Coronary revascularization with or without cardiopulmonary bypass in patients with preoperative nondialysis-dependent renal insufficiency

Outcomes of off-pump coronary artery bypass grafting in non-dialysis-dependent patients with stage 2 and stage 3 chronic kidney disease

Purpose

To assess the short-term outcomes in non-dialysis-dependent patients with stage 2 and stage 3 chronic kidney disease (CKD), undergoing off-pump coronary artery bypass (OPCAB). To examine whether there was a difference in mortality between stage 2 and stage 3 CKD patients and whether mortality in diabetics was different compared to non-diabetics. Outcomes would be judged on the basis of possible cardiovascular, pulmonary, infective, neurological and renal complications, duration of stay at the intensive therapy unit (ITU), and overall duration of stay at the hospital. A comparative study of outcomes between stage 2 and stage 3 CKD would be undertaken. Also, given the impact of diabetes mellitus in this patient population, a comparative study of outcomes would be made between diabetics and non-diabetics.

Methods

Three hundred fifteen consecutive patients undergoing OPCAB were included in this observational prospective study. Of them, 201 (64%) had stage 3 CKD and 114 (36%) had stage 2 CKD. Nearly half of the study group (49.52%) were diabetics. Data was collected from patients' files, patient observation charts at the ITU, and patient interviews. Continuous variables were expressed as mean ± standard deviation or median (Q1, Q3) as appropriate and qualitative variables presented with the frequency and corresponding percentage. Comparison between diabetic and non-diabetic patients was performed by the Student's t test or chi-square test as appropriate. And when assumptions of parametric test failed, then an appropriate non-parametric test was performed. Repeated measures ANOVA (analysis of variance) was used to see the trend of estimated glomerular filtration rate (eGFR) values. Statistical analysis was done by using SPSS version 19.0 (SPSS Inc., Chicago, IL, USA). All p values <0.05 were considered statistically significant.

Results

The eGFR was measured pre-operatively, on the day following OPCAB and at the time of discharge and the mean eGFR, remained more or less the same throughout (mean of 55.86 ml/min/1.73 m² pre-operatively, 58.39 ml/min/1.73 m² on the day following OPCAB and 58.39 ml/min/1.73 m² at discharge). One patient with stage 2 CKD (0.9%) required hemodialysis post-operatively while 3 patients (1.5%) required the same in the stage 3 CKD group, which was not statistically significant. Nineteen patients (6.03%) required re-intubation for hypoxia in the post-operative period. Post-operative myocardial infarction developed in 12 patients (3.81%). Twenty patients (6.35%) patients needed an intra-aortic balloon pump (IABP) insertion in the peri-operative period owing to hemodynamic compromise. Fifteen patients (4.76%) were re-explored for bleeding following surgery and fifteen patients (4.76%) had a deep sternal wound infection in the post-operative period. New-onset atrial fibrillation was found to be present in 42 stage 3 CKD patients (11%) while it occurred in 21 stage 2 CKD patients (9.6%) (p value = 0.014), which was statistically significant. The mean duration of ITU stay was 84 ± 6.22 h in the stage 2 CKD group and 92.9 ± 8.18 h in the stage 3 CKD group (p value = 0.01), which was statistically significant. Mean duration of ITU stay was 94 ± 10.12 h in the diabetic group while it was 86.7 ± 11.08 h in the non-diabetic group (p value = 0.008) which was statistically significant. Duration of post-operative hospital stay was a mean of 8 ±0.08 days in the diabetic group whereas it was 7 ± 0.04 days in the non-diabetic group (p value = 0.012), which was statistically significant. Surgical mortality was 6 out of 315 patients (1.9%).

Conclusion

OPCAB is a safe and effective revascularization strategy in patients with stage 2 and stage 3 CKD. Short-term outcomes of OPCAB have been good in the patient population in this study, in terms of both surgical morbidity and mortality. Surgical mortality was 1.9%. New-onset atrial fibrillation was found in eleven patients (9.6%) in the stage 2 CKD group and 42 patients (21%) in the stage 3 CKD group (p value =0.014) which was statistically significant. The results of this study reflect the reno-protective nature of OPCAB. The duration of ITU stay and the post-operative duration of stay at the hospital were found to be significantly more in diabetics than in non-diabetics.

Use of Impella CP Device in Off-Pump Coronary Artery Bypass Graft Surgery

Off-pump coronary artery bypass grafting (OPCABG) may be performed on patients with high surgical risk who are poor candidates for traditional mechanical circulatory support. Hemodynamic support with micro-axial mechanical circulatory devices has been performed with limited but promising results.We report a case of a 66-year-old male with multiple comorbidities and low cardiac output undergoing OPCABG. Impella CP device was deployed for "in-pump" support during surgical coronary revascularization resulting in intraoperative stability and uncomplicated post-operative recovery.Previous reports have described the use of the Impella Recover LP 5.0 device for use during OPCABG. We describe the successful and safe perioperative use of the Impella CP device. Despite lower flow rates, adequate support was achieved and the transfemoral cannulation and smaller outer diameter than the Impella 5.0 device may decrease the risk of complications and expedite recovery. Further research will be necessary to determine the optimal perioperative hemodynamic support strategy to offer hemodynamically unstable, high, and prohibitive risk patients.

Off-Pump versus Conventional Coronary Artery Bypass Grafting: A Meta-Analysis and Consensus Statement from the 2004 ISMICS Consensus Conference

Background

The purpose of this evidence-based consensus statement is to systematically review and meta-analyze the randomized and nonrandomized evidence comparing off-pump (OPCAB) to conventional coronary artery bypass (CCAB) surgery and to provide consensus on the role of OPCAB in low- and high-risk surgical patients.

Methods and Results

This consensus conference was conducted according to the American College of Cardiology (ACC)/American Heart Association (AHA) standards for development of clinical practice guidelines. The Steering Committee collated all published studies of OPCAB versus CCAB through May 2004 and developed six questions central to controversies surrounding OPCAB surgery in mortality, morbidity, and resource utilization. For mixed-risk patient populations, meta-analysis of 37 randomized clinical trials (3,369 patients, Level A) reported across a total of 53 papers, and two meta-analyses of nonrandomized trials (Level B) comparing OPCAB versus CCAB were identified. For high-risk patient populations, we performed a meta-analysis of 3 randomized and 42 nonrandomized trials (26,349 patients, Level B).

