Effect of clopidogrel premedication in off-pump cardiac surgery: are we forfeiting the benefits of reduced hemorrhagic sequelae?

BACKGROUND: Premedication with clopidogrel has reduced thrombotic complications after percutaneous coronary revascularization procedures. However, because of the enhanced and irreversible platelet inhibition by clopidogrel, patients requiring surgical revascularization have a higher risk of bleeding complications and transfusion requirements. A principal benefit of surgical coronary revascularization without cardiopulmonary bypass is its lower hemorrhagic sequelae. The purpose of this study was to evaluate the effect of preoperative clopidogrel administration in the incidence of hemostatic reexploration, blood product transfusion rates, morbidity, and mortality in patients undergoing off-pump coronary artery bypass graft surgery using a large patient sample and a risk-adjusted approach. METHODS AND RESULTS: Two hundred eighty-one patients (17.9%) did and 1291 (82.1%) did not receive clopidogrel before their surgery, for a total of 1572 patients undergoing isolated off-pump coronary artery bypass graft surgery between January 2000 and June 2002. Risk-adjusted logistic regression analyses and a matched pair analyses by propensity scores were used to assess the association between clopidogrel administration and reoperation as a result of bleeding, intraoperative and postoperative blood transfusions received, and the need for multiple transfusions. Hemorrhage-related preoperative risk factors identified in the literature and those found significant in a univariate model were used. The clopidogrel group had a higher likelihood of hemostatic reoperations (odds ratio [OR], 5.1; 95% confidence interval [CI], 2.47 to 10.47; P<0.01) and an increased need in overall packed red blood cell (OR, 2.6; 95% CI, 1.94 to 3.60; P<0.01), multiple unit (OR, 1.6; 95% CI, 1.07 to 2.48; P=0.02), and platelet (OR, 2.5; 95% CI, 1.77 to 3.66; P<0.01) transfusions. Surgical outcomes and operative mortality (1.4% versus 1.4%; P=1.00) were not statistically different. CONCLUSIONS: Clopidogrel administration in the cardiology suite increases the risk for hemostatic reoperation and the requirements for blood product transfusions during and after off-pump coronary artery bypass graft surgery.

Contemporary performance of surgical ventricular restoration procedures: data from the Society of Thoracic Surgeons' National Cardiac Database.

BACKGROUND: Surgical ventricular restoration (SVR) is an operation that demonstrates promise to improve outcomes for patients with left ventricular dysfunction. Current use and operative outcomes of SVR have come from centers of expertise, and operative risks of SVR in community practice are unknown. We sought to characterize the performance of SVR nationally and describe the acute risks of mortality and major morbidity plus predictors of adverse outcomes. METHODS: We identified patients undergoing an SVR procedure at US hospitals participating in the Society of Thoracic Surgeons (STS) National Cardiac Database from January 2002 to June 2004. Baseline characteristics, operative characteristics, clinical outcomes, and predictors of adverse procedural outcomes were analyzed. RESULTS: There were 731 patients who underwent SVR at 141 of STS's 576 hospitals, and 20 centers performed 10 SVR procedures or more. The operative mortality was 9.3%; reoperation in 14.1%, stroke in 3.3%, renal failure in 8.1%, and prolonged ventilation in 21.5%. Combined death or major complications occurred in 33.5%. Major predictors of this combined end point were age, female sex, creatinine > or = 2 mg/dL, insulin-dependent diabetes, myocardial infarction within 1 week, history of congestive heart failure, 3-vessel coronary disease, severe mitral insufficiency, and status of surgery. CONCLUSION: This study provides a first look at use and outcomes of SVR in a national sample. Although a quarter of STS sites are performing SVR, most have limited experience and perioperative events are somewhat higher than prior selected series. Further studies of SVR are needed to improve patient selection and procedural performance.

Chronologic distribution of stroke after minimally invasive versus conventional coronary artery bypass.

