Effect of off-pump coronary artery bypass graft surgery on postoperative acute kidney injury and mortality

OBJECTIVE: Risk of mortality after cardiac surgery is associated with severity of acute kidney injury. The aim of this study is to examine the effect of off-pump coronary artery bypass surgery on the risk of postoperative acute kidney injury and its association with mortality. DESIGN: Observational cohort study. SETTING: Tertiary care center. PATIENTS: Some 10,061 patients underwent coronary artery bypass surgery (1998-2002), of which 1,365 patients underwent off-pump surgery. INTERVENTIONS: Acute kidney injury was defined as either requirement of dialysis or >/=50% decline in postoperative glomerular filtration rate but not requiring dialysis. We compared on- and off-pump surgeries and used propensity score matching to examine the effect of off-pump surgery on acute kidney injury and mortality. MEASUREMENTS AND MAIN RESULTS: We found that 2.6% on-pump and 1.2% off-pump patients developed acute kidney injury requiring dialysis among the 2,370 matched subjects (relative risk, 2.06; 95% confidence interval [CI], 1.36-3.36); 5.0% of on-pump patients suffered a >/=50% decline in glomerular filtration rate compared with 2.5% in off-pump group (relative risk, 2.00; 95% CI, 1.48-2.82). The mortality rate in the matched cohort was 2.3% for on-pump group vs. 0.6% in off-pump group (relative risk, 3.88; 95% CI, 2.29-9.50). Among matched patients with acute kidney injury, the risk of mortality was 13.14 (95% CI, 8.43-30.50) in patients requiring dialysis and 9.33 (95% CI, 4.83-19.00) in those with >/=50% decline in glomerular filtration rate but not requiring dialysis. CONCLUSIONS: Off-pump surgery is associated with a lower risk of developing acute kidney injury (regardless of its definition). The risk of mortality is incremental with worsening degrees of acute kidney injury. Lower risk of acute kidney injury may be one of the factors that offer a survival advantage after off-pump surgery.     

Comparison of sleep and mood in patients after on-pump and off-pump coronary artery bypass surgery.

BACKGROUND: Off-pump coronary artery bypass surgical procedures have been advocated to reduce the adverse effects of cardiopulmonary bypass on the brain. OBJECTIVE: To examine differences in objective and subjective characteristics of sleep and mood disturbance between patients after on-pump and off-pump coronary artery bypass surgery. METHODS: In a secondary analysis of pooled data from 2 previous studies, sleep characteristics and mood disturbance on postoperative night 2 after transfer to the cardiac surgery step-down unit were compared in patients who had on-pump and off-pump cardiac surgery. The sample included 129 coronary artery bypass patients: 48 on-pump patients from one hospital and 81 off-pump patients from another hospital. Data were obtained with wrist actigraphs. Subjective characteristics of sleep were determined by using the Pittsburgh Sleep Quality Index and a sleep diary; mood disturbance was evaluated by using the short form of the Profile of Mood States. RESULTS: Off-pump surgery was associated with better objective sleep continuity (decreased percentage of wake time after sleep onset and fewer awakenings) but not longer sleep duration after controlling for age and sex. The 2 groups of patients did not differ overall in subjective sleep characteristics, mood disturbance, or preoperative sleep quality. CONCLUSION: Use of off-pump coronary artery bypass surgery may improve sleep continuity during the early postoperative period. Prospective longitudinal studies are needed to evaluate the potential long-term benefits of this procedure during the different phases of recovery.     

Clinical outcomes of on-pump coronary bypass using heparin-bonded circuits and reduced anti-coagulation compare favorably with off-pump approach

Coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), or off pump, has gained popularity by avoiding the postoperative morbidity related to the use of CPB. Previously, we have demonstrated that CABG done on pump using heparin-bonded cardiopulmonary bypass circuits (HBC) with a lower anti-coagulation protocol (LAP) attenuates these effects, reduces homologous blood product requirement, and improves clinical outcome when compared with conventional CPB circuits. Our purpose in this study was to compare off-pump CABG clinical outcomes to on-pump CABG using HBC with LAP. We retrospectively analysed preoperative and postoperative variables of all primary CABG (n=1214) performed at this institution from 1 January 1997 to 28 July 2000. These patients were divided into the on-pump (n=1152) and off-pump groups (n=62). HBC with LAP were used in all on-pump CABG cases. There was no statistical difference in preoperative comorbid risk factors except percentage of females (on pump, 30% vs. off pump, 44%; p=0.02) and body surface area (on pump, 1.94 +/- 0.25 ml vs. off pump, 1.85 +/- 0.22 ml; p=0.02). There was no difference in intraoperative and postoperative complications, risk-adjusted mortality, total blood product usage, or length of stay. The mean number of distal anastomoses performed was significantly different (on pump, 3.5 +/- 0.82 vs. off pump 1.8 +/- 0.82; p < 0.001). Despite similar preoperative risk factors, clinical outcomes and homologous blood requirements were not statistically different between the off-pump and on-pump groups. These endpoints should not be the only criteria to justify performing off-pump CABG.     

