Five-Year Outcomes after On-Pump and Off-Pump Coronary-Artery Bypass.

BACKGROUND: Coronary-artery bypass grafting (CABG) surgery may be performed either with cardiopulmonary bypass (on pump) or without cardiopulmonary bypass (off pump). We report the 5-year clinical outcomes in patients who had been included in the Veterans Affairs trial of on-pump versus off-pump CABG. METHODS: From February 2002 through June 2007, we randomly assigned 2203 patients at 18 medical centers to undergo either on-pump or off-pump CABG, with 1-year assessments completed by May 2008. The two primary 5-year outcomes were death from any cause and a composite outcome of major adverse cardiovascular events, defined as death from any cause, repeat revascularization (CABG or percutaneous coronary intervention), or nonfatal myocardial infarction. Secondary 5-year outcomes included death from cardiac causes, repeat revascularization, and nonfatal myocardial infarction. Primary outcomes were assessed at a P value of 0.05 or less, and secondary outcomes at a P value of 0.01 or less. RESULTS: The rate of death at 5 years was 15.2% in the off-pump group versus 11.9% in the on-pump group (relative risk, 1.28; 95% confidence interval [CI], 1.03 to 1.58; P=0.02). The rate of major adverse cardiovascular events at 5 years was 31.0% in the off-pump group versus 27.1% in the on-pump group (relative risk, 1.14; 95% CI, 1.00 to 1.30; P=0.046). For the 5-year secondary outcomes, no significant differences were observed: for nonfatal myocardial infarction, the rate was 12.1% in the off-pump group and 9.6% in the on-pump group (P=0.05); for death from cardiac causes, the rate was 6.3% and 5.3%, respectively (P=0.29); for repeat revascularization, the rate was 13.1% and 11.9%, respectively (P=0.39); and for repeat CABG, the rate was 1.4% and 0.5%, respectively (P=0.02). CONCLUSIONS: In this randomized trial, off-pump CABG led to lower rates of 5-year survival and event-free survival than on-pump CABG. (Funded by the Department of Veterans Affairs Office of Research and Development Cooperative Studies Program and others; ROOBY-FS ClinicalTrials.gov number, NCT01924442 .).

Comparing off-pump and on-pump clinical outcomes and costs for diabetic cardiac surgery patients.

BACKGROUND: Observational studies have documented an off-pump over on-pump advantage for high-risk patients, including diabetic patients. Randomized trials have not confirmed this advantage. The VA Randomization On Versus Off Bypass (ROOBY) trial randomly assigned 2,203 coronary artery bypass graft surgery (CABG) patients at 18 sites to either on-pump (n=1,099) or off-pump (n=1,104) procedures. An a priori ROOBY aim was to evaluate treatment impact on diabetic patients. METHODS: Actively treated diabetic patients (n=835, receiving oral hypoglycemic or insulin medications) received off-pump CABG (n=402) or on-pump CABG (n=433). The primary ROOBY trial endpoints were a short-term composite (30-day operative death or major complications) and a 1-year composite (death, nonfatal acute myocardial infarction, or repeat revascularization). Secondary ROOBY endpoints included 1-year all-cause death, 1-year graft patency, 1-year changes from baseline in neurocognitive status and health-related quality of life, and costs. RESULTS: Diabetic patients' risk factors at baseline were balanced across treatments. For diabetic patients, the primary short-term composite outcome rate showed a worse trend for off-pump (8.0%) than on-pump (3.9%, p=0.013), with no difference in the 1-year primary composite outcome or 1-year death rate. One-year patency was 83.1% off-pump versus 88.4% on-pump (p=0.004). No differences were found in neurocognitive, health-related quality of life, discharge cost, and 1-year cumulative cost. CONCLUSIONS: Concordant with the ROOBY trial's overall findings, off-pump CABG yielded no advantage over on-pump CABG for actively treated diabetic patients. The 1-year graft patency was lower and the short-term composite trended higher for off-pump CABG, with no other significant outcome or cost differences.