OBJECTIVES: We sought to investigate whether the chronologic distribution of the onset of stroke occurring after coronary artery bypass graft surgery (CABG) without cardiopulmonary bypass (off-pump CABG) is different from the conventional on-pump approach (CABG with cardiopulmonary bypass). BACKGROUND: Off-pump CABG has been associated with a lower stroke rate, compared with conventional on-pump CABG. However, it is unknown whether the chronologic distribution of the onset of stroke is different between the two approaches. METHODS: We evaluated the chronologic distribution of postoperative stroke in patients undergoing CABG from June 1996 to August 2001 (n = 10,573). Preoperative risk factors for stroke were identified using the Northern New England preoperative estimate of stroke risk. Multivariate logistic regression analysis was used to determine the independent predictors of early stroke and to delineate the association between the surgical approach and the chronologic distribution of the onset of stroke. RESULTS: Stroke occurred in 217 patients (2%, n = 10,573). A total of 44 (20%) and 173 (80%) of these patients had stroke after off-pump CABG and on-pump CABG, respectively. The median time for the onset of stroke was two days (range 0 to 11 days) after on-pump CABG versus four days (range 0 to 14 days) after off-pump CABG (p < 0.01). On-pump CABG was associated with a higher risk of early stroke (odds ratio 5.3, 95% confidence interval 2.6 to 10.9; p < 0.01) compared with off-pump CABG. CONCLUSIONS: Compared with off-pump CABG, on-pump CABG is associated with an earlier onset of postoperative stroke during the recovery phase, suggesting different mechanisms in the pathogenesis of stroke between the two surgical approaches.

Stroke after conventional versus minimally invasive coronary artery bypass.

BACKGROUND: Postoperative stroke is a serious complication after coronary artery bypass grafting with cardiopulmonary bypass (on-pump), and portends higher morbidity and mortality. It is unknown whether an off-pump cardiopulmonary bypass (OPCAB) approach may yield a lower stroke rate over conventional on-pump coronary artery bypass grafting. METHODS: From June 1994 to December 2000, OPCAB was performed in 2,320 patients and compared with 8,069 patients who had on-pump coronary artery bypass grafting, during the same period of time. The patients undergoing OPCAB were randomly matched to on-pump patients by propensity score. A logistic regression model was used to test the difference in the postoperative stroke rate between OPCAB and on-pump procedures controlling for the correlation between matched sets. A multiple logistic regression model predicting the risk of stroke adjusted by stroke risk factors and operation type was also computed. RESULTS: Matches by propensity score were found for 72% of the patients undergoing OPCAB. Patients undergoing on-pump coronary artery bypass grafting were 1.8 (95% confidence interval 1.0 to 3.1, p = 0.03) times more likely to suffer a stroke postoperatively than OPCAB patients after controlling for preoperative risk factors through matching. Independent predictors of stroke identified from the multiple logistic model included on-pump operation (versus OPCAB operation), female gender, 4 to 6 vessels grafted (versus <4 grafts), hypertension, history of previous cerebrovascular accident, carotid artery disease, chronic obstructive pulmonary disease, and depressed ejection fraction. CONCLUSIONS: Off-pump cardiopulmonary bypass avoids the risks of cardiopulmonary bypass and atrial trauma. A substantially lower stroke rate suggests that OPCAB is a neurologically safe treatment option for revascularization.

Elimination of cardiopulmonary bypass improves early survival for multivessel coronary artery bypass patients.