Conclusion

Meta-analysis of Level A and B evidence provided the basis for the following consensus statements in patients undergoing surgical myocardial revascularization: (1) OPCAB should be considered a safe alternative to CCAB with respect to risk of mortality [Class I, Level A]; (2) With appropriate use of modern stabilizers, heart positioning devices, and adequate surgeon experience, similar completeness of revascularization and graft patency can be achieved [Class IIa, Level A]; (3) OPCAB is recommended to reduce perioperative morbidity [Class I, Level A]; (4) OPCAB may be recommended to minimize midterm cognitive dysfunction [Class IIa, Level A]; (5) OPCAB should be considered as an equivalent alternative to CCAB in regard to quality of life [Class I, Level A]; (6) OPCAB is recommended to reduce the duration of ventilation, ICU and hospital stay, and resource utilization [Class I, Level A]; (7) OPCAB should be considered in high-risk patients to reduce perioperative mortality, morbidity, and resource utilization [Class IIa, Level B].

Off-pump versus on-pump complete coronary artery bypass grafting: Comparison of the effects on the renal damage in patients with renal dysfunction

BACKGROUND

We aimed to compare off-pump technique with on-pump technique on renal function in patients with nondialysis-dependent renal dysfunction who underwent coronary artery bypass grafting.

METHODS

The 94 patients with renal dysfunction undergoing isolated coronary artery bypass grafting were retrospectively analyzed. No patient was receiving dialysis. Patients were randomly assigned to conventional revascularization with cardiopulmonary bypass and beating heart. Both groups were compared in terms of renal dysfunction parameters and dialysis requirement. The logistic regression models were constructed to identify risk factors associated with dialysis requirement.

RESULTS

Renal dysfunction requiring dialysis developed in 9 patients in the on-pump group. The measures analysis of variance was performed on the data that showed worsening of renal function in the on-pump group compared with the off-pump group. Cardiopulmonary bypass is significant as independent predictor for the development of postoperative dialysis.

CONCLUSION

These results suggest that off-pump coronary revascularization offers a superior renal protection and has a significantly lower risk for renal complications in patients with nondialysis-dependent renal dysfunction when compared with conventional coronary revascularization with cardiopulmonary bypass.

Off Pump Coronary Artery Bypass Graft Surgery Versus Conventional Coronary Artery Bypass Graft Surgery: A Systematic Review of the Literature

The recent development of off-pump coronary artery bypass (OPCAB) graft surgical techniques has led to numerous observational and several randomized trials that have investigated outcomes compared with the current gold standard of conventional on-pump coronary bypass (CCAB) graft surgery. This systematic review assesses the current randomized trials that compare OPCAB and CCAB. Numerous end points were investigated, including mortality, stroke, myocardial infarction, atrial fibrillation, blood transfusions, wound infections, and renal failure. In addition to these important outcomes, resource utilization markers were also examined such as hospital length of stay, intensive care unit length of stay, and duration of intubation/ventilation. Finally, when level I evidence from randomized trials was unavailable, level II evidence was examined. This was done for subgroup analysis, where currently no randomized trials exist, looking at OPCAB in high-risk patients. Recommendations were made as to who should receive OPCAB and the potential benefits in this patient population.

Postoperative acute kidney injury defined by RIFLE criteria predicts early health outcome and long-term survival in patients undergoing redo coronary artery bypass graft surgery

Objective

To investigate the impact of postoperative acute kidney injury (AKI) on early health outcome and on long-term survival in patients undergoing redo coronary artery bypass grafting (CABG).

Methods

We performed a Cox analysis with 398 consecutive patients undergoing redo CABG over a median follow-up of 7 years (interquartile range, 4-12.2 years). Renal function was assessed using baseline and peak postoperative levels of serum creatinine. AKI was defined according to the risk, injury, failure, loss, and end-stage (RIFLE) criteria. Health outcome measures included the rate of in-hospital AKI and all-cause 30-day and long-term mortality, using data from the United Kingdom's Office of National Statistics. Propensity score matching, as well as logistic regression analyses, were used. The impact of postoperative AKI at different time points was related to survival.

Results

In patients with redo CABG, the occurrence of postoperative AKI was associated with in-hospital mortality (odds ratio [OR], 3.74; 95% confidence interval [CI], −1.3 to 10.5; P < .01], high Euroscore (OR, 1.27; 95% CI, 1.07-1.52; P < .01), use of IABP (OR, 6.9; 95% CI, 2.24-20.3; P < .01), and reduced long-term survival (hazard ratio [HR], 2.42; 95% CI, 1.63-3.6; P = .01). Overall survival at 5 and 10 years was lower in AKI patients with AKI compared with those without AKI (64% vs 85% at 5 years; 51% vs 68% at 10 years). On 1:1 propensity score matching analysis, postoperative AKI was independently associated with reduced long term survival (HR, 2.8; 95% CI, 1.15-6.7).

Conclusions

In patients undergoing redo CABG, the occurrence of postoperative AKI is associated with increased 30-day mortality and major complications and with reduced long-term survival.

Serum creatinine role in predicting outcome after cardiac surgery beyond acute kidney injury

Serum creatinine is still the most important determinant in the assessment of perioperative renal function and in the prediction of adverse outcome in cardiac surgery. Many biomarkers have been studied to date; still, there is no surrogate for serum creatinine measurement in clinical practice because it is feasible and inexpensive. High levels of serum creatinine and its equivalents have been the most important preoperative risk factor for postoperative renal injury. Moreover, creatinine is the mainstay in predicting risk models and risk factor reduction has enhanced its importance in outcome prediction. The future perspective is the development of new definitions and novel tools for the early diagnosis of acute kidney injury largely based on serum creatinine and a panel of novel biomarkers.

Current options for treatment of chronic coronary artery disease

The primary issues must be discussed regarding the decision making of treating a patient with chronic coronary artery disease (CAD), are the appropriateness of revascularization and the method which will be applied. The criteria will be the symptoms, the evidence of ischemia and the anatomical complexity of the coronary bed. Main indications are persistence of symptoms, despite oral medical treatment and the prognosis of any intervention. The prognosis is based on left ventricular function, on the number of coronary arteries with significant stenosis and the ischemic burden. For patients with symptoms and no evidence of ischemia, there is no benefit from revascularization. If ischemia is proven, revascularization is beneficial. If revascularization is decided, the next important issue must be taken under consideration is the choice of the appropriate method to be applied, surgical or interventional approach. Current treatment options will be presented.

