Endotoxin release in cardiac surgery with cardiopulmonary bypass: pathophysiology and possible therapeutic strategies. An update

Cardiac surgery with cardiopulmonary bypass provokes a systemic inflammatory response syndrome caused by the surgical trauma itself, blood contact with the non-physiological surfaces of the extracorporeal circuit, endotoxemia, and ischemia. The role of endotoxin in the inflammatory response syndrome has been well investigated. In this report, we reviewed recent advances in the understanding of the pathophysiology of the endotoxin release during cardiopulmonary bypass and the possible therapeutic strategies aimed to reduce the endotoxin release or to counteract the inflammatory effects of endotoxin. Although many different strategies to detoxify endotoxins were evaluated, none of them were able to show statistically significant differences in clinical outcome. (C) 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved

Long-term results of coronary artery bypass grafting in patients with left ventricular dysfunction

Background. In this prospective study, we investigated the determinants of long-term outcome, symptoms, and left ventricular function after coronary artery bypass grafting in patients with a moderate to severely decreased left ventricular ejection fraction. Methods. Between 1997 and 1998, 75 consecutive patients with moderate to severe left ventricular dysfunction underwent coronary artery bypass grafting procedures. The operative mortality rate was 4.0%, and the 72 survivors were monitored for 8 years. The end points were mortality, symptomatic status (New York Heart Association [NYHA] functional class), and left ventricular function. Results. The total survival rate after 8 years was 89.3%. During follow-up, 8 patients died. Death was attributed to a cardiac cause in 5 patients and to a noncardiac cause in 3. There was no statistically significant difference between preoperative and late postoperative NYHA functional class, despite a statistically significant improvement that persisted for up to 4 years after CABG. The results of echocardiography showed a statistically significant improvement in the left ventricular ejection fraction (from 0.322 +/- 0.06 preoperatively to 0.463 +/- 0.02 at follow-up, p < 0.001). Multivariate analysis revealed that the left ventricular end-systolic volume index, the presence of angina pectoris, and absence of symptoms of congestive heart failure were preoperative indicators of freedom from heart failure after coronary operations (p < 0.05). Conclusions. Coronary artery bypass grafting for patients with moderate-to-severe left ventricular dysfunction is associated with acceptable long-term results. The left ventricular end-systolic volume index is a simple noninvasive method to aid in the preoperative decision making in such patients

Risk factors for deterioration of renal function after coronary artery bypass grafting

Objective: Various definitions of impairment of renal function after coronary artery bypass grafting (CABG) are used in the literature. Depending on the definition, several risk factors are identified. We analysed our data to determine the risk factors for postoperative deterioration of the creatinine clearance of 10% or more. Methods: All patients undergoing isolated coronary surgery in a single centre between January 1998 and December 2007 are included. Clinical data, including demographics and renal risk factors, were prospectively collected in our database. The most recent preoperative serum creatinine level and the maximum serum creatinine level within the first week postoperatively were used to calculate the creatinine clearance. A deterioration of 10% or more was considered to be an endpoint for this study. Results: In 10 098 out of a total of 10 626 patients, the preoperative as well as the postoperative creatinine clearance could be calculated. In 1053 patients, the deterioration of the creatinine clearance was 10% or more. We could identify the following risk factors: advanced age, diabetes, chronic obstructive pulmonary disease, peripheral vascular disease, emergency operation, previous cardiac surgery, low preoperative haemoglobin level, high preoperative C-reactive protein level, perioperative myocardial infarction, re-exploration and the number of blood transfusions. Conclusions: Risk factors for the deterioration of renal function after revascularisation have been confirmed in this study. In addition, we found peripheral vascular disease, previous cardiac surgery, low preoperative haemoglobin, increased preoperative C-reactive protein level, perioperative myocardial infarction and the number of blood transfusions to be risk factors that have not been described earlier

Preoperative renal function as a predictor of survival after coronary artery bypass grafting: Comparison with a matched general population

