Association between diabetes and heart failure after coronary artery bypass grafting: Danish register-based cohort study

BACKGROUND

Ischemic heart disease (IHD) is the leading cause of mortality in the world with an increasing incidence. One of the interventions to treat IHD is coronary artery bypass grafting (CABG) and people with diabetes mellitus (DM) account for approximately one quarter of all patients who undergo coronary revascularization. Furthermore, people with DM have a higher risk of mortality due to heart failure (HF).

OBJECTIVE

We aim to describe the risk of developing HF after CABG in patients with versus without DM.

METHODS

Through a large nationwide register-based cohort study, patients who underwent CABG from January 1, 2000 to December 31, 2020 were included. In addition to Cox regression, g-formula methods based on multivariable Cox regression were performed to estimate the absolute risk (AR) and risk difference (RD) of the association between DM status and HF outcome, and between DM status and mortality.

RESULTS

A total of 34,855 patients were included in this study, consisting of 6909 (19.8%) DM patients. The AR of HF after CABG in the 10th year was 35.1% versus 26.4% for patients with versus without DM (p < 0.001), respectively. The RD of HF for each exceeding year (3.7 percentage point (pp.) in the 1st year versus 8.6 pp. in the 10th year) was higher for patients with DM compared to those without DM.

CONCLUSION

The risk of HF was significantly higher up to ten years after CABG in patients with DM compared to those without DM.

Long-term mortality after isolated coronary artery bypass grafting and risk factors for mortality

BACKGROUND

Patients requiring coronary artery bypass grafting (CABG) have multiple co-morbidities which need to be considered in totality when determining surgical risks. The objective of this study is to evaluate short-term and long-term mortality rates of CABG surgery, as well as to identify the most significant risk factors for mortality after isolated CABG.

METHODS

All patients with complete dataset who underwent isolated CABG between January 2008 and December 2017 were included. Univariate and multivariate Cox regression was performed to determine the risk factors for all-cause mortality. Classification and regression tree analysis was performed to identify the relative importance of these risk factors.

RESULTS

3,573 patients were included in the study. Overall mortality rate was 25.7%. In-hospital mortality rate was 1.62% overall. 30-day, 1-year, 5-year, 10-year and 14.5-year mortality rates were 1.46%, 2.94%, 9.89%, 22.79% and 36.30% respectively. Factors associated with death after adjustment for other risk factors were older age, lower body mass index (BMI), hypertension, diabetes mellitus, chronic obstructive pulmonary disease, pre-operative renal failure on dialysis, higher last pre-operative creatinine level, lower estimated glomerular filtration rate (eGFR), heart failure, lower left ventricular ejection fraction and New York Heart Association class II, III and IV. Additionally, female gender and logistic EuroSCORE were associated with death on univariate Cox analysis, but not associated with death after adjustment with multivariate Cox analysis. Using CART analysis, the strongest predictor of mortality was pre-operative eGFR < 46.9, followed by logistic EuroSCORE ≥ 2.4.

CONCLUSION

Poorer renal function, quantified by a lower eGFR, is the best predictor of post-CABG mortality. Amongst other risk factors, logistic EuroSCORE, age, diabetes and BMI had a relatively greater impact on mortality. Patients with chronic kidney disease stage 3B and above are at highest risk for mortality. We hope these findings heighten awareness to optimise current medical therapy in preserving renal function upon diagnosis of any atherosclerotic disease and risk factors contributing to coronary artery disease.

Impact of diabetic versus non-diabetic patients undergoing coronary artery bypass graft surgery on postoperative wound complications: A meta-analysis

