Risk stratification analysis of operative mortality in coronary artery bypass surgery

OBJECTIVE: We assessed the operative mortality of coronary artery bypass grafting (CABG) surgery using risk stratification. METHODS: In 294 consecutive patients who underwent CABG with or without concomitant surgery from August 1994 to December 1999, we compared operative mortality calculated conventionally and by risk stratification. Scores for each patient were calculated using the Parsonnet additive model and stratified based on the probability of operative mortality. RESULTS: Overall crude hospital mortality was 4.8%-4.0% among patients younger than 80 years and 14% among those 80 years of age or older (p = 0.0692). Hospital mortality was 12% in urgent/emergency surgery, and 1.5% in elective surgery (p < 0.0002), and 4.5% in CABG alone and 7.4% in CABG with concomitant surgery (p = 0.3763), and 25% in patients receiving vein grafts only and 3.0% in those receiving at least 1 artery graft (p = 0.0003). Overall patient distribution was 32% good, 20% fair, 20% poor, 11% high-risk, and 16% extremely high-risk. Predicted mortality was 2.2% for patients who were a good risk, 6.7% for fair-risk, 12% for poor-risk, 16% for high-risk, and 25% for extremely high-risk patients. Actual operative mortality was 1.0% for good-risk, 0% for fair-risk, 3.4% for poor-risk, 6.3% for high-risk, and 18% for extremely high-risk patients, making actual mortality significantly lower than that predicted. CONCLUSION: Comparing predicted mortality and actual mortality enabled us to objectively calculate operative results and assess operative quality.     

Factors affecting postoperative morbidity and mortality in isolated coronary artery bypass graft surgery

Purpose  This study was conducted to investigate predictors of mortality before and after isolated coronary artery bypass grafting (CABG). Methods  Single-institutional data on risk factors and mortality were collected for 8890 patients who underwent isolated CABG by the same group of surgeons. The relationship between risk factors and outcome was assessed using univariate and multivariate analyses in two risk models: a preoperative model (model 1) and then a pre-, intra-, and postoperative model (model 2). Results  The mean age of the patients (25.4% women and 74.6% men) was 58.5 ± 9.7 years. Fifty-five (0.6%) patients died after surgery. Hypercholesterolemia was the most common comorbidity factor (61.1%), followed by hypertension, a smoking habit, recent myocardial infarction (MI) <21 days, and diabetes. Postoperative tamponade, graft occlusion, and MI (0.01%) were the least common complications. The patients spent 39.7 ± 33.9 h in the intensive care unit (ICU) postoperatively. Patients were followed up for a minimum of 30 days. The multivariate analysis of our preoperative risk model revealed that the best predictors of operative mortality were a history of diabetes, hypertension, previous CABG, the presence of angina, arrhythmia, Canadian Cardiovascular Society Classification (CCS) of grade III or IV, ejection fraction (EF) ≤30%, three-vessel disease, and left main disease. Conclusion  After surgery, and with the inclusion of all the pre-, intra-, and postoperative variables into model two, the following were revealed to be prognostic factors for in-hospital mortality: a history of diabetes, hypertension, the presence of angina, CCS grades III or IV, EF −30%, absence of internal mammary artery (IMA) use, prolonged cardiopulmonary bypass (CPB) time, and prolonged ICU stay.     

Grade of left main coronary artery stenosis does not influence long-term mortality after coronary artery bypass surgery

Objective. To assess if grade of left main coronary artery (LMCA) stenosis influences early or long-term mortality after coronary artery bypass grafting (CABG). Design. Among all 1 384 patients with LMCA stenosis at Karolinska Hospital, Stockholm, Sweden during 1990–1999, 131 deaths occurred within 5 years of surgery (cases). Matched controls (n=146) were randomly selected from all surviving LMCA patients taking gender, age and year of surgery into account. Angiographies were classified for grade of LMCA stenosis before the operation. Results. High-grade LMCA stenosis was equally common among cases and controls (50 vs. 45%). The odds ratio (OR) of mortality 5 years after the operation in patients with high-grade versus low-grade LMCA stenosis based on the matched pairs was 1.2 (95% confidence interval (CI) 0.7–2.0) and after multivariable adjustment using information on all subjects the OR was 1.0 (95% CI 0.6–1.7). For early and one year mortality similar odds ratios were observed but with wide confidence intervals. Conclusions. Grade of LMCA stenosis does not appear to influence early or long-term mortality after CABG performed during 1990–1999.     