非体外循环冠状动脉旁路移植治疗高危冠心病的评价

背景：非体外与体外循环冠状动脉旁路移植是治疗冠状动脉粥样硬化性心脏病的外科学方法,但目前尚无二者对高危冠心病患者疗效比较的系统评价。目的：通过Meta分析评价非体外与体外循环冠状动脉旁路移植对高危冠心病患者围手术期的疗效和安全性差异。方法：计算机检索PubMed、EMbase、中国期刊全文数据库、中国生物医学文献数据库、维普数据库、万方数据库和CochraneLibrary（2012年第8期）,并辅以检索相关文献的参考文献,语种限制为中文和英文,检索时间为1993年1月至2012年6月。严格按照纳入和排除标准进行筛选研究。由2位评价员独立对纳入的研究进行质量评价与提取资料并交叉核对,最后将提取的资料用RevMan5.1软件进行数据处理与分析。结果与结论：共纳入16个研究包括2个随机对照试验与14个观察性研究;共6441例患者,其中非体外循环冠状动脉旁路移植组2948例患者,常规体外循环下冠状动脉旁路移植组3493例患者。Meta分析结果显示：非体外循环冠状动脉旁路移植与常规体外循环下冠状动脉旁路移植比较,在围手术期脑卒中、主动脉内球囊反搏使用、再发心肌梗死、呼吸功能不全与死亡率,呼吸机辅助时间、ICU时间、住院时间,输血量及术后引流量方面的差异均有显著性意义,而在房颤、急性肾功能损伤、伤口感染及二次开胸率方面的差异均无显著性意义。结果提示,在围手术期方面与常规体外循环下冠状动脉旁路移植相比,对高危冠心病患者采用非体外循环冠状动脉旁路移植是安全有效的,且具有创伤少,手术死亡率低,术后恢复快,术后并发症少的优点,但是由于纳入文献数量有限且大多为非随机对照试验,因此非体外循环冠状动脉旁路移植并不能取代常规体外循环下冠状动脉旁路移植,其具体疗效与中远期疗效需要进一步通过更高质量、大样本量、多中心的随机双盲对照试验研究及长期的观察才能得出肯定的结论。     

Effects of off-pump coronary artery bypass grafting on patient outcome.

BACKGROUND: Cardiopulmonary bypass (CPB) is associated with postoperative myocardial stunning, hypothermia, formation of microemboli, and systemic inflammatory response syndrome, all of which may prolong recovery from coronary artery bypass grafting (CABG) surgery. This study sought to compare outcomes in patients undergoing CABG off pump versus on pump. METHODS: Outcomes, including mortality and several morbidities, were reviewed in 1,623 on-pump patients and 683 off-pump patients. Morbidities assessed included postoperative bleeding, incidence of multiorgan dysfunction, and neurologic complications. Chi-square and t-test analysis were used to determine statistical significance. RESULTS: Mortality was 42% lower in the off-pump group than the on-pump group. Both critical care and total hospital length of stay were significantly shorter in the off-pump group. The incidence of postoperative bleeding requiring transfusion or a return to the operating room was reduced by 29% in the off-pump group and the incidence of multiorgan dysfunction was reduced by 31%. The off-pump patients also presented a significantly lower incidence of cerebral vascular accidents and seizures than on-pump patients. CONCLUSIONS: We conclude that there is an association between improved patient outcome and off-pump CABG surgery. The outcomes of this study show a statistically significant decrease in mortality, critical care length of stay, total hospital stay, incidence of bleeding requiring transfusion or return to the operating room, amount of blood transfused, incidence of multiorgan dysfunction, cerebral vascular accidents, and seizures in off-pump patients when compared with on-pump patients. Such results support the use of myocardial revascularization off pump as an alternative to CABG surgery on pump. CABG surgery off pump may allow a better postoperative clinical course in patients who are candidates for the procedure.     