Comparison of diagnostic criteria for acute kidney injury in cardiac surgery

Background

There is considerable controversy regarding the diagnosis of Acute Kidney Injury (AKI), and there are over 30 different definitions.

Objective

To evaluate the incidence and risk factors for the development of AKI following cardiac surgery according to the RIFLE, AKIN and KDIGO criteria, and compare the prognostic power of these criteria.

Methods

Cross-sectional study that included 321 consecutive patients (median age 62 [53-71] years; 140 men) undergoing cardiac surgery between June 2011 and January 2012. The patients were followed for up to 30 days, for a composite outcome (mortality, need for dialysis and extended hospitalization).

Results

The incidence of AKI ranged from 15% - 51%, accordingly to the diagnostic criterion adopted. While age was associated with risk of AKI in the three criteria, there were variations in the remaining risk factors. During follow-up, 89 patients developed the outcome and all criteria were associated with increased risk in the univariate Cox analysis and after adjustment for age, gender, diabetes, and type of surgery. However, after further adjustment for extracorporeal circulation and the presence of low cardiac output, only AKI diagnosed by the KDIGO criterion maintained this significant association (HR= 1.89 [95% CI: 1.18 - 3.06]).

Conclusion

The incidence and risk factors for AKI after cardiac surgery vary significantly according to the diagnostic criteria used. In our analysis, the KDIGO criterion was superior to AKIN and RIFLE with regard its prognostic power.

The association between atherosclerotic renal artery stenosis and acute kidney injury in patients undergoing cardiac surgery

BACKGROUND

Atherosclerotic renal artery stenosis (ARAS) and coronary artery disease (CAD) commonly co-exist. Some patients with unidentified ARAS may undergo cardiac surgery. While acute kidney injury (AKI) is a frequent and serious complication of cardiac surgery, we aim to evaluate the influence of ARAS on the occurrence of postoperative AKI in patients with normal or near-normal baseline renal function following cardiac surgery.

METHODS

A total of 212 consecutive patients undergoing aortography after coronary angiography and cardiac surgery were retrospectively studied for their preoperative and intraoperative conditions. AKI was defined as an absolute increase in serum creatinine of more than or equal to 0.3 mg/dl (≥26.4 µmol/l) or a percentage increase in creatinine of more than or equal to 50% (1.5-fold from baseline) after cardiac surgery. A propensity score-adjusted logistic regression models was used in estimating the effect of ARAS on the risk of postoperative AKI.

RESULTS

ARAS (≥50%) was observed in 50 (23.6%) patients, and 83 (39.2%) developed AKI after cardiac surgery. A correlation existed between renal artery patency and preoperative-to-postoperative %ΔCr in patients with ARAS (r = 0.297, P<0.0001). The propensity score-adjusted regression model showed the occurrence of postoperative AKI in patients with ARAS was significantly higher than those without ARAS (OR 2.858, 95% CI 1.260-6.480, P = 0.011).

CONCLUSION

ARAS is associated with postoperative AKI in patients with normal or near-normal baseline renal function after cardiac surgery.

Perioperative mortality in diabetic patients undergoing coronary artery bypass graft surgery

OBJECTIVE

To investigate the risk factors for in-hospital death in diabetic patients undergoing isolated Coronary Artery Bypass Grafting (CABG).

METHODS

We conducted a retrospective study with 305 consecutive diabetic patients undergoing CABG in the Division of Cardiovascular Surgery of our institution from April 2004 to April 2010. Univariate analysis for categorical variables was performed with the chi-square or Fisher's exact test, as appropriate. Potential risk factors with p <0.05 in the univariate analysis were included in the multivariate analysis, which was performed by backward logistic regression. Values of p <0.05 were considered statistically significant.

RESULTS

The study population had a mean age of 61.44 years (± 9.81) and 65.6% (n=200) were male. The in-hospital mortality rate was 11.8% (n=36). The following independent risk factors for death were identified: on-pump CABG (OR 6.15, 95% CI 1.57 to 24.03, P=0.009) and low cardiac output in the postoperative period (OR 34.17, 95% CI 10.46 to 111.62, P <0.001). The use of internal thoracic artery (ITA) was an independent protective factor for death (OR 0.27, 95% CI 0.08 to 0.093, P=0.038).

CONCLUSION

This study identified the following independent risk factors for death after CABG: on-pump CABG and low cardiac output syndrome. The use of ITA was an independent protective factor.

On-Pump versus Off-pump Myocardial Revascularization in Patients with Renal Insufficiency: Early and Mid-term Results

Background

Myocardial revascularization in patients with renal insufficiency is challenging to the cardiac surgeon, irrespective of utilizing extracorporeal circulation. This study aimed to compare the number of bypass grafts and the mid-term results and to evaluate independent survival predictors in patients with renal insufficiency undergoing on-pump or off-pump myocardial revascularization.

Materials and Methods

We retrospectively analyzed the data of 103 patients with renal insufficiency, who had isolated myocardial revascularization between January 1999 and January 2009. The patients were divided into two groups, the on-pump group and the off-pump group.

Results

The off-pump group received a significantly greater number of distal arterial grafts than the on-pump group. However, the mean number of total grafts, the degree of complete revascularization, and survival rate of the patients were not significantly different between the two groups. Multivariate analysis showed the independent predictors for reduced mid-term survival were the number of total grafts and postoperative periodic renal replacement therapy. Off-pump myocardial revascularization does not decrease the number of bypass grafts or influence on the mid-term results for patients with renal insufficiency, compared to on-pump myocardial revascularization.

Conclusion

Myocardial revascularization with a large number of total grafts has a beneficial effect on survival in patients with renal insufficiency, irrespective of utilizing extracorporeal bypass.

Impact of preoperative renal dysfunction in patients undergoing off-pump versus on-pump coronary artery bypass

BACKGROUND

The impact of the degree of renal dysfunction (RD) in patients undergoing coronary artery bypass grafting (CABG) ranging from normal to dialysis-dependence is not well defined.

METHODS

A retrospective review of 14,199 patients undergoing isolated, primary CABG from January 1996 to May 2009 at Emory Healthcare was performed. The estimated glomerular filtration rate (eGFR) was estimated by the Modification of Diet in Renal Disease formula: mild RD (eGFR 60 to 90 mL/min/1.73 m2), moderate RD (eGFR 30 to 59), severe RD (eGFR<30). A propensity scoring was used to balance the groups with 46 preoperative covariates. Multivariable logistic and Cox regression methods were used to determine the independent association of eGFR with mortality. Adjusted odds ratios were calculated for outcomes using the normal eGFR group as the reference. Kaplan-Meier curves were created to estimate long-term survival.