Anaesthesia for off-pump coronary artery bypass grafting

Achieving surgical revascularization of the heart, while avoiding the insult of cardiopulmonary bypass, is particularly desirable in specific high-risk patient groups. The relatively recent advances in surgical technique allowing high-quality grafting without mechanical arrest have led to an increase in popularity of off-pump coronary artery bypass surgery. Nonetheless, operating on the beating heart, manipulating it and purposely inducing ischaemia, invariably has significant haemodynamic consequences which must be carefully yet aggressively managed. To compound the situation, the intraoperative monitoring typically employed to evaluate cardiac function, such as electrocardiography and echocardiography, are of limited efficacy at crucial moments in the procedure. It is therefore essential that the anaesthetist is able to assimilate information from a multitude of sources in order to safely navigate the patient through a period of continually changing cardiovascular stress.     

Anaesthesia for off-pump coronary artery bypass grafting

Achieving surgical revascularization of the heart, while avoiding the insult of cardiopulmonary bypass, is particularly desirable in specific high-risk patient groups. The relatively recent advances in surgical technique allowing high-quality grafting without mechanical arrest have led to an increase in popularity of off-pump coronary artery bypass surgery. Nonetheless, operating on the beating heart, manipulating it and purposely inducing ischaemia, invariably has significant haemodynamic consequences which must be carefully yet aggressively managed. To compound the situation, the intraoperative monitoring typically employed to evaluate cardiac function, such as electrocardiography and echocardiography, are of limited efficacy at crucial moments in the procedure. It is therefore essential that the anaesthetist is able to assimilate information from a multitude of sources in order to safely navigate the patient through a period of continually changing cardiovascular stress.     

Risks of coronary artery bypass surgery in dialysis-dependent patients--analysis of the 2001 National Inpatient Sample.

BACKGROUND: Dialysis patients have a high risk of cardiovascular death but may under-use coronary artery bypass grafting (CABG) because of the risk of peri-operative death. Whether operative mortality in dialysis patients has declined with contemporary techniques is uncertain. We undertook this study in order to compare peri-operative mortality in chronic dialysis (CD) and non-dialysis patients following CABG and to determine whether high levels of comorbidity in CD patients account for identified differences in operative risk. METHODS: This study is a retrospective analysis of the 2001 National Inpatient Sample, a stratified probability sample of over seven million admissions in 33 states. Administrative data and ICD-9CM codes were used to identify dialysis patients, comorbidities, procedures and operative outcomes. Multivariable logistic regression was used to adjust for confounding. RESULTS: In this study, 77 323 non-dialysis patients and 635 dialysis patients underwent CABG. In-hospital death occurred in 11.1% of dialysis patients compared to 3.4% of non-dialysis patients. Rates of stroke, sepsis and pneumonia were also increased in dialysis patients. After adjustment for other surgical risk factors, the odds of in-hospital death were 3.38 (2.54-4.50, P < 0.001) times higher in dialysis than non-dialysis patients. CONCLUSIONS: Operative mortality in dialysis patients remains high despite recent advances in CABG surgery and is not explained by the high rates of comorbidity in dialysis patients. Because there is a very high risk of cardiovascular death without intervention, CABG may nevertheless be a life-saving therapy in CD patients. Randomized trials are needed to better define the optimal role of CABG in dialysis patients.     

