blood counts is inexpensive and easily available and may improve the results of surgical revascularization by better identification of patients at higher risk of worse outcomes.

Clinical outcomes of off-pump coronary artery bypass graft in patients with diabetes and non-diabetics: A systematic review and meta-analysis

BACKGROUND AND AIM

Diabetes mellitus is a prevalent risk factor for developing coronary artery disease which worsens the clinical outcomes of patients undergoing coronary artery bypass grafting (CABG). This study aimed to determine the clinical outcomes of patients with diabetes and non-diabetic patients who underwent off-pump CABG surgery.

METHOD

Medline, Scopus, Proquest, Embase, Web of Science, and Google scholar were searched until September 10, 2021. The effect sizes including unstandardized mean difference and odds ratio with 95% confidence interval were calculated using "Metan" package. The Cochran's Q-test and I² statistic were used to assess heterogeneity, a random-effects model was applied to estimate the pooled effect sizes, and meta-regression was used to investigate the factors affecting heterogeneity between studies.

RESULTS

10 studies with 6200 sample sizes were included in the study. In groups with diabetes, Summary odds ratio (SOR) and 95% confidence interval of infection was 2.18 more than non-diabetic groups. Also, odds renal complication was 1.74 more than non-diabetic groups, and the odds cardiovascular complication in groups with diabetes was 1.30 more than non-diabetics. There were no differences in mortality, neurologic, respiratory and surgical complications between groups with diabetes and non-diabetics. Based on meta-regression results, age (Coefficient: 0.942; p = 0.009) had a significant direct relationship and sample size (Coefficient: 0.001; p = 0.009) had an indirect significant relationship with heterogeneity of neurologic outcomes. There was no significant publication bias in our results.

CONCLUSION

Our study revealed that off-pump CABG led to some significant outcomes in patients with diabetes compared to non-diabetics. Renal and infection complications were higher in patients with diabetes but no significant differences were seen in most of other postoperative outcomes between the two groups.

Incidence, predictors, and outcome for post-operative atrial fibrillation in Indian patients undergoing off-pump coronary artery bypass grafting-a prospective observational study

Purpose

Indian patients who undergo surgical revascularization are relatively younger than their Western counterparts and are predominantly revascularized using off-pump coronary artery bypass grafting (OPCAB) technique. They may therefore be at a reduced risk of developing post-operative atrial fibrillation (POAF). The aim of this study was to assess the incidence of POAF, measure its impact on outcomes, and identify the predictors for POAF in the Indian patients undergoing OPCAB. Besides, the ability of European System for Cardiac Operative Risk Evaluation (EuroSCORE) and Society of Thoracic Surgeons (STS) scores in predicting POAF was also assessed.

Methods

In this prospective observational study, all patients undergoing isolated OPCAB in a single institution over a 12-month period were included. Patients undergoing re-operative surgery, emergency procedure, concomitant surgery, or those with history of previously diagnosed or treated atrial fibrillation were excluded. Logistic regression was performed to identify the predictors of POAF. The receiver operating characteristic (ROC) curve was used to determine the ability of EuroSCORE and STS scores to assess risk of developing POAF.

Results

We recruited 1108 patients in the study of which 88 (7.94%) patients developed POAF. Age (OR = 1.082, p < 0.001, 95%CI: 1.050-1.114), unstable angina (OR = 16.32, p = 0.036, 95%CI: 1.2-221.4), presence of diabetes mellitus (OR 1.781, p = 0.025, 95%CI: 1.074-2.955), left atrial size (OR 2.506, p = 0.001, 95%CI: 1.478-4.251), and presence of chronic renal failure (OR 8.7, p = 0.001, 95%CI: 2.4-31.53) were significant predictors of POAF. Both the EuroSCORE (p = 0.035) and the STS score (p = 0.001) were significantly higher in patients developing POAF. The area under the ROC curve for the EuroSCORE II was 0.62 and for the STS score was 0.64 suggesting satisfactory and similar discriminatory power of both the scores to predict POAF in these patients. POAF was associated with significantly increased adverse outcomes like stroke and prolonged hospital stay.

Conclusions

In our study, the incidence of POAF was much lower (7.94%) than that reported previously. POAF significantly increased adverse outcomes and length of hospital stay. Both EuroSCORE II and STS scores had similar discriminating power in predicting POAF.

Bleeding complications after dual antiplatelet therapy with ticagrelor versus dual antiplatelet therapy with clopidogrel-a propensity-matched comparative study of two antiplatelet regimes in off-pump coronary artery bypass grafting

Purpose

Ticagrelor combined with aspirin had shown better saphenous vein graft patency than aspirin with clopidogrel after off-pump coronary artery bypass grafting. However, the safety of this drug in regard to bleeding complications remains unknown. The aim of our study was to assess the bleeding complications of dual antiplatelet therapy with aspirin and ticagrelor compared with aspirin and clopidogrel within the first 3 months after off-pump surgery.

Methods

Three hundred eighty-two consecutive patients who were prescribed aspirin with ticagrelor (ticagrelor group) were compared with 660 patients who received aspirin and clopidogrel (clopidogrel group). After propensity matching, 144 patients in each group were compared for bleeding events and major adverse cardiac and cerebral events. Major bleeding was defined as composite outcome of re-exploration for bleeding, any fatal bleeding, intracranial bleeding, and any bleeding requiring hospitalization.

Results

Patients in the ticagrelor group had more incidence of re-exploration for bleeding (p = 0.042), pericardial effusion requiring drainage (p = 0.007), readmissions (p < 0.01), gastrointestinal bleeding (p = 0.01), and major bleeding (5.8% vs. 2.1%, p < 0.01, OR 2.8 (1.43-5.58)). After propensity analysis, gastrointestinal bleed (p = 0.024), major bleeding (7.6% vs.1.4%, p < 0.001, OR 5.8 (1.28-26.97)), length of ICU stay (p = 0.039), and readmissions (p = 0.003, OR 11.83 (1.51-92.86)) were more in the ticagrelor group. Major adverse cardiac and cerebral events were similar between the groups.

Conclusion

Dual antiplatelet therapy with aspirin and ticagrelor increased gastrointestinal bleeding events, major bleeding events, and readmission rates compared with aspirin and clopidogrel after off-pump coronary artery bypass grafting.

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.