Does off‐pump coronary artery bypass surgery reduce secretion of plasminogen activator inhibitor‐1?

Prior studies showed that postoperative increase in plasminogen activator inhibitor-1 (PAI-1) levels is associated with an increased risk of graft occlusion after coronary artery bypass surgery (CABG). This prospective study aimed to compare the changes of PAI-1 antigen levels after off-pump and on-pump CABG. Forty-four patients admitted for elective CABG were randomised to on-pump (n=22) or off-pump (n=22) surgery. Serum samples were collected for estimation of PAI-1 and tissue plasminogen activator (t-PA) antigen levels preoperatively and 2 h after the operation. The groups were similar in terms of age, weight, gender ratio and extent of coronary disease, left ventricular function and number of grafts per patient. Fibrinogen and t-PA levels increased postoperatively in both the groups when compared with baseline values. After operation, statistical analysis revealed that increase of PAI-1 values was higher in off-pump group (44.1+/-9.1 vs. 25.3+/-6.9) than on-pump group (37.2+/-5.5 vs. 27.3+/-7.8, p=0.002). This study shows that increase in PAI-1 antigen values in patients who undergo off-pump (beating heart) CABG is significantly higher than in those who undergo conventional CABG with cardiopulmonary bypass.     

Coronary surgery for acute coronary syndrome: which determinants of outcome remain?

BACKGROUND: The mortality risk associated with coronary artery bypass grafting (CABG) after acute myocardial infarction remains controversial. The objective of the present study was therefore to analyze the outcome and predictors of in-hospital mortality in patients (pts) referred to CABG with acute coronary syndrome (ACS). PATIENTS AND METHODS: Between January 2003 and May 2005, a total of 3,127 pts underwent primary isolated CABG at our institution, including 220 pts with ACS. Out of these, unstable angina pectoris was present in 88 pts (group I), 97 pts (group II) had non-ST-elevation infarction, whereas 35 pts (group III) had ST-elevation infarction. Clinical data, in-hospital morbidity and mortality were recorded and studied retrospectively. RESULTS: Overall in-hospital mortality was 6.4% (n = 14) in the complete cohort, being 2.2% in group I (n = 2), 9.2% in group II (n = 9) and 8.5% (n = 3) in group III (P < 0.05). Logistic regression and receiver operating characteristic analyses identified age, NYHA, ejection fraction < 45%, catecholamine support, cardiogenic shock, renal disease and the additive EuroSCORE > 10 (P < 0.0001) as significant predictors related to in-hospital mortality. The mean time from the onset of symptoms to revascularization differed significantly between survivors (5.1 +/- 2.7 h) and no survivors (11.4 +/- 3.2 h) (P < 0.0007) in the STEMI group. Preoperative cTnI did not provide any prognostic information. CONCLUSION: CABG in pts with ACS can be performed with good clinical results. The clinical outcome is particular depending on the different groups of ACS. Therefore an individual risk stratification of each pts in ACS is necessary. The time interval of 6 h seems to be crucial as prognostic variable in the STEMI-group.     

Off-pump cardiac surgery abolishes complement activation

BACKGROUND: This prospective randomized study compared the inflammatory response in patients undergoing elective on-pump and off-pump coronary artery bypass grafting. PATIENTS AND METHODS: Forty-four patients undergoing elective coronary artery bypass grafting were recruited with 22 patients randomized to on-pump heart surgery and 22 patients to off-pump coronary bypass surgery. Plasma levels of C3bc, the terminal SC5b-9 complement complex, myeloperoxidase, beta-thromboglobulin and prothrombin fragment F1 + 2 were measured before the operation, intraoperatively, at termination of the operation, and two hours post-operatively. RESULTS: Complement was markedly activated in the on-pump group as indicated by a significant increase in C3bc and SC5b-9 (p < 0.001 for both), whereas no complement activation was seen in the off-pump group (p = 0.001 between the groups). In contrast, both groups showed significant activation of neutrophils, platelets and coagulation, as indicated by an early increase in myeloperoxidase and a post-operative increase in beta-thromboglobulin and F1 + 2, respectively. Notably, there were no intergroup differences with regard to neutrophil and platelet activation, whereas coagulation activation was more pronounced in the off-pump group (p < 0.01). CONCLUSIONS: Off-pump surgery completely eliminated the heart-lung machine-induced complement activation. Neutrophils and platelets were equally activated in both groups, whereas coagulation was enhanced post-operatively in the off-pump group.     