The effect of diabetes mellitus (DM) on the incidence of postoperative wound complications in patients with coronary artery bypass grafting (CABG) is still unclear. Thus, we performed a meta-analysis of CABG in DM patients to evaluate existing data from both prospective and historical cohorts. The objective of this trial was to assess the relevance and extent of the effect of diabetes on the outcome of previous CABG procedures. Data sources like Embase and Pubmed were found throughout the research, and the language was limited to English through manual search. The searches were performed up to August 2023. The data were extracted from the study of the inclusion/exclusion criteria, the features of the population, the statistical approach and the clinical results. A qualitative evaluation of the qualifying studies has been carried out. Out of the 1874 studies identified, 21 cohort studies were chosen for analysis. Meta-analyses were performed in 258 454 patients (71 351 diabetic and 187 103 non-diabetic). Twenty-one studies on deep sternal wound infections in CABG patients showed a lower rate of deep sternal wound infections in non-diabetes group compared with those with diabetes (OR, 2.13; 95% CI: 1.97, 2.31, p < 0.00001). And 16 studies of superficial wound infections in patients undergoing CABG were found to be associated with a lower rate of superficial injury (OR, 1.93; 95% CI: 1.53, 2.43, p < 0.00001) compared with those with diabetes; In five trials, perfusion time during CABG (MD, 2.31; 95% CI: -0.16, 4.79, p = 0.07) was observed, and there were no significant differences between diabetes and non-diabetes. Currently, there is a higher risk for CABG in diabetes than in non-diabetes patients with sternal infections and superficial injuries. Future randomized trials will concentrate on the treatment of such perioperatively related complications, which will lower the risk of postoperative wound infection in diabetes.

Long-Term Outcomes of Coronary Artery Bypass Grafting Using an Internal Thoracic Artery versus a Radial Artery as a Second Arterial Graft

PURPOSE

To compare the outcomes of left circumflex artery (LCx) revascularization using an internal thoracic artery (ITA) or radial artery (RA) as the second arterial graft.

METHODS

Patients who underwent primary isolated coronary artery bypass grafting with left anterior descending artery revascularization using an ITA and LCx revascularization using another bilateral ITA (BITA group) or an RA (ITA-RA group) were included. All-cause mortality (primary endpoint), cardiac death, major adverse cardiac events, in-hospital death, and deep sternal wound infection (secondary endpoints) were evaluated.

RESULTS

Among 790 patients (BITA, n = 548 (69%); ITA-RA, n = 242 (31%)), no significant difference in all-cause mortality between the groups was observed (hazard ratio (HR): 0.87; 95% confidence interval (CI): 0.67-1.12; p = 0.27) during follow-up (mean, 10 years). Multivariate analysis revealed that the BITA group exhibited significantly lower rates of long-term all-cause mortality (HR: 0.63; 95% CI: 0.48-0.84; p = 0.01). In the propensity-matched cohort (n = 480, 240 pairs), significantly fewer all-cause deaths occurred in the BITA group (HR: 0.66; 95% CI 0.47-0.93; p = 0.02). There were no significant differences in secondary outcomes.

CONCLUSIONS

When used as second grafts for LCx revascularization, ITA grafts may surpass RA grafts in reducing all-cause mortality 10 years postoperatively.

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.

Sleep apnea and diabetes mellitus are independently associated with cardiovascular events and hospitalization for heart failure after coronary artery bypass grafting

The relative and combined effects of sleep apnea with diabetes mellitus (DM) on cardiovascular outcomes in patients undergoing coronary artery bypass grafting (CABG) remain unknown. In this secondary analysis of data from the SABOT study, 1007 patients were reclassified into four groups based on their sleep apnea and DM statuses, yielding 295, 218, 278, and 216 patients in the sleep apnea (+) DM (+), sleep apnea (+) DM (−), sleep apnea (−) DM (+), and sleep apnea (−) DM (−) groups, respectively. After a mean follow-up period of 2.1 years, the crude incidence of major adverse cardiac and cerebrovascular event was 18% in the sleep apnea (+) DM (+), 11% in the sleep apnea (+) DM (−), 13% in the sleep apnea (−) DM (+), and 5% in the sleep apnea (−) DM (−) groups. Using sleep apnea (−) DM (−) as the reference group, a Cox regression analysis indicated that sleep apnea (+) and DM (+) independently predicted MACCEs (adjusted hazard ratio, 3.2; 95% confidence interval, 1.7–6.2; p = 0.005) and hospitalization for heart failure (adjusted hazard ratio, 12.6; 95% confidence interval, 3.0–52.3; p < 0.001). Sleep apnea and DM have independent effects on the prognosis of patients undergoing CABG.