High mortality after coronary bypass surgery in patients with high-grade left main coronary artery stenosis

Objective. To determine mortality after coronary artery bypass grafting (CABG) in relation to degree of left main coronary artery (LMCA) obstruction. Design. All patients without LMCA stenosis (n=3370), with low-grade stenosis (n?=?261), high-grade stenosis (n?=?224) or total occlusion of the LMCA (n?=?15) were followed for ten years after CABG performed during 1970–1989. Results. Early mortality was 1.9% and 2.3%, respectively, if there was no or a low-grade LMCA stenosis vs. 6.3% if the stenosis was high-grade. Ten-year survival was 76% if no LMCA obstruction, 74% if low-grade stenosis and 64% if the stenosis was high-grade. Risk of early death (odds ratio 2.6, 95% CI 1.4–4.8) and mortality at ten years (relative risk 1.5, 95% CI 1.1–2.0) was higher in patients with high-grade stenosis than in those without LMCA stenosis. There was no increased long-term mortality in patients with low-grade stenosis or among the few patients with occlusion of the LMCA. Conclusions. High-grade LMCA stenosis was associated with a three-fold increased risk of early and fifty percent higher risk of late death than in patients without LMCA stenosis.     

Increased risk associated with combined carotid endarterectomy and coronary artery bypass graft surgery: a propensity-matched comparison with isolated coronary artery bypass graft surgery

OBJECTIVE: Risk associated with combined carotid endarterectomy and coronary artery bypass graft surgery (CEA/CABG) is controversial. The present study objective was to compare morbidity and mortality outcomes in well-matched patients who underwent combined CEA/CABG surgery with patients undergoing isolated CABG surgery with and without a history of a prior CEA. DESIGN: This investigation was designed as a retrospective case-controlled study using data from the Cardiothoracic Anesthesia Patient Registry in a single tertiary institution. The patient population consisted of 1,698 isolated CABG surgery patients with carotid artery stenosis >40%, 708 patients who underwent an isolated CABG surgery but had a history of a prior CEA, and 272 combined CEA/CABG surgery patients who underwent surgery from January 4, 1993, through June 30, 2003. Propensity modeling techniques were used to calculate a propensity score for each patient. Greedy matching resulted in 272 propensity-matched pairs of combined CEA/CABG and isolated CABG patients (primary analysis) and 241 propensity-matched pairs of combined CEA/CABG surgery and isolated CABG surgery with previous CEA patients (secondary analysis). A Fisher exact, chi-square, Wilcoxon rank sum, and Student t test were applied appropriately to compare the propensity-matched pairs. RESULTS: The distribution of covariates among the propensity-matched combined CEA/CABG and isolated CABG groups were similar. Among the propensity-matched pairs in the primary analysis, overall morbidity and mortality were higher in the combined CEA/CABG group compared with the CABG group alone (overall morbidity 15% v 8.8%, p = 0.025, and mortality 5.2% v 1.1%, p = 0.007, respectively). Median intensive care unit (ICU) length of stay was longer (47 v 31 hours, p = 0.004) and hospital length of stay was longer (12 v 9 days, p < 0.001) for the combined CEA/CABG surgery compared with isolated CABG surgery, respectively. Postoperative cardiac, neurologic, serious infection, and renal morbid events were similar between the 2 groups. In the secondary analysis, the rates of mortality, overall morbidity, and neurologic morbidity were similar between the groups, whereas the median ICU and hospital length of stay were significantly longer in the combined CEA/CABG group (47.6 v 39.8 hours, p = 0.025, and 12.0 v 9.0 days, p < 0.001, respectively). CONCLUSIONS: Increased mortality and overall morbidity outcomes were found in the combined CEA/CABG group when compared with well-matched isolated CABG patients, but similar when compared with well-matched isolated CABG patients with a history of previous CEA. Patients undergoing combined CEA/CABG procedures had significantly longer ICU and hospital lengths of stay compared with patients undergoing isolated CABG procedures.     

Early and late outcome after coronary artery bypass surgery in diabetic patients

Objective. To determine the impact of diabetes on outcome after coronary artery bypass surgery. Design. We matched 866 diabetic patients with non-diabetic controls in regards to gender, age, left ventricular ejection fraction, body mass index, presence of unstable angina and history of myocardial infarction, and day of surgery. The 30-d mortality and morbidity were evaluated with univariate analysis and survival and freedom from cardiac death were assessed with the Kaplan–Meier method. Results. Follow-up time was 69±37 months. The 30-d mortality was 2.0% in the diabetic group and 1.0% in the non-diabetic group (p=0.15). Postoperative morbidity did not differ between groups. Cumulative 5- and 10-year survival rates were 89 and 71% in diabetics and 94 and 84% in non-diabetics (p=0.001). During follow-up, there was no difference between groups in regards to repeat revascularization. Conclusions. The 30-d mortality was equally low in diabetic and non-diabetic patients with severe coronary artery disease. However, long-term survival was significantly lower in the diabetic group than in the non-diabetic group.     