CT血管造影分析体外循环与非体外循环冠状动脉旁路移植后的桥血管通畅率

背景:近年来,非体外循环冠状动脉旁路移植后桥血管通畅率是否与传统的体外循环冠状动脉旁路移植相同存在争议.目的:探讨体外循环与非体外循环冠状动脉旁路移植后桥血管时间通畅率的差异性.方法:选取同一操作者行体外循环冠状动脉旁路移植患者100例,按其临床特征及桥血管病变危险因素匹配抽取非体外循环冠状动脉旁路移植患者137例.采用64排多螺旋CT血管造影分析冠脉搭桥后1个月,1年,2年,3年,4年的桥血管通畅情况.结果与结论:共对641条桥血管进行评价,两组中左侧乳内动脉桥血管时间通畅率均高于大隐静脉桥,两组左侧乳内动脉桥和人隐静脉桥血管时间通畅率比较差异均无显著性意义.说明非体外循环与体外循环冠状动脉旁路移植后患者桥血管时间通畅率相似,对于某些适当的患者来说,非体外循环冠状动脉旁路移植不失为一个良好的选择.     

70例冠状动脉旁路移植术临床分析

目的 比较分析体外循环冠状动脉旁路移植术和非体外循环冠状动脉旁路移植术的临床效果.方法 回顾2002年1月-2009年2月间我院行冠状动脉旁路移植术70例的临床资料,依据术中采用不同的手术方式分为体外循环组和非体外循环组.并对两组患者的术后临床资料、术后并发症发生情况进行分析.结果 术后非体外循环组发生并发症1例,体外循环组6例;非体外循环组住院死亡1例,体外循环组死亡3例.结论 在多支病变中,非体外循环冠状动脉旁路移植术和体外循环冠状动脉旁路移植术在再血管化的应用上无差别;非体外循环冠状动脉旁路移植术后的死亡率和并发症发生率比体外循环冠状动脉旁路移植术患者低,但是合并瓣膜病或严重的3支血管病变、左主干病变、室壁瘤形成的患者更适宜行体外循环冠状动脉旁路移植术,非体外循环冠状动脉旁路移植术不能取代体外循环冠状动脉旁路移植术.     

Oxidative injury and antioxidants in coronary artery bypass graft surgery: off-pump CABG significantly reduces oxidative stress

BACKGROUND: Coronary artery bypass grafting (CABG) can now be performed with or without cardiopulmonary bypass. The former entails global ischemia followed by reperfusion after declamping, whereas the latter does not. In view of growing evidence that reperfusion is associated with oxidative stress, we studied the extent of oxidative stress and antioxidant status in patients undergoing on-pump and off-pump CABG to determine whether the latter significantly reduces oxidative stress. METHODS: Thirty patients were initially enrolled for the study. The inclusion criteria included patients with atherosclerotic triple vessel disease, undergoing elective CABG, with good LV function, no major risk factors for surgery, with all biochemical investigations within normal limits, having stable angina and no history of previous infarct. Patients with valvular heart disease, ventricular aneurysm, heart failure and poor left ventricular function were excluded. These were alternately posted for on-pump and off-pump CABG. Eight patients were excluded as they developed unforeseen complications during the surgery. Out of the remaining 22 patients, 13 underwent off-pump CABG and 9 underwent on-pump CABG. Five blood samples were collected; baseline, 5, 15, 60 min and 24 h after reperfusion. Samples were analyzed for thiobarbituric acid reactive substances (TBARS), glutathione (G-SH) and catalase (CAT). The results were compared with their preanaesthetic levels in both the groups and also with 20 age- and sex-matched normal healthy individuals. RESULTS: Lipid peroxidation was significantly increased after reperfusion in patients undergoing on-pump CABG, maximum increase (p<0.0001) was seen 1 h after reperfusion, whereas off-pump CABG reduces oxidative stress. The G-SH levels were significantly decreased after reperfusion in on-pump and off-pump CABG patients, maximum decrease (p<0.0001) was seen 5 min after reperfusion in on-pump CABG. The catalase activity was significantly increased after reperfusion in on-pump and off-pump CABG patients, maximum increase (p<0.0001) was seen 1 h after reperfusion in on-pump CABG. CONCLUSION: Significant increase in oxidative stress was seen in patients undergoing on-pump CABG, whereas oxidative stress was less in off-pump CABG patients. The G-SH levels were decreased and Catalase activity was increased significantly in both on-pump and off-pump CABG patients.     