BACKGROUND: Coronary artery bypass graft (CABG) surgery performed without cardiopulmonary bypass (CPB) is currently increasing in clinical practice. Decreased morbidity associated with off-pump (OP) CABG in selected risk groups examined in relatively small, single institution groups has been the focus of most recent studies. The purpose of this study was to determine the independent impact of CPB on early survival in all isolated multivessel CABG patients undergoing surgery in two large institutions with established experience in OPCABG techniques. METHODS: A review of two large databases employed by multiple surgeons in the hospitals of two institutions identified 8,758 multivessel CABG procedures performed from January 1998 through July 2000. In all, 8,449 procedures were included in a multivariate logistic regression analysis to determine the relative impact of CPB on mortality independent of known risk factors for mortality. Procedures were also divided into two treatment groups based on the use of CPB: 6,466 had CABG with CPB (CABG-CPB), 1,983 had CABG without CPB (OPCABG). Disparities between groups were identified by univariate analysis of 17 preoperative risk factors and treatment groups were compared by Parsonnet's risk stratification model. Finally, computer-matched groups based on propensity score for institution selection for OPCABG were combined and analyzed by a logistic regression model predicting risk for mortality. RESULTS: CABG-CPB was associated with increased mortality compared with OPCABG by univariate analysis, 3.5% versus 1.8%, despite a lower predicted risk in the CABG-CPB group. CPB was associated with increased mortality by multiple logistic regression analysis with an odds ratio of 1.79 (95% confidence interval = 1.24 to 2.67). An increased risk of mortality associated with CPB was also determined by logistic regression analysis of the combined computer-matched groups based on OPCABG-selection propensity scores with an odds ratio of 1.9 (95% confidence interval = 1.2 to 3.1). CONCLUSIONS: Elimination of CPB improves early survival in multivessel CABG patients. Rigorous attempts to statistically account for selection bias maintained a clear association between CPB and increased mortality. Larger multiinstitutional studies are needed to confirm these findings and determine the most appropriate application of OPCABG.

Clinical outcomes of coronary revascularization without cardiopulmonary bypass.

OBJECTIVE: Coronary artery bypass without cardiopulmonary bypass (OPCAB) eliminates the complications related to cardiopulmonary bypass. However, the long-term outcomes of this procedure are largely unknown. METHODS: We sought to investigate the rates of late mortality, stroke, acute myocardial infarction, and target vessel reintervention after OPCAB in a consecutive series of 857 patients who underwent OPCAB between May 1987 and March 1999. RESULTS: Long-term follow-up was obtained for 86% of eligible patients. Actuarial and event-free survival was 89% and 76%, respectively, for a median follow-up period of 2.2 years (range, 0-13.3 years). Risk factors for late mortality were identified with Cox regression analysis. In the multivariate analysis, patient age >75 years (odds ratio, 1.1; 95% confidence interval, 1.0-1.1; P =.01) and an ejection fraction <35% (odds ratio, 2.7; 95% confidence interval, 1.2-6.2; P =.02) emerged as independent predictors of late mortality. CONCLUSION: OPCAB is associated with a low mortality and clinical event rate. Advanced age and depressed ejection fraction may increase mortality after OPCAB.

Confusion in revascularization: are women different and why?

Cardiovascular disease is the leading cause of death in women in most developed countries of the world. Even though cardiovascular deaths of men in the United States have been declining, until recently the number of cardiovascular deaths in US women was on the rise, with 1 in 3 women dying from heart disease. Over the last 30 years numerous studies have reported sex differences in the epidemiology, prevention, diagnosis, and clinical manifestations of coronary artery disease. A higher morbidity and mortality were also noted in women versus men undergoing revascularization during this early period. This has mainly been attributed to the fact that women have more comorbid conditions by the time that they are referred for revascularization. These conditions include increased age, hypertension, diabetes (metabolic syndrome), heart failure, renal disease, peripheral vascular disease, and worse lipid profile. With improvements of both surgical techniques and percutaneous coronary intervention, morbidity and mortality rates have decreased in women undergoing revascularization. However, there are now questions surrounding percutaneous coronary intervention strategies, particularly with drug eluting stents. More recent advances in coronary bypass graft surgery techniques, both off- and on-pump, and analysis of prospective and retrospective data have shown a clearly improved survival rate in patients undergoing coronary bypass graft surgery and the persistence of a durable result.

Clopidogrel administration prior to coronary artery bypass grafting surgery: the cardiologist's panacea or the surgeon's headache?