Off-pump coronary artery bypass grafting: A single center experience

Background Coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB) is gaining popularity as an effective alternative to conventional CABG using cardiopulmonary bypass. With the advent of mechanical tissue stabilization systems and intra coronary shunts the technique of off-pump CABG (OPCAB) is now applicable to revascularize the patients with multi-vessel disease. Methods A total of 293 patients underwent surgical myocardial revascularization without cardiopulmonary bypass between July 1996 and October 2000 at our hospital. Of these, 245 patients received 2 or more grafts: two in 193 patients, 3 in 46 patients and 4 in 7 patients. A mechnical tissue stabilization system (CTS or Octopus II/III) was used in all patients. In majority of the patients intra coronary shunts were also used. A total of 550 distal anastomoses were made and the vessels grafted were LAD (n=245), diagonal (n=90), ramus intermedius (n=16), obtuse marginal branches (n=58), distal right coronary artery (n=88) and posterior descending artery (n=52). Results There was no incidence of perioperative myocardial infarction. Three patients had transient ST segment elevation postoperatively which was normalized in the first few hours. Hospital mortality was 0.4%. No patient needed reexploration for bleeding. No patient had neurological event or pulmonary problems. All these patients except one were discharged from the hospital between 6 and 9 days. Conclusion In selected patients multi vessel OPCAB is a safe and reproducible technique and the mechanical tissue stabilization systems have made the procedure less difficult to perform. Its usefulness is more pronounced in high risk patients with comorbidities and the patients who undergo this procedure are free from major complications.     

Current status of coronary artery surgery

After a decade of experience with direct coronary artery surgery, certain conclusions have been made regarding its benefits and indications. Conclusion one is that the operation is highly successful in eliminating or alleviating angina; two, it improves exercise tolerance, and three, it prolongs life in patients with significant left main coronary artery disease. The proper selection of patients and the current technique of operation are also presented. Presented at the 79th Annual Congress of the Japan Surgical Society, Sapparo, 1979 May.     

经腔镜采集桡动脉行冠状动脉旁路移植术患者的术后护理

总结21例经腔镜采集桡动脉行冠状动脉旁路移植术患者的术后护理经验。术后护理要点包括预防桥血管痉挛,控制心率和血压,做好容量管理、血气指标监测、抗栓治疗护理、手术切口护理及患肢康复护理。21例患者采集桡动脉的伤口均Ⅰ期愈合。随访11～26个月,无1例患者出现桥血管堵塞现象,均未发生心绞痛复发及心肌梗死。     

Off-pump versus on-pump coronary artery bypass surgery and postoperative pulmonary dysfunction

OBJECTIVE: To investigate how off-pump coronary artery bypass grafting (CABG) affects postoperative pulmonary function when compared with on-pump CABG. DESIGN: Prospective clinical study. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Adult patients (n = 39) undergoing elective coronary artery bypass surgery with or without cardiopulmonary bypass. INTERVENTIONS: Two groups of patients were compared: 19 consecutive patients undergoing off-pump CABG surgery and 20 consecutive patients undergoing conventional CABG surgery. MEASUREMENTS AND MAIN RESULTS: Pulmonary function tests (flow volume loops and lung volumes with plethysmography) were done preoperatively and 72 hours postoperatively. Arterial blood gases and PaO2/FIO2 were measured at various stages. Sequential chest x-rays were obtained and evaluated for pleural changes, pulmonary edema, and atelectasis. In both groups, PaO2/FIO2 ratios decreased progressively throughout the perioperative period, with no significant differences between the groups at any stage during the study. There was a significant decline in postoperative pulmonary function tests in both groups, but there was no difference between groups at 72 hours postoperatively. No differences were found in the time to extubation, atelectasis scores, or postoperative complications. CONCLUSIONS: Off-pump CABG does not confer major protection from postoperative pulmonary dysfunction compared with CABG surgery with CPB. Strategies for minimizing pulmonary impairment after CABG surgery should be directed to factors other than the use of CPB.     