Elevation of serum cerebral injury markers correlates with serum choline decline after coronary artery bypass grafting surgery.

The aims of this study were to determine circulating choline status and its relationship to circulating levels of S-100beta protein and neuron-specific enolase, biochemical markers of cerebral injury and cognitive decline, after coronary artery bypass grafting (CABG) surgery. Preoperatively, patients scheduled for off-pump or on-pump CABG surgery had serum concentrations of 12.0+/-0.2 and 11.7+/-0.4 micromol/L free choline and 2640+/-65 and 2675+/-115 micromol/L phospholipid-bound choline, respectively. Serum free and bound choline levels decreased by 22-37% or 34-47% and 16-36% or 31-38% at 48 h after off-pump or on-pump surgery, respectively. Serum S-100beta and neuron-specific enolase increased from preoperative values of 0.083+/-0.009 and 6.3+/-0.2 microg/L to 0.405+/-0.022 and 11.4+/-0.8 microg/L, respectively, at 0 h postoperatively and remained elevated for 48 h after off-pump surgery. Serum free and bound choline concentrations were inversely correlated with the concentrations of S-100beta (r=-0.798; p<0.001 and r=-0.734; p<0.001) and neuron-specific enolase (r=-0.840; p<0.001 and r=-0.728; p<0.001). In conclusion, CABG surgery induces a decline in serum free and phospholipid-bound choline concentrations. The decreased serum choline concentrations were inversely correlated with the elevated levels of circulating cerebral injury markers. Thus, a decline in circulating choline may be involved in postoperative cognitive decline.     

Correlation between inflammatory response and markers of neuronal damage in coronary revascularization with and without cardiopulmonary bypass

Off-pump coronary artery bypass graft (CABG) surgery may reduce the inflammatory response and the neuronal damage associated with conventional CABG on cardiopulmonary bypass. The purpose of this study was to explore the protective effect of off-pump surgery by assessing plasma inflammatory and neuronal injury markers. Forty-one patients with coronary artery disease undergoing elective CABG were examined: 21 on-pump (Group I) and 20 off-pump (Group II). The perioperative release of interleukin-2 receptor (IL-2r), IL-6, tumor necrosis factor-alpha, S-100 protein (S-100) and neuron-specific enolase (NSE) were measured. Postoperative peak values of NSE (p < 0.001) and S-100 (p < 0.05) were significantly lower in Group II. IL-6 showed significantly lower values in off-pump patients (p < 0.001). A significant correlation was found between NSE and IL-6 (p < 0.001). In conclusion, off-pump surgery reduces the inflammatory response as well as the perioperative release of neuronal damage markers. Correlation between inflammatory activation and neuronal markers may suggest a link between inflammation and release of markers of neuronal clinical and subclinical injury.     

脑钠肽和内皮素在冠状动脉旁路移植术中的变化及意义

目的 观察氨基末端B型脑钠肽(Nt-proBNP)和大内皮素(bigET)在冠状动脉旁路移植术(CABG)前后的变化及其对术后近期并发症的预测价值.方法 分析47例常规体外循环冠状动脉旁路移植术(CCABG)和43例非体外循环冠状动脉旁路移植术(OPCAB)患者术前和术后24 h Nt-proBNP、bigET水平变化,及其对术后近期并发症的预测因子.结果 ①术后24 h CCABG和OPCAB两组Nt-pro BNP和bigET均明显升高,CCABG组Nt-proBNP由术前(1 083.5±717.9)pmol/L升到术后24 h(1 579.2±719.7)pmol/L(t=-4.30,P＜0.01),bigET由术前(1.10±1.82)pmol/L升到术后24 h(1.68±1.73)pmol/L(t=-5.35,P＜0.01);OPCAB组Nt-proBNP由术前(999.6±843.6)pmol/L升到术后24 h(1 460.8±830.0)pmol/L(t=-4.20,P＜0.01),bigET由术前(1.35±1.65)pmol/L升到术后24 h(1.73±1.50)pmol/L(t=-2.46,P=0.018).②术前Nt-proBNP水平与左室射血分数(LVEF)呈负相关(r=-0.43,P＜0.001).③经单变量和多变量Logistic回归分析,LVEF[相对比值比(OR)=1.045,95%可信区间(CI)为0.999～1.092,P=0.050]、术后24 h Nt-proBNP(OR=0.990,95%CI为0.999～1.000,P=0.014)水平是术后心力衰竭、低心排、围手术期心肌梗死、死亡、脑梗死的独立预测因子.经受试者工作特征曲线(ROC)分析术后24 hNt-proBNP＞1 174.41 pmol/L时,曲线下面积为0.698,95%CI为0.585～0.811,P＜0.003,敏感性为88.9%,特异性为57.1%,可预测近期并发症.结论 CABG术后Nt-proBNP、bigET明显升高;LVEF、术后24 h Nt-proBNP水平可预测术后近期并发症的发生.     

