Bypass Angioplasty Revascularization Investigation Trial Research Articles

Effect of Race on the Clinical Outcomes in the Bypass Angioplasty Revascularization Investigation Trial

In observational studies, clinical outcomes for black patients with coronary disease have been worse than for white patients. There are few data from randomized trials comparing the outcomes of coronary revascularization between black patients and white patients. We analyzed data from the Bypass Angioplasty Revascularization Investigation randomized trial. At study entry, the 113 black patients had significantly higher rates of diabetes, hypertension, smoking, heart failure, and abnormal left ventricular function than the 1653 white patients. Black patients had significantly higher mortality than white patients (hazard ratio, 2.16; P<0.001), which remained significant after statistical adjustment for differences in baseline clinical characteristics (hazard ratio, 1.59; P=0.003). In a substudy of economic and quality of life outcomes, the 67 black patients had similar frequency of physician visits and use of evidence-based cardiac medications but significantly worse physical function scores than the 885 white patients. The effect of random assignment to either surgery or angioplasty on clinical outcomes was not significantly modified by race (interaction probability values >or=0.18). Clinical outcomes of black patients after coronary revascularization were worse than those of white patients in a clinical trial setting with similar treatment and access to care. The differences in outcome between black and white patients were not completely attributable to the greater levels of comorbidity among black patients at study entry.

Baseline Coronary Angiographic Findings in the Bypass Angioplasty Revascularization Investigation 2 Diabetes Trial (BARI 2D)

This report describes the baseline angiographic findings in the Bypass Angioplasty Revascularization Investigation (BARI) 2 Diabetes (BARI 2D) trial, a randomized study that was initiated after the original BARI trial (BARI 1). Unlike BARI 1, which compared coronary artery bypass graft surgery with coronary angioplasty (percutaneous coronary intervention) in patients with and without diabetes, BARI 2D is investigating early versus deferred revascularization as needed in selected patients with type 2 diabetes mellitus and significant stable coronary artery disease (CAD). This analysis included 1,773 patients without previous procedures. The intended mode of revascularization, percutaneous coronary intervention or coronary artery bypass graft surgery, was specified before randomization. Angiographic findings in those randomized to revascularization versus medical treatment were similar. Overall, the mean number of lesions >or=20% diameter stenosis was 4.6 +/- 2.3, and the myocardial jeopardy index was 46 +/- 24%. Patients selected for the coronary artery bypass graft stratum had a higher mean number of lesions >or=20% diameter stenosis (5.7 vs 4.0, p <0.0001) and a higher myocardial jeopardy index (61% vs 38%, p <0.0001) than those selected for the percutaneous coronary intervention stratum. Female gender, black race, and higher body mass index were associated with less extensive CAD, whereas a history of hypertension, age at entry, low-density lipoprotein cholesterol, and ankle-brachial index <or=0.9 were associated with more extensive CAD. In conclusion, BARI 2D patients, who by design have mild or no symptoms, demonstrate considerable variation in the extent of CAD and amount of jeopardized myocardium. Coronary arteriographic findings are consistent with the intent of the design of BARI 2D. Certain baseline and clinical features were associated with the extent of disease and myocardial jeopardy.

Long-term outcomes in non-diabetic patients with metabolic syndrome undergoing revascularization for multi-vessel coronary artery disease

Aim The influence of metabolic syndrome (MS) on long-term mortality and morbidity in multi-vessel coronary artery disease (MV-CAD) is unclear. We studied the impact of MS on long-term outcomes in non-diabetic patients (NDM) with MV-CAD undergoing coronary revascularization in the Bypass Angioplasty Revascularization Investigation (BARI) trial and registry. Methods BARI trial and registry patients were separated into those with diabetes (DM) and those without. NDM fulfilling the NCEP definition of MS were identified. Ten year follow-up data were obtained on mortality, MI and development of diabetes. The data were analyzed using Cox proportional hazard modeling. Results In the BARI trial and registry 2962 NDM were identified. Of those, 510 patients had 3 or more components of the BARI-modified NCEP definition for MS, while 445 patients had 2 components of the definition and were classified as the “mixed group”. Compared to patients without MS, both MS group (RR = 3.2, p < 0.0001) and the mixed group (RR = 1.9, p = 0.02) had a higher incidence of DM over the 10-year follow-up. Type 2 DM was found to be highly associated with 10-year mortality (RR = 1.65, p < 0.0001). However, there was no statistically significant difference in the rate of death or MI at 5 and 10 years between NDM with or without MS. In multivariate analysis, the presence of MS was not associated with 10-year mortality in the BARI population (RR = 0.93, p = 0.62). Conclusion In this BARI follow-up study, we have affirmed the role of MS in predicting the development of diabetes in NDM at baseline. The 10-year risk of mortality and MI was not greater in NDM with MS who had MV-CAD and underwent revascularization, compared to patients without MS. Further studies to evaluate MS patients with MV-CAD undergoing coronary revascularization are warranted.

