Is preoperative serum creatinine a reliable indicator of outcome in patients undergoing coronary artery bypass surgery?

ObjectiveEvaluating renal function by calculating creatinine clearance as an alternative measure to serum creatinine may give a better estimation of postoperative renal function in patients undergoing coronary artery bypass grafting.MethodsUsing our database, we conducted a retrospective review of the records of all 11,884 patients aged 21 years or older undergoing pure bypass grafting who required cardiopulmonary bypass. Preoperative renal function was categorized as normal renal function (serum creatinine ≤1.1 mg/dL and creatinine clearance > 60 mL/min), occult renal insufficiency (serum creatinine ≤ 1.1 mg/dL and creatinine clearance ≤ 60 mL/min), mild renal insufficiency (1.1 mg/dL < serum creatinine ≤ 1.5 mg/dL and creatinine clearance ≤ 60 mL/min) or moderate renal insufficiency (serum creatinine > 1.5 mg/dL and creatinine clearance ≤ 60 mL/min).ResultsOut of 11,884 patients in the sample, 7856 (66.1%) had normal renal function, and 706 (5.9%) had occult renal insufficiency. The rate of postoperative mortality, renal failure, atrial fibrillation, prolonged ventilation, intra-aortic balloon pump usage, and prolonged hospital stay (>7 days) was higher in patients with occult renal insufficiency than in the normal group in univariable analysis. Multivariable logistic regression analysis demonstrated that patients with occult renal insufficiency compared with the group with normal renal function were at higher risk for mortality (odds ratio = 2.59, 95% confidence interval 1.15–5.86; P = .022) and prolonged hospital stay (>7 d) (odds ratio = 1.30, 95% confidence interval 1.08–1.57; P = .005).ConclusionsTo identify higher-risk patients requiring special intensive care, and in whom new interventions can be performed to improve outcome, we recommend the preoperative calculation of creatinine clearance, especially in older women with a lower body mass index

Serum Uric Acid Level and Metabolic Syndrome in Patients Undergoing Coronary Angiography

ABSTRACT Background and Objectives: The association between metabolic syndrome (MetS) and hyperuricemia has been formerly studied mostly in healthy people in western countries. We tried to examine the relationship between hyperuricemia and MetS in an Iranian population undergoing coronary angiography. Materials and Methods: From March 2008 to September 2008, we studied 465 patients (260 men, 55.9%) undergoing elective coronary angiography due to symptoms related to coronary artery disease. The MetS was defined according to the adapted Adult Treatment Panel III (ATP-III A), and hyperuricemia was defined as serum uric acid concentrations ≥ 7.0 mg/dl in men and ≥ 6.0 mg/dl in women. For the statistical analysis, the statistical software SPSS version 13.0 and the statistical package SAS version 9.1 were applied Results: The mean age of the study population was 59.66 ± 10.04, ranging from 31 to 85 years. Hyperuricemia was detected in 231 (49.7%) of total population, in 126 (54.5%) of men, and in 105 (45.5%) of women. In the multivariable adjusted model, subjects with MetS and subjects with 5 components of the MetS compared to those without any components of the MetS, had 1.56-fold and 4.19-fold increased odds of hyperuricemia, respectively. Hyperuricemia was significantly associated with elevated BP and low level of HDL-cholesterol but not with other components of MetS. Conclusions: Our study demonstrated that hyperuricemia was strongly associated with the prevalence of MetS according to adapted ATP III guidelines in an Iranian sample of patients undergoing coronary angiography

Effect of milrinone on short-term outcome of patients with myocardial dysfunction undergoing coronary artery bypass graft: A randomized controlled trial

Background: Myocardial dysfunction needing inotropic support is a typical complication after on-pump cardiac surgery. In this study, we evaluate the effect of milrinone on patients with ventricular dysfunction undergoing coronary artery bypass graft (CABG). Methods: Seventy patients with impaired left ventricular function [left ventricular ejection fraction (LVEF) < 35%] undergoing on-pump CABG were enrolled. Patients were randomized to receive either an intraoperative bolus of milrinone (50 &#956;g/kg) or saline as placebo followed by a 24-hour infusion of each agent (0.5 &#956;g/kg/min). Hemodynamic parameters and transthoracic echocardiographic measurement of systolic and diastolic functions were the variables evaluated. Results: Serum levels of creatine phosphokinase (CPK), the MB isoenzyme of creatine kinase (CK-MB), occurrence of myocardial ischemia or infarction, and mean duration of using inotropic agents were significantly lower in the milrinone group (p < 0.05). There were no significant differences between the two groups regarding the development of ventricular arrhythmia, duration of cardiopulmonary bypass, intra-aortic balloon pump and inotropic support requirement, duration of mechanical ventilation, duration of intensive care unit stay and mortality rate. Although mean pre-operative LVEF was significantly lower in the milrinone group, there was no significant difference between post-operative LVEFs. Conclusions: We suggest that perioperative administration of milrinone in patients undergoing on-pump CABG, especially those with low LVEF, is beneficial. (Cardiol J 2010; 17, 1: 73-78