高龄冠心病患者冠状动脉搭桥术

目的；总结高龄冠心病患者冠状动脉搭桥术的术式选择和围术期处理特点。方法：101例高龄冠心病患者，行体外循环下冠状动脉旁路移植术（CCABG组）45例，非体外循环下冠状动脉旁路移植术（OPCAB组）56例，搭桥数目1-5支，平均3．1支。结果：所有病例无死亡，在手术时间、输血量、术后正性肌力药物应用、辅助呼吸时间等指标上OPCAB组高龄患者均优于CCABG组。术后并发症14例，其中CCABG组8例（17．8％），包括低心排出量综合征2例，低氧血症5例，心律失常3例，脑梗塞2例。OPCAB组6例（10．7％），包括低氧血症5例，心律失常3例。结论；根据高龄冠心病患者的特点制定相应的手术方案、选择合适的术式以及恰当的围术期处理，可以有效地降低高龄冠心病患者的手术并发症和死亡率。     

体外与非体外循环冠脉搭桥术后血清肌钙蛋白I水平变化及临床意义探讨

目的：比较常规体外循环冠状动脉搭桥术和非体外循环冠脉搭桥术后血清肌钙蛋白Ⅰ水平变化，探讨两种术式心肌保护差别。方法：选择48例冠脉搭桥患者，其中体外循环冠状动脉搭桥术组24例，非体外循环冠脉搭桥术组24例，分析两组肌钙蛋白Ⅰ的血浆浓度变化。结果：两组术前临床资料无差别；体外循环冠状动脉搭桥术组术后观察期内血浆肌钙蛋白Ⅰ较非体外循环冠脉搭桥术组明显升高（P〈0．01）。结论：非体外循环冠脉搭桥术组心肌损伤低于体外循环冠状动脉搭桥术组。     

急性心肌梗死后非体外循环冠状动脉搭桥术临床研究

目的:探讨冠心病急性心肌梗死30 d内非体外循环冠状动脉搭桥手术的可行性和安全性。方法:回顾性分析130例急性心机梗死患者30 d内非体外循环冠状动脉搭桥术患者的临床资料,分析冠状动脉病变、冠状动脉搭桥支数、血液动力学参数、心肌损伤指标等因素的变化。结果:130例急性心机梗死患者30 d内非体外循环冠状动脉搭桥手术后死亡4例(3.1%),心力衰竭9例(6.9%),心律失常20例(15.4%)。结论:急性心肌梗死30 d内冠状动脉搭桥手术具有可行性和安全性,但术前肌钙蛋白I应尽量接近或达到正常,急性期手术其术后并发症发生率高于非急性期手术。     

Predictors of survival in unselected patients with acute myocardial infarction requiring continuous catecholamine support