Clinical trial registration: ClinicalTrials.gov identification no. NCT02701504.

Long-term outcomes after coronary artery bypass surgery in patients with diabetes

OBJECTIVES

Our aim was to investigate the outcome of patients with diabetes undergoing coronary artery bypass grafting (CABG) surgery in a whole population with main focus on long-term mortality and complications.

METHODS

This was a nationwide retrospective analysis of all patients who underwent isolated primary CABG in Iceland between 2001 and 2016. Overall survival together with the composite end point of major adverse cardiac and cerebrovascular events was compared between patients with diabetes and patients without diabetes during a median follow-up of 8.5 years. Multivariable regression analyses were used to evaluate the impact of diabetes on both short- and long-term outcomes.

RESULTS

Of a total of 2060 patients, 356 (17%) patients had diabetes. Patients with diabetes had a higher body mass index (29.9 vs 27.9 kg/m2) and more often had hypertension (83% vs 62%) and chronic kidney disease (estimated glomerular filtration rate ≤60 ml/min/1.73 m2, 21% vs 14%). Patients with diabetes had an increased risk of operative mortality [odds ratio 2.52, 95% confidence interval (CI) 1.27-4.80] when adjusted for confounders. 5-Year overall survival (85% vs 91%, P < 0.001) and 5-year freedom from major adverse cardiac and cerebrovascular events were also inferior for patients with diabetes (77% vs 82%, P < 0.001). Cox regression analysis adjusting for potential confounders showed that the diagnosis of diabetes significantly predicted all-cause mortality [hazard ratio (HR) 1.87, 95% CI 1.53-2.29] and increased risk of major adverse cardiac and cerebrovascular events (HR 1.47, 95% CI 1.23-1.75).

CONCLUSIONS

Patients with diabetes have significantly lower survival after CABG, both within 30 days and during long-term follow-up.

Did blood transfusion increase mortality in patients with diabetes undergoing isolated coronary artery bypass graft surgery? A propensity score-matched analysis of 816 patients

Background

The aim of this study was to compare clinical outcomes of blood transfusion in patients with diabetes mellitus undergoing isolated on-pump coronary artery bypass grafting.

Methods

The medical records of a total of 1,912 patients (1,300 males, 612 females; mean age 60.7±10.0) with diabetes who underwent isolated on-pump coronary artery bypass grafting between January 1999 and June 2019 were retrospectively analyzed. The patients were divided into two groups as patients with and without blood transfusions. The mortality rates were compared between the two groups.

Results

The mortality rate was 14 times higher in the patients receiving blood transfusion (odds ratio: 14.80; 95% confidence interval 5.05 to 43.34; p<0.001). However, in the multivariate logistic regression analysis, there were no statistically significant difference in mortality between the patient groups, when diabetes mellitus was a covariate factor (Odds ratio: 8.34; 95% confidence interval 3.94 to 17.66 vs. odds ratio 8.36; 95% confidence interval 3.95 to 17.70).

Conclusion

The propensity score-matched analysis of patients with diabetes showed that clinical outcomes were more severely affected by blood transfusion.

The impact of diabetes mellitus on acute kidney injury after coronary artery bypass grafting

Background

Diabetes mellitus(DM) is an indicator affects postoperative mortality and morbidity after coronary artery bypass grafting (CABG). Acute kidney injury (AKI) is one of the frequent postoperative complications after CABG. This multi-centre register study designed to investigate the impact of DM on postoperative AKI in primary isolated CABG patients.

Methods

We included all patients (n = 4325) from Jiangsu Province CABG register who underwent primary isolated CABG from September 2017 to August 2019. The patients were divided into 3 groups: No-DM group(n = 3067), DM-oral group (DM with oral hypoglycemic agents, n = 706) and DM-insulin group (DM with insulin treatment, n = 552). The development and severity of AKI were based on Acute Kidney Injury Network (AKIN) criteria.

