Composite arterial grafts versus conventional grafting for coronary artery bypass grafting

OBJECTIVES: Composite arterial grafts for coronary artery bypass grafting surgery allow complete arterial revascularization but are limited by the inflow of a single internal thoracic artery supplying all the grafted vessels. We reviewed the safety of composite arterial grafts using either bilateral internal thoracic arteries or a single internal thoracic artery and radial artery. METHODS: From January 1999 to July 2002, 402 consecutive patients receiving composite grafts only were compared to a control group of patients (n = 542) undergoing coronary artery bypass grafting with internal thoracic artery and saphenous veins operated upon by the same surgeons. Two different statistical approaches were used to compare groups in this retrospective analysis. First, propensity score analysis with greedy matching technique was used to match patients from each group. Second, a multivariate analysis was performed looking at a combined patient outcome of death, intra-aortic balloon counterpulsation utilization, myocardial infarction, stroke, and prolonged ventilation on all patients in both groups. RESULTS: After matching by propensity score, the major clinical outcomes in composite arterial (n = 249) and control (n = 249) groups were found to be similar. The in-hospital mortality in the composite group was 1.2% as compared with 0.4% in matched patients (P =.62). However, patients in the composite group were found to have a significantly longer pump time (P <.0001), longer clamp time (P <.0001), increased incidence of prolonged mechanical ventilation (12.8% vs 4.8%; P =.002), and higher incidence of combined morbidity outcome (13.6% vs 6.4%; P =.007) as compared with matched patients. Multivariable analysis showed that composite arterial grafting was an independent predictor of the combined morbidity outcome with an odds ratio of 2.1 (1.2-3.7). CONCLUSIONS: These findings suggest that composite arterial grafting may be associated with an increase in risk-adjusted patient morbidity when compared with a conventional coronary artery bypass grafting group, although a mortality difference was not demonstrable.     

中国冠状动脉旁路移植手术住院死亡危险因素分析

目的 分析影响中国冠状动脉旁路移植术(CABG)术后住院死亡的危险因素.方法 全国32家心脏外科中心2004-2005两年共行9247例CABG术.确定潜在危险因素后,根据潜在危险因素从临床资料中收集数据,最终数据分为生存组和住院死亡组,对影响住院死亡的潜在危险因素进行单因素分析和Logistic多因素回归分析,最终确立影响中国CABG住院死亡的危险因素,并对结果的校准度和分辨能力进行检验.结果 全组平均年龄(62.1 ±9.1)岁,女性占21.5%,冠脉三支病变占76.7%,左主干病变25.8%.总体住院病死率3.3%.Logistic多因素回归分析发现,年龄、肾衰史、慢性阻塞性肺疾病、既往心血管手术、不稳定型心绞痛、左心室射血分数、术前危重状态、非择期手术、合并其他手术为CABG住院死亡的独立危险因素.Hosnm-Lemeshow X2检验结果X2=2.987,P=0.935.受试者工作特征(ROC)曲线下面积为0.75.结论 通过Logistic多因素回归分析,得出年龄、肾衰史、慢性阻塞性肺疾病、既往心血管手术、不稳定型心绞痛、左心室射血分数、术前危重状态、非择期手术、合并其他手术等9个因素为影响中国病人CABG住院死亡的独立危险因素.分析结果具有良好的校准度和分辨能力.     

Off-pump coronary artery bypass grafting: not a flash in the pan

During the past decade, technical improvements have made off-pump coronary artery bypass operations a routine procedure. During this time, off-pump coronary artery bypass has been audited against conventional techniques by many observational, case-matched, and prospective randomized studies. There is evidence in the literature suggesting that off-pump coronary artery bypass operations reduce postoperative morbidity, organ dysfunction, and costs, without compromising midterm outcome compared with conventional coronary operations. The available evidence also supports the view that high-risk patients might benefit the most from revascularization on the beating heart. High quality follow-up data are still needed to assess the impact of off-pump coronary artery bypass operations on long-term clinical outcome.     

First-year outcomes of beating heart coronary artery bypass grafting using proximal mechanical connectors

BACKGROUND: To determine the extended results of mechanical connectors we compared the 1-year outcomes of patients having beating heart coronary artery bypass surgery with at least one sutured or mechanically connected proximal vein graft anastomosis. METHODS: From May 2001 to December 2001, 166 patients were identified as having undergone off-pump bypass grafting utilizing at least one St. Jude symmetry aortic connector (St Jude Medical Anastomotic Technology Group, St. Paul, MN). Follow-up for major adverse cardiac events (MACEs), which is defined as cardiac mortality, myocardial infarction, or revascularization of a previous target vessel, was obtained on 162 patients (97.6%). A control group of 159 patients was identified from a cohort of patients having beating heart surgery with one or more sutured proximal vein graft anastomosis in the preceding year. The MACE follow-ups were obtained in 136 patients (85.6%) by direct telephone contact. RESULTS: Patients with connectors showed an accelerated number of MACEs beginning approximately 180 days from the time of surgery and stabilizing at approximately 300 days. Logistic regression analysis identified the presence of diabetes as a significant preoperative risk factor predisposing patients to earlier onset of MACEs (p = 0.03) with an odds ratio of 2.9 (95% confidence interval, 1.1 to 7.6). Insulin dependent diabetics showed no differences between connector and control patients in the frequency or timing of MACEs. Connector patients using oral hypoglycemic agents demonstrated a significant deviation (p = 0.01) from a similar control population in the prevalence and timing of MACEs. CONCLUSIONS: Connector patients showed an increased incidence of early MACEs. These events were characterized by an increased requirement for early target vessel revascularization and were predominantly in noninsulin-dependent diabetics.     

Predictors of stroke in the modern era of coronary artery bypass grafting: a case control study

BACKGROUND: Stroke is a rare but devastating complication after coronary artery bypass grafting (CABG) and its prevention remains elusive. We used a case control design to investigate the extent to which preoperative and perioperative factors were associated with occurrence of stroke in a cohort of consecutive patients undergoing myocardial revascularization. METHODS: From April 1996 to March 2001, data from 4,077 patients undergoing CABG were prospectively entered into a database. The association of preoperative and perioperative factors with stroke was investigated by univariate analyses. Factors observed to be significantly associated with stroke in these analyses were further investigated using multiple logistic regression to estimate the strength of the associations with the occurrence of stroke, after taking account of the other factors. RESULTS: During the study period, 4,077 patients underwent CABG and of these 923 (22.6%) had off-pump surgery. Forty-five patients suffered a perioperative stroke (1.1%). Overall there were 46 in-hospital deaths (1.1%), of whom 6 also suffered a stroke. Brain imaging of the stroke patients showed embolic lesions in 58%, watershed in 28%, and mixed in 14%. Multivariate regression analysis identified several preoperative factors as independent predictors of stroke, ie, age, unstable angina, serum creatinine greater than 150 mcg/ml, previous cerebrovascular accident (CVA), peripheral vascular disease (PVD), and salvage operation. When operative risk factors were added to the adjusted model, off-pump surgery was associated with a substantial, but not significant, protective effect against stroke (odds ratio = 0.56, 95% confidence interval 0.20 to 1.55). Survival for stroke patients was 93% and 78% at 1 and 5 years, respectively. CONCLUSIONS: Overall incidence of stroke is relatively low in our series. Age, unstable angina, previous CVA, PVD, serum creatinine greater than 150 mcg/ml, and salvage operation are independent predictors of stroke. These factors should be taken into account when informing each individual patient on the possible risk of stroke and in the decision-making process on the surgical strategy.