Effect of clopidogrel use post coronary artery bypass surgery on graft patency.

BACKGROUND: Clopidogrel use post coronary artery bypass grafting (CABG) has become more popular under the assumption that it improves graft patency. The purpose of this sub-analysis from the Randomized On and Off-Pump Bypass (ROOBY) trial is to evaluate the role of clopidogrel use post CABG to improve graft patency when added to standard aspirin therapy. METHODS: The ROOBY trial was a multi-center, randomized, controlled clinical trial that compared on-pump versus off-pump coronary artery bypass grafting (CABG). Clopidogrel use post CABG was left at the discretion of the operator. Detailed data regarding the use and timing of clopidogrel post CABG were collected prospectively, along with 1-year angiograms to evaluate graft status. RESULTS: Of the 2,203 subjects undergoing CABG, 953 patient records had complete clopidogrel use and 1-year angiographic data. Of these, 345 (36.2%) received clopidogrel post CABG prior to discharge. Compared with patients with no post-CABG clopidogrel use, baseline characteristics were similar for the clopidogrel group except for the following: lower preoperative aspirin use (80.2% vs 86.7%, p = 0.009); higher preoperative clopidogrel use (23.5% vs 14.0%, p < 0.001), less on-pump (35.9% vs 55.9%, p < 0.0001); and lower endoscopic vein harvesting (30.8% vs 42.5%, p < 0.001) rates. Overall 1-year graft patency rates were not different between the clopidogrel and no-clopidogrel groups (86.5% vs 85.3%, p = 0.43). Multivariable analyses did not alter these findings. CONCLUSIONS: This study suggests that routine post-CABG clopidogrel use may not translate to improved 1-year graft patency. Future studies appear warranted to better define the role of more aggressive antiplatelet therapy post CABG on graft patency and clinical outcomes.

Chronic obstructive pulmonary disease impact upon outcomes: the veterans affairs randomized on/off bypass trial.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) are at inherent risk for higher rates of adverse events after coronary artery bypass graft surgery (CABG). As compared with on-pump CABG (ONCAB), it has been suggested that beating heart or off-pump CABG (OPCAB) may differentially benefit high-risk COPD patients. METHODS: Intraoperative, 30-day and 1-year outcomes were compared for COPD patients randomized to OPCAB (n = 220) versus ONCAB (n = 238) within the Veterans Affairs' Randomized On/Off Bypass (ROOBY) trial. As COPD patients may more likely incur adverse post-CABG outcomes, a propensity analysis was performed comparing all ROOBY patients with COPD (n = 458) versus those without COPD (n = 1,745). RESULTS: For COPD patients, the baseline characteristics were similar between the 2 revascularization approaches. In these patients, the intraoperative complication rate was higher with OPCAB than ONCAB (21.9% vs 10.1%, respectively; p < 0.001), but there were no significant differences in the 30-day (7.3% vs 7.6%, p = 1.00) or 1-year composite outcome rates (9.5% vs 7.1%, p = 0.39) between the groups. Comparing the COPD patients with propensity-matched non-COPD patients, there was no difference in 1-year major adverse cardiovascular events (including the 1-year composite major adverse cardiac events (MACE) outcome, as well as the individual MACE outcomes for all cause death, acute myocardial infarction, or repeat revascularization). CONCLUSIONS: In COPD patients, there were more intraoperative complications and no differences in 30-day or 1-year outcomes with OPCAB as compared with ONCAB. Similar to patients without COPD, there was no benefit to using an OPCAB approach in COPD patients.

On-pump versus off-pump coronary artery bypass surgery: cost-effectiveness analysis alongside a multisite trial.