Determinants of Length of Stay in Surgical Ward after Coronary Bypass Surgery: Glycosylated Hemoglobin as a Predictor in All Patients, Diabetic or Non-Diabetic

Background: Reports on the determinants of morbidity in coronary artery bypass graft surgery (CABG) have focused on outcome measures such as length of postoperative stay in the Intensive Care Unit (ICU). We proposed that major comorbidities in the ICU hampered the prognostic effect of other weaker but important preventable risk factors with effect on patients’ length of hospitalization. So we aimed at evaluating postoperative length of stay in the ICU and surgical ward separately. Methods: We studied isolated CABG candidates who were not dialysis dependent. Preoperative, operative, and postoperative variables as well as all classic risk factors of coronary artery disease were recorded. Using multivariate analysis, we determined the independent predictors of length of stay in the ICU and in the surgical ward. Results: Independent predictors of extended length of stay in the surgical ward ( > 3 days) were a history of peripheral vascular disease, total administered insulin during a 24-hour period after surgery, glycosylated hemoglobin (HbA1c), last fasting blood sugar of the patients before surgery, and inotropic usage after cardiopulmonary bypass. The area under the Receiver Operating Characteristic Curve (AUC) was found to be 0.71 and Hosmer-Lemeshow (HL) goodness of fit statistic p value was 0.88. Independent predictors of extended length of stay in the ICU ( > 48 hours) were surgeon category, New York Heart Association functional class, intra-aortic balloon pump, postoperative arrhythmias, total administered insulin during a 24-hour period after surgery, and mean base excess of the first 6 postoperative hours (AUC = 0.70, HL p value = 0.94 ). Conclusion: This study revealed that the indices of glycemic control were the most important predictors of length of stay in the ward after cardiac surgery in all patients, diabetic or non-diabetic. However, because HbA1c level did not change under the influence of perioperative events, it could be deemed a valuable measure in predicting outcome in CABG candidates

Monitoring of Anticoagulant Therapy in Heart Disease: Considerations for the Current Assays

Clinicians should be aware of new developments to familiarize themselves with pharmacokinetic and pharmacodynamic characteristics of new anticoagulant agents to appropriately and safely use them. For the moment, cardiologists and other clinicians also require to master currently available drugs, realizing the mechanism of action, side effects, and laboratory monitoring to measure their anticoagulant effects. Warfarin and heparin have narrow therapeutic window with high inter- and intra-patient variability, thereby the use of either drug needs careful laboratory monitoring and dose adjustment to ensure proper antithrombotic protection while minimizing the bleeding risk. The prothrombin time (PT) and the activated partial thromboplastin time (aPTT) are laboratory tests commonly used to monitor warfarin and heparin, respectively. These two tests depend highly on the combination of reagent and instrument utilized. Results for a single specimen tested in different laboratories are variable; this is mostly attributable to the specific reagents and to a much lesser degree to the instrument used. The PT stands alone as the single coagulation test that has undergone the most extensive attempt at assay standardization. The international normalized ratio (INR) was introduced to ‘‘normalize’’ all PT reagents to a World Health Organization (WHO) reference thromboplastin preparation standard, such that a PT measured anywhere in the world would result in an INR value similar to that which would have been achieved had the WHO reference thromboplastin been utilized. However, INRs are reproducible between laboratories for only those patients who are stably anticoagulated with vitamin K antagonists (VKAs) (i.e., at least 6 weeks of VKA therapy), and are not reliable or reproducible between laboratories for patients for whom VKA therapy has recently been started or any other clinical conditions associated with a prolonged PT such as liver disease, disseminated intravascular coagulation, and congenital factor deficiencies. In contrast to marked progress in the standardization of PT reagents for INR reporting, no standardization system has been globally adopted for standardization of PTT reagents. Recently College of American Pathologists recommend that individual laboratories establish their own therapeutic range by using aPTT values calibrated against accepted therapeutic unfractionated heparin (UFH) levels calibrated against accepted therapeutic UFH levels performing anti-Xa test (which is the most accurate assay for monitoring UFH therapy).Herein, we review recent data on the monitoring of conventional anticoagulant agents. Marked interlaboratory variability still exists for PT, INR, and PTT tests. Further research should be focused on improving the standardization and calibration of these assays