Results

There were totally 338, 108 and 145 patients developed AKI in No-DM, DM-oral and DM-insulin group respectively. Comparing with No-DM group, DM-oral group had a higher rate of AKI(χ² = 10.071, p = 0.002), DM-insulin group had a higher rate(χ² = 94.042, p<0.001) and severity of AKI(χ² = 10.649, p = 0.005). The adjusted odds ratio for AKI was 1.26 (95% CI 1.03–1.57) in DM-oral group and 3.92 (95% CI 3.27–5.16) in DM-insulin group, in comparison with No-DM group.

Conclusions

Independent of baseline renal function or cardiac function, DM was associated with an increased risk of AKI after CABG, especially in patients with insulin treatment, who also had a higher severity of AKI.

Kidney function is associated with short-term, mid-term and long-term clinical outcome after coronary angiography and intervention

BACKGROUND

Patients with kidney dysfunction are at risk of developing ischaemic heart disease. We investigated the association between eGFR and early-, mid- and long-term clinical outcome in patients undergoing coronary angiography and intervention.

METHODS

Retrospective study on 4968 patients with complete data on eGFR, 65% male and aged 32-80 years, admitted to Danderyd University Hospital, Stockholm, Sweden for coronary angiography and intervention from 2006 to 2008. Data were censored at 0-30 days, 31-365 days and 366-1825 days of follow-up.

RESULTS

Baseline eGFR was strongly associated with all-cause mortality at all three time periods studied with each 10 ml/min per 1.73 m² increase in eGFR being associated with a ∼30% (p < .001), 25% (p = .002) and 20% (p < .001) decrease in all-cause mortality at 30, 365 and 1825 days respectively. Each 10 ml/min per 1.73 m² increase in eGFR was associated with a ∼21% (p < .001) decrease in re-hospitalisation for MI at 365 days and a 6% decrease (p = .03) at day 30 for re-vascularisation.

CONCLUSIONS

We report a strong association between kidney function and all-cause mortality at both early, mid- and long-term follow-up in patients undergoing coronary angiography and intervention, with eGFR significantly associated with MI-related mortality after one month of follow-up. Kidney function was also shown to be associated with risk for re-vascularisation at one month, indicating mostly procedural-related risk and with new MI at mid-term follow-up. Further research is warranted to explore the mechanisms linking kidney function and cardiovascular disease to improve both the short- and long-term care of these patients.

Years of Life Lost After Complications of Coronary Artery Bypass Operations

BACKGROUND

We currently have an incomplete understanding of which postoperative complications after coronary artery bypass grafting (CABG) are associated with long-term death. The purpose of this study was to find the associations between complications and attributable death.

METHODS

Prospectively collected data on patient characteristics, risk factors, and complications of patients undergoing isolated CABG with 20-year follow-up were analyzed with a Cox regression model to calculate the overall hazard of dying associated with each postoperative complication. An individual's age and hazard of dying from each complication were then used to calculate years of life lost to each complication.

RESULTS

The postoperative mortality rate was 0.79% (69 of 8,773) at 30 days, 2.85% (250 of 8,773) at 180 days, and 6.38% (560 of 8,773) at 2 years. At a median follow-up of 9.8 years, 1,891 patients (21.6%) had died. Postoperative complications occurred in 3,438 patients (39.2%). Cardiac arrest (hazard ratio, 2.153), reoperation (hazard ratio, 1.679), and new dialysis (hazard ratio, 1.64) were the complications with the greatest hazard of death. After adjusting for complication incidence and patient age, cardiac arrest (703 years), reoperation (544 years), atrial fibrillation (470 years), and prolonged mechanical ventilation (371 years) were associated with the greatest number of years of life lost.

CONCLUSIONS

Acute cardiac arrest, reoperation for other cardiac reasons, new dialysis, atrial fibrillation, and prolonged mechanical ventilation are associated with the largest increase in attributable deaths. Prevention and treatment of these complications may improve mortality rates after cardiac operations.