RESULTS

A total of 8,086 patients (57.0%) underwent off-pump coronary artery bypass (OPCAB) while 6,113 (43.0%) underwent on-pump CAB. Preoperative RD was common: Normal eGFR (n=3,503/14,199 [24.7%]); mild RD (7,236/14199 [51.0%]); moderate RD (2,860/14,199 [20.1%]); severe RD (283/14,199 [2.0%]); and preoperative dialysis (317/14,199 [2.2%]). Moderate to severe RD or preoperative dialysis was associated with worse adjusted in-hospital mortality: mild RD (odds ratio [OR] 1.42; 95% confidence interval [CI] 0.93 to 2.16; p=not significant); moderate RD (OR 3.55; 95% CI 2.32 to 5.43; p<0.05]; severe RD (OR 8.84; 95% CI 4.92 to 15.9; p<0.05); and dialysis-dependent (OR 9.64; 95% CI 5.45 to 17.0; p<0.05). Adjusted long-term survival was worse across levels of RD. The OPCAB patients with moderate to severe RD had worse long-term survival than on-pump CAB patients; however, the surgery types were similar among normal, mild, and dialysis patients.

CONCLUSIONS

Preoperative RD is common in the CABG population and is associated with diminished long-term survival. Improved early outcomes in patients with RD undergoing OPCAB diminished with worsening RD.

Preoperative Statins and Acute Kidney Injury After Cardiac Surgery: Utilization of a Consensus Definition of Acute Kidney Injury

Background

Previous trials investigating preoperative statin use for prevention of acute kidney injury following cardiovascular surgery were limited to patients undergoing a specific procedure and many used nonconsensus definitions of acute kidney injury.

Objective

To use a consensus definition of acute kidney injury for evaluating the association of preoperative statin use with the development of acute kidney injury following cardiac surgery utilizing cardiopulmonary bypass.

Methods

We retrospectively evaluated a cohort of 667 patients ≥18 years who underwent any cardiac surgery on cardiopulmonary bypass between April 2007 and May 2009 at Mercy Hospital in Scranton, PA. Patients were excluded if they were receiving preoperative renal replacement therapy, had stage 5 chronic kidney disease, or did not have a postoperative serum creatinine level assessed. The primary outcome was the odds of developing acute kidney injury given the use of preoperative statins. Acute kidney injury was defined based on the Acute Kidney Injury Network criteria as either an absolute increase in serum creatinine of ≥0.3 mg/dL or 1.5 times baseline, or the need for postoperative renal replacement therapy.

Results:

The final analysis included 563 patients; 356 were receiving preoperative statins. The incidence of acute kidney injury was 35.1% in the statin group and 26.1% in the non-statin group. On univariate analysis statins were associated with an increase in the odds of acute kidney injury (OR 1.53; 95% CI 1.05 to 2.24). Multivariate logistic regression did not demonstrate an association of statins with acute kidney injury (OR 1.36; 95% CI 0.904 to 2.05). Repeating the analysis using 312 propensity score–matched patients also showed no association of statins with acute kidney injury (OR 1.17; 95% CI 0.715 to 1.93).

Conclusions:

Our findings do not support the hypothesis that preoperative statin use is associated with a decrease in the incidence of acute kidney injury following cardiac surgery utilizing cardiopulmonary bypass.

Off-pump coronary artery bypass surgery and acute kidney injury: a meta-analysis of randomized and observational studies

BACKGROUND

Acute kidney injury (AKI) after coronary artery bypass grafting (CABG) is associated with significant morbidity and mortality. Controversy exists regarding whether an off-pump technique can reduce post-CABG renal injury.

STUDY DESIGN

Systematic review and meta-analysis.

SETTING & POPULATION

Adult patients undergoing CABG.

SELECTION CRITERIA FOR STUDIES

MEDLINE, EMBASE, Cochrane Renal Library, and Google Scholar were searched in May 2008 for randomized controlled trials (RCTs) and observational studies comparing off-pump CABG (OPCAB) with conventional CABG (CAB) for renal outcomes. Studies involving patients on long-term renal replacement therapy (RRT) were excluded.

INTERVENTION

OPCAB.

OUTCOMES

Primary outcomes were overall AKI and AKI requiring RRT.

RESULTS

22 studies (6 RCTs and 16 observational studies) comprising 27,806 patients met the inclusion criteria. The pooled effect from both study cohorts showed a significant reduction in overall AKI (odds ratio [OR], 0.57; 95% confidence interval [CI], 0.43 to 0.76; P for effect < 0.001; I(2) = 67%; P for heterogeneity < 0.001) and AKI requiring RRT (OR, 0.55; 95% CI, 0.43 to 0.71; P for effect < 0.001; I(2) = 0%; P for heterogeneity = 0.5) in the OPCAB group compared with the CAB group. In RCTs, overall AKI was significantly reduced in the OPCAB group (OR, 0.27; 95% CI, 0.13 to 0.54); however, no statistically significant difference was noted in AKI requiring RRT (OR, 0.31; 95% CI, 0.06 to 1.59). In the observational cohort, both overall AKI (OR, 0.61; 95% CI, 0.45 to 0.81) and AKI requiring RRT (OR, 0.54; 95% CI, 0.40 to 0.73) were significantly less in the OPCAB group. RCTs were noted to be underpowered and biased toward recruiting low-risk patients. Sensitivity analysis restricted to good-quality studies showed a significant reduction in AKI.

LIMITATIONS

Lack of uniform AKI definition in the included studies, heterogeneity for overall AKI outcome.

CONCLUSIONS

Analysis of the current evidence suggests a reduction in AKI using the OPCAB technique; however, studies lack consistency in defining AKI. Available RCTs are underpowered to detect a difference in AKI requiring RRT; evidence from observational studies suggests a reduction in RRT requirement. Future studies should apply a standard definition of AKI and target a high-risk population.

Renal outcome following on- and off-pump coronary artery bypass graft surgery

A prospective study was carried out to compare the outcomes of patients with preexisting non-dialysis-dependent renal dysfunction who underwent coronary artery bypass grafting with or without cardiopulmonary bypass. Elective off-pump coronary artery bypass was performed in 29 patients with renal dysfunction. Their results were compared with those of a similar group of 35 patients who underwent the conventional on-pump coronary artery grafting. There was a significant deterioration in creatinine clearance in the on-pump group on days 1, 2, and 4 after surgery, while creatinine clearance in the off-pump group remained close to the baseline level. Both groups had improved to the preoperative creatinine clearance values on follow-up at 4 weeks. It was concluded that off-pump surgery provided better renal protection than the conventional on-pump technique in patients with preexisting non-dialysis-dependent renal dysfunction.