Results and predictors of early and late outcomes of coronary artery bypass graft surgery in octogenarians

OBJECTIVES: The aim of this study was to investigate early and late outcomes of coronary artery bypass graft (CABG) surgery in a large cohort of octogenarian patients. The results were compared with 2 other age groups including septuagenarians and patients <70 years old. DESIGN: A retrospective study of consecutive patients undergoing CABG surgery using a computerized database based on the New York State Department of Health registry. Data collection was performed prospectively. Setting: A university hospital (single institution). PARTICIPANTS: Two thousand nine hundred eighty-five patients undergoing CABG surgery including 282 (9.4%) octogenarians, 852 (28.6%) septuagenarians, and 1851 (62%) patients younger than 70 years old. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patient characteristics, hospital mortality, morbidity, length of stay, and long-term survival were analyzed. Octogenarians were more likely female and presented significantly more often with comorbidities such as heart failure, an ejection fraction <30%, peripheral vascular disease, and aortic calcification. Crude hospital mortality was 4.6% (n = 13) in octogenarians compared with 2.2% (n = 19) in septuagenarians and 2.4% (n = 44) in patients <70 years old (p = 0.067). Respiratory failure and gastrointestinal complications occurred more frequently in octogenarians. The stroke rate was 1.6% and similar in the 3 age groups. In multivariate logistic regression analysis, age >80 years was not a predictor of hospital mortality. The length of stay was significantly higher in octogenarians compared with nonoctogenarians (16 +/- 24 days v 10 +/- 13 days, p < 0.001). Five-year survival was 63% +/- 4% in octogenarians and was similar to that of an age- and sex-matched general US population. CONCLUSIONS: Excellent results after CABG surgery can be expected in octogenarians, with a minimal increase in postoperative mortality and acceptable postoperative morbidity. Respiratory failure is the main postoperative complication in octogenarians. Recent advances in operative techniques and perioperative management have contributed in improving surgical outcome in these patients compared with historic reports.     

Robotically enhanced coronary artery bypass surgery

Robotically enhanced telemanipulation surgery is a rapidly developing technique which enables totally endoscopic cardiac surgery with utmost precision and perfection on both beating heart and arrested heart. Between December 2002 and September 2006, 268 patients underwent robotically enhanced coronary artery bypass surgery using the da Vinci telemanipulation system. Fourteen patients underwent total endoscopic coronary artery bypass surgery. Of these 12 were performed on a beating heart and 2 on an arrested heart. Two-hundred and fifty-four patients had endoscopic takedown of the internal mammary artery followed by minimally invasive direct coronary artery bypass in 193 patients and left anterolateral thoracotomy in 61 patients. The internal mammary artery mobilization time was 36 min (28–76 min) and the left internal mammary artery to left anterior descending artery anastomosis time ranged from 20 to 36 min for the totally endoscopic coronary artery bypass patients. The right internal mammary artery of one patient was anastomosed to diagonal artery totally endoscopically. The mean internal mammary artery flow by Doppler measurement in patients undergoing minimally invasive direct coronary artery bypass was 58 ml min⁻¹. Seven patients required conversion to median sternotomy and coronary bypass surgery on the beating heart. The mean intensive care unit stay was 1.2 days and the mean hospital stay 4.5 days. There was one in-hospital mortality. All 14 patients who underwent total endoscopic bypass surgery had coronary angiography 3 months later which showed 100% patency in 13 patients. One patient had 50% anastomotic narrowing for which coronary angioplasty was performed in the same sitting. By using telematic technology, a complete endoscopic anastomosis is possible in both single vessels and suitable double vessel disease patients. The use of robotics is now extended to achieve complete myocardial revascularization by harvesting both the internal mammary arteries and making a small thoracotomy for direct anastomosis also.     