Current outcomes of off-pump coronary artery bypass grafting: evidence from real world practice

Coronary artery bypass grafting (CABG) can be performed conventionally using cardiopulmonary bypass (CPB) and aortic clamping or on a beating heart (BH) without the use of CPB, the so-called off-pump CABG. Some surgeons, who are proponents of off-pump CABG, preferentially use this technique for the majority of operations, whereas others use it only in certain situations which warrant avoidance of CPB. Ever since the conception of off-pump CABG, the never-ending debate about which technique of CABG is safe and efficacious continues to date. Several randomized controlled trials (RCTs) have been conducted that have either favored on-pump CABG or have failed to show a significant difference in outcomes between the two techniques. However, these RCTs have been fraught with claims that they do not represent the majority of patients undergoing CABG in real world practice. Therefore, assessment of the benefits and drawbacks of each technique through observational and registry studies would be more representative of patients encountered in daily practice. The present review examines various retrospective studies and meta-analyses of observational studies that compare the early and long-term outcomes of off- and on-pump CABG, which assesses their safety and efficacy. Additionally, their outcomes in older patients, females, and those with diabetes mellitus, renal dysfunction, presence of ascending aortic disease, and/or acute coronary syndrome (ACS) have also been discussed separately. The general consensus is that early results of off-pump CABG are comparable to or in some cases better than on-pump CABG. However, on-pump CABG provides a survival benefit in the long term according to a majority of publications in literature.

Prognosis and Complications of Diabetic Patients Undergoing Isolated Coronary Artery Bypass Surgery

Objective:

Compare the prognosis and complications of diabetic and non-diabetic patients undergoing isolated coronary artery bypass surgery at a hospital with a high surgical volume.

Methods:

Data of patients who underwent coronary artery bypass surgery from June 2009 to July 2010 were analyzed. We selected diabetic and non-diabetic patients and evaluated their postoperative and long-term prognosis based on clinical complications. To reduce the disparity within the sample, statistical analyses were performed using propensity scores.

Results:

We included 2,688 patients who underwent coronary artery bypass surgery; 36% of them had diabetes, their mean age was 62.1±9.49 years and 70% (1,884) of them were men. Patients with diabetes were older (63±9 years vs. 61±10 years; P<0.001), more often obese (BMI>25 kg/m²: 70.7% vs. 64.5%; P<0.001), dyslipidemic (50.4% vs. 41.1%; P<0.001), hypertensive (89.2% vs. 78.7%; P<0.001), and presented chronic renal failure (8.3% vs. 3.8%; P<0.001). They also presented higher rates of acute renal failure (5.6% vs. 2.7%, P<0.001), infection (11.4% vs. 7.2%, P<0.001) and mortality after one year (9.1% vs. 5.6%, P<0.001). Pneumonia was more common among patients with diabetes (7.7% vs. 4.0%, P<0.001). According to propensity scoring, 430 patients (215 diabetics and 215 non-diabetics) had a mean age of 61.3±8.97 years, and 21.2% (91 of 430) were women. However, diabetes was not an independent factor for poor prognosis.

Conclusion:

Patients with diabetes were at higher risk for postoperative complications and mortality after undergoing coronary artery bypass surgery. However, diabetes did not explain the poor prognosis of these patients after pairing this factor with the propensity score.

Existence of renal dysfunction in diabetics undergoing coronary artery bypass

INTRODUCTION

The effect of diabetes mellitus on morbidity and mortality in patients undergoing coronary artery bypass grafting has remained uncertain, and conflicting conclusions have been reported in clinical trials. Evidence suggests that coronary artery bypass in patients with diabetes mellitus carries a higher risk of stroke, renal failure, perioperative complications, and sternal wound infection. This study evaluated the frequency of acute renal dysfunction after coronary artery bypass in diabetic patients, and the associated risk factors.

METHOD

This cross-sectional observational study included 135 patients with diabetes (111 males and 24 females with a mean age 51 years and a body mass index of 27.44 kg m(-2)), who underwent elective coronary artery bypass from March 2015 to October 2015. Data were collected prospectively in 2 tertiary care centers. Renal dysfunction was assessed by serum creatinine levels preoperatively and at 24 and 48 h postoperatively.