Objective: Preoperative renal dysfunction is an established risk factor for early and late mortality after revascularization. We studied how renal function affects long-term survival of patients after coronary artery bypass grafting. Methods: Early and late mortality were determined retrospectively among consecutive patients having isolated coronary bypass at a single Dutch institution between January 1998 and December 2007. Patients were stratified into 4 groups according to preoperative renal function. Expected survival was gauged using a general Dutch population group that was obtained from the database of the Dutch Central Bureau for Statistics; for each of our renal function groups, a general population group was assembled by matching for age, gender, and year of operation. Results: After excluding 122 patients lost to follow-up, 10,626 patients were studied; in 10,359, preoperative creatinine clearance could be calculated. Multivariate logistic regression and Cox regression analysis identified renal dysfunction as a predictor for early and late mortality. When long-term survival of patient groups was compared with expected survival, only patients with a creatinine clearance less than 30 mL · min-1 showed a worse outcome. Patients with a creatinine clearance between 60 and 90 mL · min-1 had a long-term survival exceeding the expected survival. Conclusions: Severity of renal dysfunction was related to poor survival. When compared with expected survival, however, patients having coronary bypass had a worse outcome only when severe preoperative renal dysfunction was present

Preoperative hemoglobin level as a predictor of survival after coronary artery bypass grafting: A comparison with the matched general population

BACKGROUND-: The predictive value of the preoperative hemoglobin value after coronary artery bypass grafting (CABG) has not been well established. We studied how the preoperative hemoglobin level affects the survival of patients after CABG. Late mortality was compared with that of a general population. METHODS AND RESULTS-: Early and late mortality of all consecutive patients undergoing isolated CABG between January 1998 and December 2007 were determined. Patients were classified into 4 groups stratified by preoperative hemoglobin level. The cutoff point for anemia was 13 g/dL for men and 12 g/dL for women. Expected survival of a matched general Dutch population cohort was obtained from the database of the Dutch Central Bureau for Statistics. After the exclusion of 122 patients who were lost to follow-up and 481 patients with missing preoperative hemoglobin levels, complete data were obtained in 10 025 patients. Multivariate logistic regression analyses revealed anemia to be an independent risk factor for higher early mortality. Cox regression analyses revealed low hemoglobin level, both as a continuous variable and as a dichotomous variable (anemia), to be a predictor of higher late mortality. Compared with expected survival, patients with the lowest preoperative hemoglobin levels had a worse outcome, whereas patients with the highest hemoglobin levels had a better outcome. CONCLUSIONS-: A lower preoperative hemoglobin level is an independent predictor of late mortality in patients undergoing CABG, whereas anemia is a risk factor for early and late mortality. Compared with the general population, anemic patients had worse survival than expected, whereas nonanemic patients had better survival than expected

Preoperative Atrial Fibrillation and Elevated C-Reactive Protein Levels as Predictors of Mediastinitis After Coronary Artery Bypass Grafting

Background: Mediastinitis is a serious complication after coronary artery bypass grafting (CABG). We studied the risk factors for the development of postoperative mediastinitis in a large group of patients who underwent isolated CABG at Catharina Hospital, Eindhoven, The Netherlands. Methods: Data of all patients undergoing an isolated CABG between January 1998 and December 2008 were analyzed. Univariate and multivariate logistic regression analyses were performed to investigate the effect of biomedical variables on the development of mediastinitis. Multivariate analyses were used to test for the confounding effect of various risk factors on outcomes. Results: Mediastinitis was present in 100 out of the 11,748 patients. Preoperative atrial fibrillation [odds ratio = 4.26 (2.26 to 8.02)] and an elevated preoperative C-reactive protein level [odds ratio = 1.013 (1.007 to 1.020)] were important independent predictors of the development of mediastinitis. Other significant risk factors were the following: age, chronic obstructive pulmonary disease, diabetes, morbid obesity, use of extracorporeal circulation, use of bilateral internal mammary arteries, reexploration for ischemia, and perioperative myocardial infarction. Conclusions: Apart from previously described risk factors for the development of postoperative mediastinitis, we found preoperative atrial fibrillation and an elevated C-reactive protein level to be significant predictors of mediastinitis in patients undergoing CABG