AIMS: Thrombotic complications after percutaneous coronary intervention procedures have decreased in past years mainly due to the use of clopidogrel antiplatelet therapy. However, the risk of bleeding due to enhanced and irreversible platelet inhibition in patients who will require surgical coronary revascularization instead has not been adequately addressed in the literature. The purpose of this study was to evaluate the effect of pre-operative clopidrogel exposure in haemorrhage-related re-exploration rates, peri-operative transfusion requirements, morbidity, and mortality in patients undergoing coronary artery bypass grafting (CABG) surgery. METHODS AND RESULTS: A study population of 2359 patients undergoing isolated CABG between January 2000 and June 2002 was reviewed. Of these, 415 (17.6%) received clopidogrel prior to CABG surgery, and 1944 (82.4%) did not. A risk-adjusted logistic regression analysis was used to assess the association between clopidogrel pre-medication (vs. no) and haemostatic re-operation, intraoperative and post-operative blood transfusion rates, and multiple transfusions received. Haemorrhage-related pre-operative risk factors identified from the literature and those found significant in a univariate model were used. Furthermore, a sub-cohort, matched-pair by propensity scores analysis, was also conducted. The clopidogrel group had a higher likelihood of haemostatic re-operation [OR = 4.9, (95% CI, 2.63-8.97), P < 0.01], an increase in total packed red blood cell transfusions [OR = 2.2, (95% CI, 1.70-2.84), P < 0.01], multiple unit blood transfusions [OR = 1.9, (95% CI, 1.33-2.75), P < 0.01] and platelet transfusions [OR = 2.6, (95% CI, 1.95-3.56), P < 0.01]. Surgical outcomes and operative mortality [OR = 1.5, (95% CI, 0.36-6.51), P = 0.56] were not significantly different. CONCLUSION: Pre-operative clopidogrel exposure increases the risk of haemostatic re-operation and the requirements for blood and blood product transfusion during, and after, CABG surgery.

Beating heart surgery in a patient with dextrocardia and complete situs inversus.

We present a 65-year-old female patient with dextrocardia and situs inversus who underwent successful coronary artery bypass without cardiopulmonary bypass. Vessels revascularized included right internal mammary artery to the left anterior descending artery and a saphenous vein graft to the first obtuse marginal branch. The procedure was performed on a beating heart through a median sternotomy with the use of a compression epicardial stabilizer. The patient was discharged to her home after an uneventful recovery. Only 12 similar cases of myocardial revascularization in patients with dextrocardia have been reported so far, and this is one of the first procedures, in patients with dextrocardia, performed off pump.

The impact of aortic manipulation on neurologic outcomes after coronary artery bypass surgery: a risk-adjusted study.

BACKGROUND: Cerebral embolization of atherosclerotic plaque debris caused by aortic manipulation during conventional coronary artery bypass grafting (CABG) is a major mechanism of postoperative cerebrovascular accidents (CVA). Off-pump CABG (OPCABG) reduces stroke rates by minimizing aortic manipulation. Consequently, the effect of different levels of aortic manipulation on neurologic outcomes after CABG surgery was examined. METHODS: From January 1998 to June 2002, 7,272 patients underwent isolated CABG surgery through three levels of aortic manipulation: full plus tangential (side-biting) aortic clamp application (on-pump surgery; n = 4,269), only tangential aortic clamp application (OPCABG surgery; n = 2,527) or an "aortic no-touch" technique (OPCABG surgery; n = 476). A risk-adjusted logistic regression analysis was performed to establish the likelihood of postoperative stroke with each technique. Preoperative risk factors for stroke from the literature, and those found significant in a univariable model were used. RESULTS: A significant association for postoperative stroke correspondingly increasing with the extent of aortic manipulation was demonstrated by the univariable analysis (CVA incidence respectively increasing from 0.8% to 1.6% to a maximum of 2.2%, p < 0.01). In the logistic regression model, patients who had a full and a tangential aortic clamp applied were 1.8 times more likely to have a stroke versus those without any aortic manipulation (95% confidence interval: 1.15 to 2.74, p < 0.01) and 1.7 times more likely to develop a postoperative stroke than those with only a tangential aortic clamp applied (95% confidence interval: 1.11 to 2.48, p < 0.01). CONCLUSIONS: Aortic manipulation during CABG is a contributing mechanism for postoperative stroke. The incidence of postoperative stroke increases with increased levels of aortic manipulation.