RESULTS

Fifteen percent of patients were found to have postoperative renal dysfunction. Univariate analysis revealed that patients with increased serum creatinine preoperatively were at greater risk of developing renal dysfunction after coronary artery bypass (p = 0.00). On multivariable binary logistic regression analysis, preoperative serum creatinine level was the only independent predictor of postoperative renal dysfunction; age, body mass index, dyslipidemia, hypertension, cardiopulmonary bypass time, and aortic crossclamp time showed no significant association.

CONCLUSION

Diabetic patients with increased serum creatinine preoperatively are at greater risk of kidney damage postoperatively; therefore, these patients should be monitored and treated critically in the perioperative period.

Impact of mild preoperative renal insufficiency on in-hospital and long-term outcomes after off-pump coronary artery bypass grafting: a retrospective propensity score matching analysis

BACKGROUND

Mild preoperative renal insufficiency is not rare in patients receiving isolated off-pump coronary artery bypass grafting surgery (OPCAB) surgery. However, there is less study aimed to evaluate the impact of mild preoperative renal insufficiency on in-hospital and follow-up outcomes after isolated OPCAB surgery. This single-centre, retrospective propensity score matching study aimed to evaluate the impact of mild preoperative renal insufficiency on in-hospital and long-term outcomes after first isolated OPCAB surgery.

METHODS

After propensity score matching, 1236 patients with preoperative estimated glomerular filtration rate (eGFR) of more than 60 ml/min/1.73 m(2) undergoing first isolated OPCAB surgery from January 2007 to December 2011 were entered into this study and were divided to normal group (eGFR ≥ 90 ml/min/1.73 m(2), n = 618) and mild group (eGFR of 60-89 ml/min/1.73 m(2), n = 618). The in-hospital and long-term outcomes were investigated and retrospectively analyzed.

RESULTS

The 2 propensity score-matched groups had similar baseline and procedural characteristics except the baseline eGFR. Thirty-five patients died during the same hospitalization or within 30 days of operation, with a surgical mortality of 2.8 %. Sixty-seven patients died during follow-up, with a long-term survival of 94.1 %. Univariate factor analysis showed that the 2 propensity score-matched groups have similar rates among in-hospital outcomes. Kaplan-Meier curves displayed a similar in-hospital survival between the 2 groups (χ(2) = 0.728, p = 0.393), while a better long-term survival in patients with normal preoperative renal function compared with mild preoperative renal insufficiency (χ(2) = 4.722, p = 0.030). After Cox proportional model was used, the hazard ratio for long-term mortality in patients with mild preoperative renal insufficiency compared with normal preoperative renal function was 1.72 (95 % CI 1.06-2.83, p = 0.032).

CONCLUSIONS

Mild preoperative renal insufficiency compared with normal preoperative renal function reduced long-term survival, without evidence of worse in-hospital outcomes.

The effect of chronic renal insufficiency by use of glomerular filtration rate versus serum creatinine level on late clinical outcome of carotid endarterectomy

BACKGROUND

Several studies have reported mixed results after carotid endarterectomy (CEA) in patients with chronic renal insufficiency (CRI), and we previously reported the perioperative outcome in patients with CRI by use of serum creatinine (Cr) level and glomerular filtration rate (GFR). However, only a few of these studies used GFR by the Modification of Diet in Renal Disease equation in their analysis of long-term outcome.

METHODS

During the study period, 1000 CEAs (926 patients) were analyzed; 940 of these CEAs had Cr levels and 925 had GFR data. Patients were classified into normal (GFR ≥60 mL/min/1.73 m(2) or Cr <1.5 mg/dL), moderate CRI (GFR ≥30-59 or Cr ≥1.5-2.9), and severe CRI (GFR <30 or Cr ≥3).