BACKGROUND: Several predictors of survival have been described in selected subgroups of patients suffering from acute myocardial infarction. However, data on unselected patients with acute myocardial infarction and cardiogenic shock, including patients with out-of hospital cardiac arrest, are missing. We aimed to assess predictors of survival for an unselected cohort of patients representative of clinical practice who experienced acute myocardial infarction and required continuous catecholamine support for circulatory failure. METHODS: The study was performed at a 2000 bed university hospital. All consecutive patients admitted to our emergency department with acute myocardial infarction were prospectively enrolled in a clinical trial from 1993 to 2000. DESIGN: A retrospective cohort study was performed on patients with myocardial infarction requiring catecholamine support within the first 24 h. Primary endpoint was in-hospital mortality. RESULTS: The analysis was carried out on 262 patients, 189 men (72%), median age 65 years (IQR 53-73). Out-of-hospital cardiac arrest was reported in 47% (122/262). In-hospital mortality was 53% (138/262). Survivors as compared to non-survivors exhibited significant differences with respect to age (60 vs. 68 years, P<0.0001), systolic and diastolic blood pressure on admission (110 vs. 102 mmHg, P=0.01 and 64 vs. 58 mmHg, P=0.006, respectively), initial blood serum lactate (6.8 vs. 8.3, P=0.01), peak CKMB level (93 vs. 138 U/l, P=0.005), use of adrenaline (epinephrine) (38 vs. 68%, P<0.0001) and any attempt of revascularisation (76 vs. 63%, P=0.03). In a multivariate model younger age [OR 1.06 (CI 1.03-1.10), P<0.001], no use of adrenaline [OR 2.63 (CI 1.35-5.26) P=0.005] and lower peak CKMB [OR 1.01 (CI 1.01-1.01), P<0.0001] were independently associated with in-hospital survival. CONCLUSION: In unselected patients including CPR survivors with acute myocardial infarction requiring continuous catecholamine support, younger age, the absence of continuous adrenaline administration and a lower peak CKMB were independently associated with increased in-hospital survival.     

Altered protein metabolism following coronary artery bypass graft (CABG) surgery

The aim of the present study was to investigate the acute effect of CABG (coronary artery bypass graft) surgery on the rates of synthesis of muscle protein, the positive acute-phase protein fibrinogen and the negative acute-phase protein albumin. Synthesis rates of muscle protein, fibrinogen and albumin were measured simultaneously before and 4 h after the end of surgery from the incorporation of L-[(2)H(5)]phenylalanine (given at 43 mg/kg of body weight) in 12 patients undergoing CABG surgery. Surgery was performed either with the use of extracorporeal circulation with cardiopulmonary bypass (on-pump; n=5) or with the beating heart procedure without cardiopulmonary bypass (off-pump; n=7). Post-surgical muscle protein fractional synthesis rates were decreased by 36+/-6.5% compared with pre-surgical values (1.59+/-0.10 compared with 0.97+/-0.08%/day respectively; P<0.001). In contrast, the synthesis rates of both fibrinogen (36+/-4 compared with 100+/-11 mg.day(-1).kg(-1) of body weight; P<0.0001) and albumin (123+/-12 compared with 178+/-19 mg.day(-1).kg(-1) of body weight; P<0.001) were both significantly increased after surgery. No significant differences were found between surgery performed with or without cardiopulmonary bypass. In conclusion, the results demonstrate that CABG surgery has a profound effect on protein metabolism, with a differential response of protein synthesis in muscle and liver.     

Impact of prophylactic postoperative beta-blockade on post-cardiothoracic surgery length of stay and atrial fibrillation

BACKGROUND: Previous studies have shown that post-cardiothoracic surgery atrial fibrillation (AF) increases the risk of hospital length of stay (LOS), overall mortality, pulmonary edema, and need for a balloon pump. A meta-analysis of 2 previous trials showed a nonsignificant reduction in LOS with postoperative beta-blockers but only encompassed 1200 patients, with few valve surgery patients, and neither study used a hospital within the US. OBJECTIVE: To evaluate the impact of postoperative beta-blockers on LOS and AF. Secondary endpoints of overall mortality, pulmonary edema, and need for an intra-aortic balloon pump (IABP) were also evaluated between groups. METHODS: This was a prospective cohort evaluation of all patients undergoing cardiothoracic surgery at our institution between October 1999 and October 2003. Patients receiving prophylactic postoperative beta-blockers were matched (1:1) with patients not receiving prophylaxis for age >70 years, valvular surgery, history of AF, gender, and use of preoperative digoxin and beta-blockers. RESULTS: Patients (n = 1660) receiving postoperative beta-blockade had a reduction in LOS (mean +/- SD 10.22 +/- 11.38 vs 12.40 +/- 15.67; p = 0.001) and AF (23.5% vs 28.4%; p = 0.02). Mortality, pulmonary edema, and need for IABP were reduced by >50% (p < 0.001; p = 0.001; p < 0.001, respectively), while myocardial infarction and stroke were not significantly impacted. CONCLUSIONS: In this observational cohort study, prophylactic postoperative beta-blocker use was associated with shorter hospital LOS by an average of 2.2 days and a 17.3% lower incidence of AF. It may also be associated with reductions in overall mortality, pulmonary edema, and need for an IABP.