Effect of aprotinin on renal dysfunction in patients undergoing on-pump and off-pump cardiac surgery: a retrospective observational study

BACKGROUND

Aprotinin is used during cardiac surgery for its blood-saving effects. However, reports suggest a possible association between use of this drug and increased renal dysfunction and mortality. We investigated the effect of aprotinin on renal dysfunction in cardiac surgery, considering the cofactors on-pump versus off-pump surgery and co-medication with angiotensin-converting enzyme (ACE) inhibitors.

METHODS

Our analysis included 9875 patients undergoing on-pump or off-pump cardiac surgery from Jan 1, 2000, to Sept 30, 2007. Of these patients, 9106 were included in the retrospective observational study analysis. With propensity-adjusted, multivariate staged logistic regression, we analysed separately the incidence of renal dysfunction in patients receiving aprotinin, tranexamic acid, or no antifibrinolytic treatment in the presence or absence of preoperative ACE inhibitor treatment, for both on-pump and off-pump surgical techniques.

FINDINGS

In 5434 patients undergoing on-pump cardiac surgery, the odds ratio (OR) between aprotinin and an increased risk of renal dysfunction without ACE inhibitor was 1.81 (95% CI 0.79-4.13, p=0.162) and with ACE inhibitor 1.73 (0.56-5.32, p=0.342). In the 848 patients taking ACE inhibitors and undergoing off-pump cardiac surgery, aprotinin was associated with a greater than two-fold increase in the risk of renal dysfunction after off-pump cardiac surgery (OR 2.87 [1.25-6.58], p=0.013).

INTERPRETATION

Our results have shown that aprotinin seems to be safe during on-pump cardiac surgery. However, the combination of aprotinin and ACE inhibitors during off-pump cardiac surgery is associated with a significant risk of postoperative renal dysfunction.

Acute kidney injury prediction following elective cardiac surgery: AKICS Score

Acute kidney injury (AKI) following cardiac surgery (AKICS) is associated with increased postoperative (post-op) morbidity and mortality. A prognostic score system for AKI would help anticipate patient (pt) treatment. To develop a predictive score (AKICS) for AKI following cardiac surgery, we used a broad definition of AKI, which included perioperative variables. Six hundred three pts undergoing cardiac surgery were prospectively evaluated for AKI defined as serum creatinine above 2.0 mg/dl or an increase of 50% above baseline value. Univariate and multivariate analyses were used to evaluate pre-, intra-, and post-op parameters associated with AKI. The AKICS scoring system was prospectively validated in a new data set of 215 pts with an incidence of AKI of 14%. Variables included in the AKICS score were age greater than 65, pre-op creatinine above 1.2 mg/dl, pre-op capillary glucose above 140 mg/dl, heart failure, combined surgeries, cardiopulmonary bypass time above 2 h, low cardiac output, and low central venous pressure. The AKICS score presented good calibration and discrimination in both the study group and validation data set. The AKICS system that we developed, which incorporates five risk categories, accurately predicts AKI following cardiac surgery.

Renal outcome in off-pump coronary artery bypass grafting: predictors for renal impairment with multivariate analysis

OBJECTIVE

: Recent studies on the efficacy of off-pump coronary artery bypass grafting (OPCABG) have reported encouraging results on postoperative renal function, but improvements can still be made.

METHODS

: A total of 368 patients, none needing chronic dialysis, underwent isolated OPCABG at our institution between January 1999 and March 2005. They were divided into 3 groups according to renal function as indicated by the serum creatinine levels: group N (n = 332) with normal function, group M (n = 30) with mild to moderate renal dysfunction, and group S (n = 6), with severe renal dysfunction. Creatinine ratio and early outcomes were compared among the groups. Predictors for renal impairment were determined by multiple regression analysis.

RESULTS

: In-hospital mortality rate was similar (group N, 0.6%; group M, 0%; group S, 0%). The percentage of patients with a creatinine ratio greater than 1.6 was significantly larger in group S (group N, 13%; group M, 13%; group S, 50%; P < 0.05). Postoperative hemodialysis, which was temporary, was required more frequently in group S (group N, 0.3%; group M, 3%; group S, 67%; P < 0.05). In group N, 38 patients (11%) had new renal impairment after OPCABG. Preoperative serum creatinine levels ≥2.5 mg/dL, ejection fraction <0.4, amount of blood transfusion, and more than 4 bypasses were potent predictors for postoperative renal impairment.

CONCLUSIONS

: Clinical results of OPCABG on renal function were satisfactory regardless of preoperative renal function. However, perioperative renal function should be closely monitored in patients with known risk factors, even when OPCABG is performed.

Coronary artery bypass grafting with or without cardiopulmonary bypass in patients with preoperative non–dialysis dependent renal insufficiency: A randomized study

OBJECTIVE

Preoperative renal insufficiency is a predictor of acute renal failure in patients undergoing coronary artery revascularization with cardiopulmonary bypass. Off-pump coronary artery bypass grafting has been shown to be less deleterious than on-pump bypass in patients with normal renal function, but the effect of this technique in patients with non-dialysis dependent renal insufficiency in a randomized study is unknown.

METHODS

From August 2004 through October 2005, 116 consecutive patients with preoperative non-dialysis-dependent renal insufficiency (glomerular filtration rate measured using the Modification of Diet in Renal Disease equation [MDRD GFR] < or = 60 mL x min(-1) x 1.73 m(-2)) undergoing primary coronary artery bypass grafting were randomized to on-pump (n = 60) and off-pump (n = 56) groups. MDRD GFR and serum creatinine levels were measured preoperatively and postoperatively at days 1 and 5. The changes in renal function and clinical outcomes were compared between the two groups.