BACKGROUND: Questions have been raised about the costs and outcomes for patients receiving on-pump and off-pump coronary artery bypass graft surgery. As part of the Department of Veterans Affairs Randomized On/Off Bypass (ROOBY) multisite trial, a cost-effectiveness analysis was performed to compare on-pump versus off-pump patients' quality-adjusted life-years and costs at 1 year. METHODS: One-year outcomes and costs (standardized to 2010 dollars) were estimated in multivariate regression models, controlling for site and baseline patient factors. The 1-year incremental cost-effectiveness analysis ratio with 95% confidence intervals was calculated using bootstrapping. RESULTS: Eighteen centers randomly assigned 2,203 participants to on-pump (n=1,099) versus off-pump (n=1,104) coronary artery bypass graft surgery. Both groups' quality of life improved significantly after surgery (p<0.01) compared with baseline, but no differences were found between treatment groups. Adjusted cost of the index coronary artery bypass graft surgery hospitalization was $36,046 on-pump and $36,536 off-pump (p=0.16). At 1 year, on-pump adjusted cost was $56,023 versus $59,623 off-pump (p=0.046). Off-pump-to-on-pump conversions after first distal anastomosis (4.8%) had significantly higher 1-year costs. Excluding conversions, there were no significant differences between treatments for index hospitalization or 1-year total costs. CONCLUSIONS: At 1 year, off-pump coronary artery bypass graft surgery was more expensive than on-pump when late off-pump-to-on-pump conversions were included. Excluding late conversions, there was no difference in quality-adjusted life-years or costs. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00032630; http://clinicaltrials.gov/ct2/show/NCT00032630.

Changes in health-related quality of life in off-pump versus on-pump cardiac surgery: Veterans Affairs Randomized On/Off Bypass trial.

BACKGROUND: The relative benefits of performing coronary artery bypass graft surgery off-pump versus on-pump continue to be debated. A critical, patient-centered outcome is health-related quality of life; yet there has been limited evaluation in large-scale, multicenter trials of the off-pump versus on-pump impact upon quality of life. METHODS: The Veterans Affairs Randomized On/Off Bypass trial randomized 2,203 nonemergent patients to off-pump or on-pump from February 2002 to May 2007. Patients completed a general quality of life survey (VR-36) and a disease-specific quality of life survey, the Seattle Angina Questionnaire (SAQ), prior to surgery, then again at 3 and 12 months post-bypass. RESULTS: Of the 2,130 1-year survivors, 1,805 patients (85%) completed 1-year surveys. Randomization resulted in comparable baseline patient characteristics, including VR-36 and SAQ scores. At 3 months and 1-year post-procedure, there were no clinically relevant differences between off-pump and on-pump patients in any of the quality of life measures. Both groups had statistically significant, comparable improvements in the physical component scale of the VR-36, and in the SAQ scales. CONCLUSIONS: For this trial's male, low-to-moderate risk, veteran population, there were no significant differences between off-pump and on-pump with regard to 1-year general and disease-specific quality of life outcomes. Both treatment arms experienced some improvements by 3 months, with continued improvements through 1-year post-bypass.

Off-Pump coronary artery bypass surgery is associated with worse arterial and saphenous vein graft patency and less effective revascularization: Results from the Veterans Affairs Randomized On/Off Bypass (ROOBY) trial.

BACKGROUND: The Department of Veterans Affairs Randomized On/Off Bypass (ROOBY) trial compared clinical and angiographic outcomes in off-pump versus on-pump coronary artery bypass graft (CABG) surgery to ascertain the relative efficacy of the 2 techniques. METHODS AND RESULTS: From February 2002 to May 2007, the ROOBY trial randomized 2203 patients to off-pump versus on-pump CABG. Follow-up angiography was obtained in 685 off-pump (62%) and 685 on-pump (62%) patients. Angiograms were analyzed (blinded to treatment) for FitzGibbon classification (A=widely patent, B=flow limited, O=occluded) and effective revascularization. Effective revascularization was defined as follows: All 3 major coronary territories with significant disease were revascularized by a FitzGibbon A-quality graft to the major diseased artery, and there were no new postanastomotic lesions. Off-pump CABG resulted in lower FitzGibbon A patency rates than on-pump CABG for arterial conduits (85.8% versus 91.4%; P=0.003) and saphenous vein grafts (72.7% versus 80.4%; P<0.001). Fewer off-pump patients were effectively revascularized (50.1% versus 63.9% on-pump; P<0.001). Within each major coronary territory, effective revascularization was worse off pump than on pump (all P≤0.001). The 1-year adverse cardiac event rate was 16.4% in patients with ineffective revascularization versus 5.9% in patients with effective revascularization (P<0.001). CONCLUSIONS: Off-pump CABG resulted in significantly lower FitzGibbon A patency for arterial and saphenous vein graft conduits and less effective revascularization than on-pump CABG. At 1 year, patients with less effective revascularization had higher adverse event rates. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00032630.