Effects of Heart Failure and Diabetes Mellitus on Long-Term Mortality After Coronary Revascularization (from the BARI Trial)

This study evaluated the effect of heart failure (HF) and ejection fraction (EF) at baseline on long-term cardiac mortality in patients undergoing coronary revascularization and investigated the effect of diabetes mellitus (DM) on mortality. We evaluated long-term outcomes of patients without HF, HF and a preserved EF, and HF and a decreased EF who underwent revascularization with percutaneous transluminal coronary angioplasty or coronary artery bypass graft surgery after enrollment in the Bypass Angioplasty Revascularization Investigation (BARI) trial. Ten years after initial revascularization, cumulative rates of freedom from cardiac death were 90% in patients without HF, 75% in patients with HF and a preserved EF, and 59% in patients with HF and a decreased EF (p <0.001, 3-way comparison). In diabetic patients with HF and a preserved EF, there was a significant increase in cardiac mortality compared with patients without HF (p <0.001); however, this relation was not seen in patients without DM. In conclusion, patients with HF and a preserved EF have increased mortality over 10 years compared with those without HF. Only in patients with DM did HF with preserved EF confer additional risk.

The Final 10-Year Follow-Up Results From the BARI Randomized Trial

We sought to compare 10-year clinical outcomes in the BARI (Bypass Angioplasty Revascularization Investigation) trial patients who were randomly assigned to percutaneous transluminal coronary balloon angioplasty (PTCA) versus coronary artery bypass grafting (CABG). Angioplasty and bypass surgery have been compared in numerous studies, but long-term clinical outcomes are limited. Symptomatic patients with multivessel coronary artery disease (n = 1,829) were randomly assigned to initial treatment with PTCA or CABG and followed up for an average of 10.4 years. Analyses were conducted on an intention-to-treat basis. The 10-year survival was 71.0% for PTCA and 73.5% for CABG (p = 0.18). At 10 years, the PTCA group had substantially higher subsequent revascularization rates than the CABG group (76.8% vs. 20.3%, p < 0.001), but angina rates for the 2 groups were similar. In the subgroup of patients with no treated diabetes, survival rates were nearly identical by randomization (PTCA 77.0% vs. CABG 77.3%, p = 0.59). In the subgroup with treated diabetes, the CABG assigned group had higher survival than the PTCA assigned group (PTCA 45.5% vs. CABG 57.8%, p = 0.025). There was no significant long-term disadvantage regarding mortality or myocardial infarction associated with an initial strategy of PTCA compared with CABG. Among patients with treated diabetes, CABG conferred long-term survival benefit, whereas the 2 initial strategies were equivalent regarding survival for patients without diabetes.