RESULTS

Preoperative characteristics were comparable between the two groups. The repeated-measures analysis of variance was performed on the data that showed worsening of renal function in the on-pump group compared with the off-pump group (serum creatinine, P < .000; glomerular filtration rate, P < .000). Further analysis of subgroups of patients with diabetes alone, hypertension alone, and combined hypertension and diabetes also showed significant deterioration renal function in the on-pump group compared with the off-pump group. In covariate analysis, diabetes has emerged as a significant covariate by serum creatinine criteria while compromised left ventricular function has emerged as a significant covariate by glomerular filtration rate criteria. These analyses showed that the use of cardiopulmonary bypass is significantly associated with adverse renal outcome (P < .000). Three patents required hemodialysis in the on-pump group and none in the off-pump group. The mean number of grafts per patient was 3.85 +/- 0.86 and 3.11 +/- 0.89 in the on-pump and off-pump groups, respectively (P < .001), but the indices of completeness of revascularization, 1.00 +/- 0.08 for off-pump coronary bypass and 1.01 +/- 0.08 for on-pump coronary bypass, were similar (P = .60).

CONCLUSIONS

This study suggests that on-pump as compared with off-pump coronary artery bypass grafting is more deleterious to renal function in diabetic patients with non-dialysis dependent renal insufficiency. MDRD GFR is a more sensitive investigation than serum creatinine levels to assess renal insufficiency in patients undergoing coronary bypass.

Preoperative intravenous hydration confers renoprotection in patients with chronic kidney disease undergoing cardiac surgery

Patients with chronic kidney disease (CKD) are at risk to develop acute renal failure (ARF) after open heart surgery. This complication is associated with high morbidity, mortality, and cost. Because the ability to concentrate urine is lost early in the progression of CKD, renal patients kept on fluid restriction prior to surgery may develop severe dehydration, a situation consistently found to be one of the most critical risk factors for postoperative ARF. Our goal was to investigate whether intravenous hydration for 12 h prior to cardiac surgery could prevent acute renal injury in patients with CKD. This is a prospective study in a tertiary cardiac surgery center. Forty-five patients admitted for elective open heart surgery with moderate-to-severe CKD, as evidenced by a quantified glomerular filtration rate less than 45 mL/min, were assigned using a 2/1 randomization process, to either receive an intravenous infusion of half-isotonic saline (1 mL/kg/h) for 12 h before the operation (hydration group, n = 30, 29 men, 64 + 1.7 years old), or to be simply kept on fluid restriction (control group, n = 15, 14 men, 64.2 + 2.8 years old). Groups were not different in clinical and intraoperative variables associated with postoperative renal injury. ARF developed in 8 of 15 (53%) patients in the control group, but in only 9 of the 30 (30%) patients in the hydration group. Four patients in the control group (27%), but no one in the hydration group, required dialysis after the operation (P < 0.01). Peak creatinine and blood urea nitrogen values were two to three times higher in the control group than in the hydration group. Preoperative intravenous hydration may ameliorate renal damage in patients with moderate-to-severe renal insufficiency undergoing cardiac surgery.

Off-pump coronary artery bypass grafting through sternotomy: for whom?

PURPOSE OF REVIEW

Off-pump coronary artery bypass grafting hopes to avoid morbidity associated with cardiopulmonary bypass, improving clinical outcomes. Yet its technical difficulty and unfamiliarity raise concern that adoption of off-pump coronary artery bypass might be associated with poorer outcomes. Both surgeon-specific and patient-related factors are believed to play roles in the success of off-pump coronary artery bypass. This review sought to elucidate these factors.

RECENT FINDINGS

Current prospective data suggest that both techniques have similar rates of mortality but off-pump coronary artery bypass does provide patients with a lower morbidity. Multiple prospective studies suggest a decrease in stroke rates for off-pump coronary artery bypass grafting. There is a consensus that certain patients will have better outcomes if done off-pump. Surgeon experience with the procedure does impact patient outcome.

SUMMARY

Though every patient must be dealt with on an individual basis, it would appear that almost any patient is a candidate for off-pump coronary artery bypass and that, given time and an appropriate desire, most any surgeon can perform the procedure.

Prospective multicentre evaluation of adverse outcomes following treatment for complicated diverticular disease

Background

The choice of operation for complicated diverticular disease is contentious. The aim of this study was to investigate adverse events following restorative (primary resection and anastomosis, PRA) and non-restorative (Hartmann's procedure, HP) surgery for complicated diverticular disease.

Methods

Five hundred and thirty-nine patients who presented with complicated diverticular disease in 42 centres over a 12-month period from January 2003 were considered for the study. Data were collected prospectively from 248 patients (46·0 per cent) who underwent PRA and 167 (31·0 per cent) who had HP. A propensity score was developed for case-mix adjustment. Multifactorial logistic regression was used to evaluate differences in operative outcomes.

Results

Mortality, surgical and medical complication rates were 4·0, 31·0 and 13·7 per cent respectively after PRA, and 23·4, 53·3 and 40·7 per cent for HP (all P &lt; 0·001). After adjusting for the propensity score, the HP group had a 2·1- and 1·9-fold increase in medical and surgical complications respectively compared with those who had PRA, whereas the operative mortality rate was not significantly different. Non-colorectal surgeons performed a significantly higher proportion of HPs in the non-elective setting than colorectal surgeons (80·6 versus 60·4 per cent; χ2 = 8·31, 1 d.f., P = 0·004).

Conclusion

PRA with or without a proximal diversion is more often performed non-electively by specialist colorectal surgeons. It may be a safe procedure for complicated diverticular disease in selected patients as it may be associated with fewer postoperative adverse events.

Functional renal outcome in on-pump and off-pump coronary revascularization: a propensity-based analysis

BACKGROUND

Since the advent of off-pump coronary artery bypass grafting (OPCAB), comparisons have been made between it and on-pump coronary artery bypass grafting. Some observe a lesser incidence of acute renal failure requiring renal replacement therapy with OPCAB whereas others do not. The objective was to compare the occurrence of renal adverse outcome between on-pump coronary artery bypass grafting and OPCAB. Renal adverse outcome was defined as minor (20% increase in serum creatinine from preoperative) or major (composite end point of postoperative serum creatinine >200 mumol/L or postoperative mechanical renal support).

METHODS

The study was based on 2,041 patients with no known preoperative renal disease having first-time isolated coronary artery bypass grafting of multiple coronary arteries between January 2001 and November 2003, at St. Mary's Hospital, Harefield Hospital, and Hammersmith Hospital, in West London; 1,224 patients had on-pump coronary artery bypass grafting and 817 patients had OPCAB. Selection bias for surgical technique was addressed by calculating the propensity score for each patient and using it as an independent variable for adjustment in the multivariate analysis. Univariate and multivariate ordered logistic regressions were used to identify factors associated with renal adverse outcome ordered as none, minor, and major.