Carotid Artery Stenting, Endarterectomy, or Medical Treatment Alone: The Debate Is Not Over

The management of carotid artery stenosis reduces the risk of stroke and its related deaths. Management options include risk factor modification and medical therapy, carotid endarterectomy (CEA), and carotid artery stenting (CAS). Although several randomized controlled trials (RCTs), mostly conducted in late-1980s and mid-1990s, have proved CEA to be effective in the prevention of ipsilateral ischemic events in selected patients with carotid artery stenosis, aggressive risk factor modification and medical therapy with recently introduced antiplatelet agents, statins, and more effective antihypertensive medications may have reduced compelling indications for immediate surgery in asymptomatic populations. Also recently, due to improvements in percutaneous techniques and carotid stents, CAS has received wide attention as a potential alternative to CEA. Herein, we review the recent data on the management options of carotid artery stenosis and seek to identify the most appropriate treatment strategy in selected patients with carotid artery stenosis

Role of Surgeon in Length of Stay in ICU after Cardiac Bypass Surgery

Background: We presumed that the surgeon himself has an impact on the results after coronary artery bypass grafting (CABG) as there is no unique protocol for the discharge of post-operative cardiac patients at our institution. Therefore, we examined whether the surgeon himself has an impact on the intensive care unit (ICU) stay of isolated CABG patients.Methods: We prospectively studied a total of 570 consecutive patients undergoing elective CABG. Length of stay in the ICU was defined as the number of days in the ICU unit post-operatively. Seven operating surgeons were classified in 3 categorieson the basis of the mean hospital stay of their patients (1, 2 and 3 if the mean total patients' stay in hospital was <8 days,between 8 to 10 days, and longer than 10 days; respectively). Using a multivariable regression model, we determined the independent predictors of length of stay in the ICU (> 48 hours) and examined the role of surgeon in this regard.Results: Incidence of post-operative arrhythmia and length of ICU stay were higher in the patients of surgeon category 3 than those of surgeon categories 1 and 2. Surgeon category 3 also operated on patients with higher EuroSCOREs than did surgeon categories 1 and 2. With the aid of a multivariable stepwise analysis, three variables were identified as independent predictors significantly associated with ICU length of stay: age, history of cerebrovascular accident, and surgeon category.Conclusion: Surgeon category may independently predict a prolonged length of stay in the ICU. We suggest that a unique discharge protocol for post-CABG patients be considered to restrict the role of surgeon in the ICU stay of these patients

Frequency and Predictors of Renal Artery Stenosis in Patients Undergoing Simultaneous Coronary and Renal Catheterization

Background: Atherosclerotic renal artery stenosis (ARAS) remains underdiagnosed due to its nonspecific demonstrations. We aimed to both estimate the frequency of ARAS in high-risk non-selected patients undergoing simultaneous coronary and renal catheterization and possibly identify a predictive model for ARAS using baseline clinical, laboratory, and coronary angiographic variables. Methods: The records of 866 patients aged ≥ 21 years undergoing simultaneous coronary and renal angiography were retrieved for analysis from our computerized database. The degree of ARAS was estimated visually by experienced attending interventional cardiologists. Lesions with an estimated stenosis of ≥ 50% were considered significant. Multivariable stepwise logistic regression models were used to identify the risk factors predicting the presence and extent of ARAS. Results:  Of a total of 866 consecutive patients undergoing renal angiography in conjunction with coronary angiography (mean age ± SD: 63.06 ± 10.32, ranging from 24 to 89 years), 454 (57%) were men. A total of 345 (39.8%) cases had significant ARAS, 77 (22.3%) of which were bilateral. Using significant ARAS as the dependent variable, six variables were identified as the independent predictors significantly associated with the presence of ARAS, namely age, female sex (male sex was found to be a protector), hypertension, history of renal failure, left anterior descending artery (LAD) stenosis > 50%, and left circumflex artery (LCX) stenosis > 50%. The Gensini score was not found to be a predictor of the presence of ARAS, but it was more likely associated with a trend towards a more extensive ARAS (adjusted OR = 1.00, 95% CI = 1.00-1.01; p value = 0.039). Other independent determinants of the ARAS extent were the same as the predictors of the ARAS presence. Conclusions: Although risk versus benefit was not tested in this study, it seems that clinicians could consider renal catheterization in combination with coronary angiography particularly in female patients with advanced age and with significant coronary artery stenoses in the LAD and LCX