Outcomes after conversion in the Veterans Affairs randomized on versus off bypass trial.

BACKGROUND: The Randomized On versus Off Bypass trial reported conversion of 12.4% (n = 137) off-pump coronary artery bypass (OPCAB) patients and 3.6% (n = 40) on-pump cardiopulmonary bypass (CPB) patients. This paper explored outcomes after conversions. METHODS: Elective and urgent CABG patients (n = 2,203) at 18 sites were studied. Randomization within 54 participating surgeons occurred preoperatively, after which conversion occurred if clinically indicated. Conversion reasons and outcomes were captured prospectively with additional details retrospectively extracted from patient records by a core clinical group. RESULTS: Conversion rates varied considerably across participating surgeons. Converted OPCAB patients had more right coronary disease and coronary targets less than 1.5 mm. Conversions were elective in 49.3% of cases, urgent in 27.2%, or emergent in 23.5%. Elective conversions were mainly for poor exposure-intramyocardial vessel (35.8%). Urgent and emergent conversions were usually for hemodynamic instability (89.2% and 75.0%, respectively). Compared with CPB and OPCAB patients, OPCAB-converted patients had more 30-day complications and deaths (composite outcome rate of 5.7% and 5.5% vs 17.5% respectively, p < 0.001). Thirty-day outcomes for OPCAB-converted patients trended worse for emergent versus elective conversions (31.3% vs 13.4%, respectively, p = 0.05). One-year composite outcome rate (death, nonfatal myocardial infarction or revascularization) in OPCAB-converted patients was worse than in CPB patients (13.5% vs 7.1%, p = 0.02), but similar to OPCAB-nonconverted (9.4%). CONCLUSIONS: The OPCAB patients requiring conversion had worse 30-day and 1-year outcomes. The OPCAB patients with right coronary artery disease or small targets were more often converted. The 30-day composite outcome trended worst for emergent OPCAB conversions.

On-pump versus off-pump coronary-artery bypass surgery.

BACKGROUND: Coronary-artery bypass grafting (CABG) has traditionally been performed with the use of cardiopulmonary bypass (on-pump CABG). CABG without cardiopulmonary bypass (off-pump CABG) might reduce the number of complications related to the heart-lung machine. METHODS: We randomly assigned 2203 patients scheduled for urgent or elective CABG to either on-pump or off-pump procedures. The primary short-term end point was a composite of death or complications (reoperation, new mechanical support, cardiac arrest, coma, stroke, or renal failure) before discharge or within 30 days after surgery. The primary long-term end point was a composite of death from any cause, a repeat revascularization procedure, or a nonfatal myocardial infarction within 1 year after surgery. Secondary end points included the completeness of revascularization, graft patency at 1 year, neuropsychological outcomes, and the use of major resources. RESULTS: There was no significant difference between off-pump and on-pump CABG in the rate of the 30-day composite outcome (7.0% and 5.6%, respectively; P=0.19). The rate of the 1-year composite outcome was higher for off-pump than for on-pump CABG (9.9% vs. 7.4%, P=0.04). The proportion of patients with fewer grafts completed than originally planned was higher with off-pump CABG than with on-pump CABG (17.8% vs. 11.1%, P<0.001). Follow-up angiograms in 1371 patients who underwent 4093 grafts revealed that the overall rate of graft patency was lower in the off-pump group than in the on-pump group (82.6% vs. 87.8%, P<0.01). There were no treatment-based differences in neuropsychological outcomes or short-term use of major resources. CONCLUSIONS: At 1 year of follow-up, patients in the off-pump group had worse composite outcomes and poorer graft patency than did patients in the on-pump group. No significant differences between the techniques were found in neuropsychological outcomes or use of major resources. (ClinicalTrials.gov number, NCT00032630.).