RESULTS

The number of grafts was 3.22 +/- 0.82 for the on-pump coronary artery bypass grafting group and 3.35 +/- 0.95 for the OPCAB group. On-pump coronary artery bypass grafting and increasing age were found to be the strongest independent predictors (p < 0.001) of renal adverse outcome. Other independent predictors included hypertension (p = 0.005), diabetes (p = 0.032), and preoperative serum creatinine (p = 0.001). A left ventricular ejection fraction of 0.30 to 0.49 (p = 0.099) and an ejection fraction of 0.50 or greater (p < 0.001) were associated with decreased risk compared with patients with an ejection fraction of less than 0.30. Interestingly, the use of non-left internal mammary arterial conduits significantly decreased the likelihood of renal adverse outcome (p = 0.034).

CONCLUSIONS

The results of this propensity-based study show that the OPCAB technique may reduce the risk for minor and major renal adverse outcome after coronary artery bypass grafting.

A review of the application of propensity score methods yielded increasing use, advantages in specific settings, but not substantially different estimates compared with conventional multivariable methods

OBJECTIVE

Propensity score (PS) analyses attempt to control for confounding in nonexperimental studies by adjusting for the likelihood that a given patient is exposed. Such analyses have been proposed to address confounding by indication, but there is little empirical evidence that they achieve better control than conventional multivariate outcome modeling.

STUDY DESIGN AND METHODS

Using PubMed and Science Citation Index, we assessed the use of propensity scores over time and critically evaluated studies published through 2003.

RESULTS

Use of propensity scores increased from a total of 8 reports before 1998 to 71 in 2003. Most of the 177 published studies abstracted assessed medications (N=60) or surgical interventions (N=51), mainly in cardiology and cardiac surgery (N=90). Whether PS methods or conventional outcome models were used to control for confounding had little effect on results in those studies in which such comparison was possible. Only 9 of 69 studies (13%) had an effect estimate that differed by more than 20% from that obtained with a conventional outcome model in all PS analyses presented.

CONCLUSIONS

Publication of results based on propensity score methods has increased dramatically, but there is little evidence that these methods yield substantially different estimates compared with conventional multivariable methods.

[Should we avoid cardiopulmonary bypass with diabetic patients?]

In the peri-operative and post-operative course of coronary bypass operations, the diabetic patient is susceptible to complications that cause morbidity and mortality. Morbidity might best be conceptualized as the cumulative effect of the diabetic patient chronically at risk and a variety of surgically related insults, including surgical stress, anaesthesia, hypo- and hypertension, anaemia, dysrhythmias, de- or hyperhydration and cardiopulmonary bypass (CPB) that exceed the compensatory capacities of the patient. Because all these factors for adverse outcome coexist, it becomes difficult to determine which ones are most important. However, it is reasonable that, in the presence of generalized atherosclerosis affecting the aorta ascendens, carotids and the cerebral arteries, the interaction of CPB-associated embolization, hypoperfusion and inflammation may cause neurologic morbidity. Many physiologic alterations (such as non-pulsatile perfusion and hemodilution) occur during CPB and may worsen renal dysfunction in patients with diabetic nephropathy. Pulmonary dysfunctions, associated with diabetic microangiopathy, could be unmasked by atelectasis, capillary leak and other pathophysiological conditions developing after the use of extracorporeal circulation. Actually, there is evidence that with the avoidance of CBP and the use of adequate OPCAB (Off Pump Coronary Artery Bypass) techniques, by experienced teams, the incidences of neurological, renal and pulmonary complications decrease, in high-risk patients, e. g. diabetics, as well as in unselected cohorts. Because it is not possible to identify confidently those patients who are at risk for CPB-associated complications, we use a strategy where all CABG (Coronary Artery Bypass Grafting) are performed in OPCAB technique. The total OPCAB approach will in addition ascertain the development of organizational OPCAB routines and expertise. The process of re-engineering the unit towards total OPCAB needs systematic training and re-training of cardiac surgeons by surgeons, experienced in both, OPCAB surgery and knowledge transfer, according to the principles of continuing medical education (CME). Thus, the chances of the OPCAB technique improving the outcome of diabetic patients can be fully realized.

Symmetry™ Aortic Connector Devices and Acute Renal Injury: A Comparison of Renal Dysfunction After Three Different Aortocoronary Bypass Surgery Techniques

Although the pathogenesis of acute renal injury after cardiac surgery is multifactorial, atherosclerosis of the ascending aorta and embolic burden are strong independent predictors. Use of the Symmetry aortic connector device (ACD) for proximal anastomosis of coronary grafts may reduce ascending aortic atheroembolism. Therefore, we tested the hypothesis that off-pump coronary artery bypass (OPCAB) surgery performed using an ACD is associated with less postoperative renal dysfunction compared with conventional OPCAB or on-pump coronary artery bypass graft (CABG) surgery. Three-thousand-three-hundred consecutive patients undergoing non-emergent aortocoronary bypass surgery were retrospectively divided into three groups by surgical procedure; Group A: OPCAB with ACD (n = 124), Group B: standard OPCAB (n = 313), Group C: on-pump CABG (n = 2863). Postoperative peak fractional change in creatinine compared with baseline was used as a measure of renal outcome. Multivariable analysis did not identify ACD use as an independent predictor of postoperative peak fractional change in creatinine (P = 0.71), although the relationships of several known renal risk factors with postoperative peak fractional change in creatinine were confirmed. We could not find evidence that OPCAB surgery using ACDs reduces acute renal injury compared with standard OPCAB or CABG surgery.

Physiological comparison of off-pump and on-pump coronary artery bypass grafting in patients on chronic hemodialysis

OBJECTIVES

Despite the long-term benefit, the operative results of conventional coronary artery bypass grafting for chronic hemodialysis patients remain unsatisfactory. The efficacy of off-pump coronary artery bypass grafting for hemodialysis patients is yet to be determined. The purpose of this study was to investigate the postoperative physiology of off-pump coronary artery bypass grafting for hemodialysis patients.

METHODS

Twenty-five hemodialysis cases who underwent isolated coronary artery bypass grafting were reviewed. Fifteen of these patients underwent off-pump coronary artery bypass grafting (off-group) and 10 underwent on-pump coronary artery bypass grafting (on-group). Comparisons were made in cardiac function (cardiac index and stroke volume index), respiratory function (AaDO2), hemodialysis management (blood urea nitrogen, creatinine, right atrial pressure, pulmonary wedge pressure), and bleeding tendency (postoperative blood loss and blood transfusion).