Safe evolution towards routine off-pump coronary artery bypass: negotiating the learning curve

Objective: Off-pump coronary artery bypass (OPCAB) hopes to avoid morbidity associated with cardiopulmonary bypass, improving clinical outcomes. Yet its technical difficulty and unfamiliarity raise concern that adoption of OPCAB might be associated with poorer outcomes during each surgeon's ‘learning curve’. We examined trends in patient selection over time as a single surgeon's practice evolved to routine OPCAB. Methods: Between 10-1-96 and 12-31-01, 1479 consecutive patients had isolated coronary artery bypass grafting (CABG). Clinical data were gathered prospectively and reviewed retrospectively. Trends in adoption of OPCAB and clinical outcomes were examined. Results: There were 756 OPCAB and 723 CABG/cardiopulmonary bypass patients. The practice evolved from 90% conventional CABG to 93% OPCAB. An abrupt transition coincided with evolution of techniques to expose the obtuse marginal arteries, and improvements in suction-based coronary stabilizers. Mortality was 1.0% for the off-pump group and 2.1% for the on-pump group. Careful patient selection helped maintain acceptable outcomes during the ‘learning curve’. Patients with depressed left ventricular ejection fraction, left main disease, and complex three vessel disease were excluded from OPCAB until significant experience (>200 cases) was attained. Presently, all isolated coronary bypass cases are candidates for OPCAB except patients with ischemic ventricular arrhythmias, those in cardiac arrest, and those for whom previous left pneumonectomy or deep pectus excavatum prevent rightward mobilization of heart. Conclusions: Despite a significant learning curve, evolution to routine OPCAB can be achieved while maintaining good patient outcomes. The development of specialized techniques, coronary stabilizers, and apical suction devices allows the application of OPCAB to virtually all coronary bypass patients, as surgeon experience matures.     

Replacement therapy for coronary artery bypass surgery in patients with hemophilia A and B

There are only a few cases of patients with hemophilia A and B who have undergone coronary artery bypass surgery. High levels of replacement therapy with factor concentrate either with bolus or continuous infusion are usually required pre‐operatively and during the first post‐operative days in order to maintain the coagulation deficient factor levels greater than 80% of normal. Heparinization during cardiopulmonary bypass appears to be safe and intra‐operative blood salvage using cell saver techniques reduce the need for transfusions.     

冠状动脉硬化性心脏病合并左锁骨下动脉严重狭窄非体外循环下同期手术的临床经验

目的探讨非体外循环冠状动脉旁路移植同时主动脉-锁骨下动脉旁路治疗冠状动脉硬化性心脏病(冠心病)合并锁骨下动脉重度狭窄的手术方法及效果.方法2003年1月～2004年5月,我院治疗须行冠状动脉旁路移植术同时合并左锁骨下动脉近端重度狭窄3例,术中先行主动脉-锁骨下动脉旁路,左乳内动脉获得满意的流量后,再行非体外循环冠状动脉旁路移植.结果手术时间210～340 min,平均283 min,出血量570～1 630 ml,平均963 ml.游离左乳内动脉后量杯测流量均＜5 ml/min,主动脉-锁骨下动脉旁路后量杯测流量均＞50 ml/min,乳内动脉远端与前降支吻合后流量仪测流量12～27 ml/min,平均20 ml/min.术后临床症状缓解,未发现冠脉-锁骨下动脉窃血综合征.3例随访3～6个月,平均5个月,无心绞痛发作.结论非体外循环冠状动脉旁路移植同时主动脉-锁骨下动脉旁路手术是治疗冠心病合并锁骨下动脉重度狭窄简单而有效的方法.     

Coronary artery and graft spasm after off-pump coronary artery bypass grafting

We report a case of a 52-year-old man with severe coronary artery and graft spasm after triple-vessel off-pump coronary artery bypass grafting. Emergent coronary angiography was performed to identify the location and severity of the spasm. Intracoronary injections of several vasodilators failed to relieve the spasm. Observational treatments including intra-aortic balloon pump and inotropic drugs to increase coronary flow were performed until the spasm resolved. The patient recovered and was discharged. A follow-up coronary angiography revealed patent native coronary artery and bypass grafts without evidence of residual spasm.