RESULTS

At a mean follow-up of 34.5 months and a median of 34 months (range, 1-53 months), combined stroke and death rates for Cr levels (867 patients) were 9%, 18%, and 44% for Cr <1.5, ≥1.5 to 2.9, and ≥3 (P = .0001) in contrast to 8%, 14%, and 26% for GFR (854 patients) of >60, ≥30 to 59, and <30, respectively (P = .0003). Combined stroke and death rates for asymptomatic patients were 8%, 17%, and 44% (P = .0001) for patients with Cr levels of <1.5, ≥1.5 to 2.9, and ≥3, respectively, vs 7%, 13%, and 24% for a GFR of ≥60, ≥30 to 59, and <30 (P = .0063). By Kaplan-Meier analysis, stroke-free survival rates at 1 year, 2 years, and 3 years were 97%, 94%, and 92% for Cr <1.5; 92%, 85%, and 81% for Cr ≥1.5 to 2.9; and 56%, 56%, and 56% for Cr ≥3 (P < .0001); vs 98%, 95%, and 93% for a GFR ≥60; 93%, 90%, and 86% for a GFR of ≥30 to 59; and 86%, 77%, and 73% for a GFR <30 (P < .0001). These rates for asymptomatic patients at 1 year, 2 years, and 3 years were 97%, 95%, and 93% for Cr <1.5; 94%, 87%, and 82% for Cr ≥1.5 to 2.9; and 56%, 56%, and 56% for Cr ≥3 (P < .0001); vs 98%, 95%, and 94% for a GFR ≥60; 95%, 91%, and 86% for a GFR of ≥30 to 59; and 84%, 80%, and 75% for a GFR <30 (P = .0026). A univariate regression analysis for asymptomatic patients showed that the hazard ratio (HR) of stroke and death was 6.5 (P = .0003) for a Cr ≥3 and 3.1 for a GFR <30 (P = .0089). A multivariate analysis showed that Cr ≥3 had an HR of stroke and death of 4.7 (P = .008), and GFR <30 had an HR of 2.2 (P = .097).

CONCLUSIONS

Patients with severe CRI had higher rates of combined stroke/death. Therefore, CEA for these patients (particularly in asymptomatic patients) must be considered with caution.

Factors associated with in-hospital mortality after coronary artery bypass grafting in patients with CHD and type 2 diabetes

Coronary artery bypass grafting (CABG) is the main method used for myocardial revascularisation in patients with diabetes mellitus (DM), and determining the factors affecting the outcomes of CABG in these patients is important. Objective. To identify risk factors for in-hospital mortality after coronary artery surgery (CABG) for patients with and without type 2 diabetes mellitus (T2DM). Methods. A retrospective analysis of the medical records of patients who underwent CABG from 2006 to 2009 was conducted. From these, 317 patients with T2DM were selected (median age: 59,0 years). As a control group, 350 patients (median age: 58,0 years) without diabetes or pre-diabetes, who were matched by sex, age and CABG characteristics, were selected. Logistic regression models were used to identify factors possibly associated with in-hospital mortality. Results. There were no group differences for the frequency of postoperative complications and in-hospital mortality (p >0,05). During the early postoperative period, 5 (1,6%) diabetic and 7 (2,0%) non-diabetic patients died (p=0,682). By the logistic regression analysis, T2DM did not predict patient mortality (p=0,458). Among the patients with T2DM, a risk of death was associated with a stroke history (OR 21,661; 95% CI 1,701-76,521; р=0,013), and a decreased glomerular filtration rate (GFR) as estimated by the CKD-EPI equation (OR 1,512 per 5 ml/min/1,73m2.  decrease; 95% CI 1,017-2,257; р=0,048), independent of gender, age or triple-vessel and left-main disease. By multivariate analysis for the non-diabetic patients, the risk of death increased by more than 10 times because of reinfarction (OR=10,272; 95% CI: 1,258?56,163; p=0,029) and increased by 6,8 times with an increase in preoperative fibrinogen levels of 1 g/l (OR=6,802; 95% CI: 1,283?35,714; p=0,024), independent of gender, age, smoking or mitral valve regurgitation. Conclusions. T2DM was not a predictor of death during the early period after CABG. For the diabetic patients, independent predictors of in-hospital mortality after CABG were stroke history and reduced GFR. For the patients without T2DM, the independent predictors were reinfarction and preoperative fibrinogen levels.