Effect of Body Mass Index on Early and Late Mortality After Coronary Artery Bypass Grafting

Background: The effect of obesity on the long-term outcome after coronary artery bypass graft surgery (CABG) remains controversial. We analyzed data of patients undergoing CABG in a single center, to determine the predictive value of body mass index in combination with comorbidities on early and late mortality. Methods: Early and late mortality of consecutive patients undergoing isolated CABG from January 1998 until December 2007 were determined. Patients were classified into five groups according to preoperative body mass index: underweight, normal weight, overweight, obese, and morbidly obese. Results: After excluding 122 patients who were lost to follow-up and 236 patients with missing preoperative body mass index, 10,268 patients were studied. Multivariate logistic regression analyses showed that underweight was associated with higher early mortality (hazard ratio 2.63; 95% confidence interval: 1.13 to 6.11, p = 0.025). Multivariate Cox regression analyses did reveal morbid obesity as an independent predictor of late mortality (hazard ratio 1.67, 95% confidence interval: 1.15 to 2.43, p = 0.007). Conclusions: Among patients undergoing isolated CABG, underweight is an independent predictor for early mortality, and morbid obesity is an independent predictor for late mortality

Transfusion of red blood cells: The impact on short-term and long-term survival after coronary artery bypass grafting, a ten-year follow-up

Transfusion of red blood cells (RBC) and other blood products in patients undergoing coronary artery bypass grafting (CABG) is associated with increased mortality and morbidity. We retrospectively analyzed data of patients who underwent an isolated coronary bypass graft operation between January 1998 and December 2007. Mean follow-up was 1696±1026 days, with exclusion of 122 patients lost to followup and 80 patients who received 10 units of RBC. Of the remaining patients, 8001 (76.7%) received no RBC, 1621 (15.2%) received 1-2 units of RBC, 593 (5.7%) received 3-5 units and 220 (2.1%) received 6-10 units. The number of transfused RBC was a predictor for early but not for late mortality. When compared to expected survival, survival of patients not receiving any blood product was better, while survival of patients receiving >3 units of RBC was worse. Transfusion of RBC is an independent, dose-dependent risk factor for early mortality after revascularization. Compared to expected survival, receiving no RBC improves patient long-term survival, whereas receiving three or more units of RBC significantly decreases patient survival

Diabetes and survival after coronary artery bypass grafting: comparison with an age- and sex-matched population

Objective: Long-term outcome after coronary artery bypass grafting is worse in diabetic than in non-diabetic patients. No data are currently available regarding survival rates of diabetic and non-diabetic patients after coronary revascularisation compared with cohorts from the general population in the Netherlands, which were matched for age and sex (normal Dutch survival). Methods: We retrospectively analysed the data from 10 626 patients who underwent coronary artery bypass grafting between January 1998 and December 2007. Of these, 8287 patients were non-diabetic, 1587 were non-insulin-dependent and 630 were insulin-dependent diabetic patients (122 patients were lost to follow-up). Survival of these patient groups was compared with the normal Dutch survival. Results: Multivariate analyses revealed non-insulin-dependent diabetes to be a risk factor for early mortality and both insulin-dependent and non-insulin-dependent diabetes as risk factors for late mortality. The 1-, 5- and 10-year survival rates for non-diabetic patients were 94.1% ± 0.3%, 86.8% ± 0.4% and 75.1% ± 1.7%, respectively, which was better than the normal Dutch survival. For insulin-dependent diabetic patients, 1-, 5- and 10-year survival rates were 90.3% ± 1.2%, 78.0% ± 2.0% and 60.5% ± 4.6%, respectively, and for non-insulin-dependent diabetic patients 91.4% ± 0.7%, 79.0% ± 1.3% and 58.9% ± 3.4%, respectively, which was worse than the normal Dutch survival. Conclusions: Non-insulin-dependent diabetes was a risk factor for early mortality and both types of diabetes were risk factors for late mortality after revascularisation. Compared with age- and sex-matched cohorts from the general Dutch population, the 10-year survival of non-diabetic patients was better; whereas the survival of both types of diabetic patients was worse