Does preoperative hemoglobin independently predict short-term outcomes after coronary artery bypass graft surgery?

BACKGROUND: The role of preoperative hemoglobin in predicting short-term coronary artery bypass graft (CABG) surgery outcomes has not been well established. This study investigated the association between preoperative hemoglobin level with 30-day operative mortality and perioperative complications. METHODS: For the period from 1997 to 2005, the Department of Veterans Affairs Continuous Improvement in Cardiac Surgery Program database was used to extract 36,658 CABG-only deidentified records for patients undergoing cardiopulmonary bypass. Univariate and multivariate statistical models were used to predict both mortality and morbidity outcomes for varying levels of hemoglobin. RESULTS: Unadjusted odds of 30-day operative mortality for patients with preoperative hemoglobin level less than 10 g/dL were 2.37 times higher than for patients with hemoglobin levels of 10 g/dL or greater (95% confidence interval: 1.84 to 3.05; p < 0.0001). Multivariable effect upon 30-day operative mortality decreased considerably (odds ratio = 1.29, 95% confidence interval: 0.99 to 1.68; p = 0.064). CONCLUSIONS: As several risk factors may occur concurrently with low hemoglobin, preoperative hemoglobin level less than 10 g/dL was not a strong independent predictor of 30-day operative mortality or perioperative morbidity in multivariate models for on-pump CABG-only patients. Hemoglobin and serum creatinine were correlated, with creatinine exhibiting the stronger association with mortality. These findings suggest that moderate or severe anemia may be intertwined with other risk factors, such as serum creatinine or congestive heart failure. For a CABG patient subgroup presenting with a complex clinical preoperative profile, therefore, risk-model approaches may be inherently limited in separately identifying the predictors of anemic patients' outcomes.

Patency outcomes of aortic connectors.

OBJECTIVE: : Controlled outcome analysis of mechanical aortic connectors for proximal saphenous vein bypass graft anastomosis is lacking. We report the clinical and angiographic outcome of patients receiving the Symmetry aortic connector (St. Jude Medical, Inc St. Paul, MN, US) within a multicenter, prospective, randomized study. METHODS: : Twenty-five patients at 3 study sites received aortic connectors at the time of coronary artery bypass surgery. Protocol-defined angiographic follow-up was completed in 19 of 25 patients (76%) at time-points up to 14 months postoperatively; 32 connector anastomoses were evaluated in these 19 patients. Beating heart surgery was performed in 17 patients, and 2 were performed with cardiopulmonary bypass. Age was 69.7 ± 8.1 year; all patients were males. RESULTS: : The connector anastomosis patency rate was 15.6% (5/32). There were no deaths during the follow-up period. Four patients (21%) suffered myocardial infarction and 2 additional patients (10.5%) required percutaneous coronary interventions; one of who required 3 percutaneous coronary interventions, the other received one percutaneous coronary intervention. CONCLUSIONS: : In this nonrandomized cohort of patients, occlusion rate with Symmetry connectors was significantly greater than anticipated. Patients who have received these connectors during coronary artery bypass surgery may require closer follow-up and evaluation. While the manufacturer has stopped producing this device, there has been no recall of the product, clinical support remains ongoing, and next generation connectors have now been marketed. Consideration should be given to discontinuation of the clinical use of Symmetry connectors.