RESULTS

There was no operative mortality, but 3 major postoperative complications occurred (2 sternal wound infections in the off-group and 1 pneumonia in the on-group). There was no difference in cardiac index or stroke volume index. AaDO2 was significantly lower in the off-group. Plasma concentrations of blood urea nitrogen and creatinine were similar between groups. Right atrial pressure was lower and pulmonary wedge pressure tended to be lower in the off-group. Postoperative bleeding and blood transfusion were similar between groups.

CONCLUSION

Our study confirmed that off-pump coronary artery bypass grafting is feasible for hemodialysis patients. Physiologic data showed that off-pump coronary artery bypass grafting might be effective in preserving postoperative lung oxygenation.

Renal Dysfunction in High-Risk Patients After On-Pump and Off-Pump Coronary Artery Bypass Surgery: A Propensity Score Analysis

BACKGROUND

Cardiopulmonary bypass may be a causal factor in the development of renal impairment after cardiac surgery. When acute renal failure requiring dialysis occurs after cardiac surgery, it is associated with high mortality. We attempted to determine whether off-pump coronary artery bypass grafting surgery prevents postoperative renal dysfunction in patients at high risk for renal failure.

METHODS

Retrospective analysis identified 2,869 patients who had preexisting renal dysfunction (preoperative creatinine clearance less than 60 mL/min) and who underwent isolated coronary artery bypass grafting between 1995 and 2003. Patients who required preoperative dialysis were excluded. Propensity scores were computed to match off-pump coronary artery bypass surgery patients 3:1 with those who underwent conventional coronary artery bypass grafting surgery, and the independent predictors of postoperative renal dysfunction were determined.

RESULTS

Two thousand seven hundred eleven patients with preexisting renal dysfunction underwent conventional coronary artery bypass grafting surgery, and 158 patients underwent coronary artery bypass grafting surgery without cardiopulmonary bypass (off-pump coronary artery bypass grafting surgery group). The matched groups showed no differences in any of the preoperative or postoperative variables examined. Diabetes (odds ratio, 1.96; p = 0.01), peripheral vascular disease (odds ratio, 2.50; p < 0.001), and reduced preoperative creatinine clearance (odds ratio, 1.02; p = 0.02) were independent risk factors for the development of postoperative renal dysfunction. Off-pump coronary artery bypass grafting surgery was not associated with a decreased risk of renal dysfunction by univariate or multivariable analysis.

CONCLUSIONS

Off-pump coronary artery bypass grafting surgery did not reduce the risk of postoperative renal dysfunction in this large, unselected, sequential series of patients at high risk for renal failure after coronary artery bypass grafting surgery. Our results suggest that renal function should not be a deciding factor when determining whether or not a patient undergoes off-pump coronary artery bypass grafting surgery.

Outcome of Coronary Artery Bypass Operations in Patients With Renal Insufficiency With and Without Renal Transplantation

HYPOTHESIS

Renal insufficiency (RI) is associated with an increased risk of morbidity and mortality following coronary artery bypass graft (CABG) operations, particularly among patients who are dependent on dialysis.

DESIGN AND SETTING

A retrospective analysis of data collected at a tertiary care center.

PATIENTS

One hundred eighty-four consecutive patients with RI who underwent CABG surgery between 1992 and 2004. This group consisted of 152 patients with serum creatinine levels of > or = 1.7 mg/dL (group I) and 32 kidney transplant recipients (group II). Of the patients in group I, 90 were dialysis-free (subgroup IA) and 62 were dialysis-dependent (subgroup IB).

MAIN OUTCOME MEASURES

Demographics, perioperative data, and outcomes for each of the three groups were evaluated and compared.

RESULTS

Fifty-four percent of the patients were in New York Heart Association classes III and IV, 36% had unstable angina, and 21% had left main coronary disease. The mean ejection fraction was 38%. The median postoperative length of stay in the hospital was 10 days. Of the patients in group IB, 8% required reexploration for bleeding compared to 3% in groups IA and II (p < 0.05). Dialysis was needed postoperatively in five patients in group IA and two patients in group II (5.7%). The raw operative mortality rate was 7.6% and was higher in group IB (9.7%) compared to groups IA and II (6.7% and 6.2%, respectively; p < 0.05). The actuarial 5-year survival rate was higher in group II compared to group I (79% vs 59%, respectively; p < 0.05). The difference in survival rates was more apparent between groups II and IB (79% vs 57%, respectively; p < 0.005).

CONCLUSIONS

CABG is associated with an increased rate of perioperative complications and mortality in patients with RI. Dialysis dependence is a major risk factor for patients undergoing CABG surgery. However, with acceptable surgical results, dialysis patients should not be denied CABG surgery. A survival advantage is demonstrated among patients with previous kidney transplants compared to those patients who are dependent on dialysis.

Off-pump coronary artery bypass grafting in patients with renal dysfunction

BACKGROUND

Renal dysfunction is a predictor of increased morbidity and mortality after coronary artery bypass grafting, whether it is dialysis-dependent or not. Several studies have shown the efficacy of off-pump technique in reducing morbidity and mortality in patients with renal dysfunction. However, the actual effect of renal dysfunction in off-pump coronary artery bypass grafting has not been well understood.

METHODS

We conducted a retrospective review of 402 consecutive patients undergoing off-pump coronary artery bypass grafting from April 2001 to June 2003. Sixty-eight patients had chronic renal dysfunction (group A); 19 patients were dialysis-dependent; 334 patients had normal renal function (group B). Operative variables, morbidity, and mortality were compared between the two groups. Furthermore, multivariable analysis was performed to identify predictors for short-term survival.

RESULTS

Preoperative characteristics were similar in the two groups. Blood transfusion rate was higher in group A than group B (57.4% and 25.7%, respectively; p < 0.001). In-hospital mortality was similar (1.5% and 1.2% in group A and B, respectively; p = 0.853). Multivariable analysis revealed that unstable angina, low ejection fraction, peripheral vascular disease and redo surgery are significant risk factors for poor early result of off-pump coronary artery bypass grafting.

CONCLUSIONS

Early outcomes of off-pump coronary artery bypass grafting in patients with renal dysfunction were comparable to those in patients with normal renal function. Renal dysfunction is not a predictor of poor early outcomes after off-pump coronary artery bypass grafting.