Surgery Is Preferred for the Diabetic With Multivessel Disease

When angioplasty was first introduced by Andreas Gruentzig in 1977, it was envisioned as a treatment for angina pectoris refractory to medical therapy but applicable to patients who might otherwise have undergone bypass surgery. Assessment of patients before the intervention included exercise stress testing documenting ischemia, and the lesions selected for treatment were those that could be attempted using the primitive balloon angioplasty equipment that was available at that time. As the equipment for percutaneous coronary interventions (PCIs) improved, the technique was expanded to encompass a larger population of patients who otherwise would have been referred for bypass surgery. By 1990, the frequency of coronary angioplasty had increased to equal that of coronary bypass surgery. By the end of the decade, almost twice as many percutaneous interventions were being performed as were coronary bypass surgical procedures.1 As angioplasty began to infringe on the domain of bypass surgery, there was a call for randomized control trials testing the comparative value of angioplasty in traditionally surgical applications. Andreas Gruentzig proposed such a trial when angioplasty had reached a degree of maturity 6 years after the first procedure was performed. National Heart, Lung, and Blood Institute (NHLBI) funding for the first comparison of bypass surgery and angioplasty was finally obtained, and the Emory Angioplasty versus Surgery Trial (EAST) was begun in 1987, 2 years after Gruentzig’s tragic death.2 A second multicenter randomized trial, the Bypass Angioplasty Revascularization Investigation (BARI), was also approved by the NHLBI and was begun 1 year after the initiation of the EAST trial. The outcomes of these trials confirmed the overall equivalence of angioplasty and bypass surgery for patients suitable for angioplasty and were consistent with other trials initiated in Europe and South America.3 However, when the 5-year outcome of the BARI trial was reported in …

Improved Survival in Asymptomatic Diabetic Patients With High-Risk Spect Imaging Treated With Coronary Artery Bypass Grafting

The Bypass Angioplasty Revascularization Investigation trial demonstrated that symptomatic diabetics with multivessel coronary artery disease had a survival advantage with initial coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI). No published study has examined different treatments and outcome in asymptomatic diabetics. This study group consisted of 826 asymptomatic diabetics (age 62+/-12 years; 76% men) without known coronary artery disease who had abnormal myocardial perfusion during stress single photon emission computed tomography (SPECT). SPECT images were classified as low-, intermediate-, and high-risk. Early revascularization (CABG or PCI < or =4 months after SPECT) was performed in 76 patients. Survival (follow-up, 5.3+/-3.3 years) was compared in patients treated with CABG, PCI, or medical therapy. Revascularization (CABG or PCI) was performed in 54 of 261 patients with high-risk scans and was independently associated with improved survival (chi2=4.55; P=0.03 after multivariate adjustment). Subset analysis demonstrated that the survival advantage was confined to patients treated with CABG (n=39), with a 5-year survival CABG at 85%, PCI at 72%, and medical therapy at 67% (P=0.02 for 3 groups). Although CABG was associated with better survival, mortality remained high (3% per year). There was no survival advantage by treatment for patients with less-severe SPECT abnormalities. These nonrandomized data suggest that CABG improves survival in asymptomatic diabetic patients with high-risk SPECT, although revascularization was performed infrequently in these patients. These results parallel those of the Bypass Angioplasty Revascularization Investigation trial in symptomatic diabetic patients.

Letter Regarding Article by Wang et al, “Coronary Artery Spatial Distribution of Acute Myocardial Infarction Occlusions”

To the Editor: I read with interest the recent article by Wang et al1 investigating the geographical distribution of coronary thromboses causing ST-segment elevation myocardial infarctions (STEMI). The authors demonstrated that these thromboses are clustered within the proximal portions of the major epicardial coronaries. They claimed that diagnostic and therapeutic approaches designed to diagnose unstable plaques or to prevent subsequent thrombosis should focus on these high-risk locations. The authors proposed theoretical explanations for the proximal location of coronary thromboses, such as high shear stress. Gibson et al2 also studied culprit lesion location in patients with STEMI, and reported similar findings—that the majority of culprit lesions in STEMI are located within the proximal third of the major coronary arteries. These 2 articles give the impression that the proximal coronary plaques are …

Letter Regarding Article by Hlatky et al, “Medical Costs and Quality of Life 10 to 12 Years After Randomization to Angioplasty or Bypass Surgery for Multivessel Coronary Artery Disease”

To the Editor: We wish to respond to the article published recently by Hlatky and colleagues in Circulation .1 The study found that early differences between coronary artery bypass grafting (CABG) and angioplasty (PTCA) in costs and quality of life were no longer significant at 10 to 12 years and that CABG was cost-effective as compared with PTCA for multivessel disease. We would like to make a few comments on this study and its findings. The original BARI (Bypass Angioplasty Revascularization Investigation) trial2 compared PTCA with CABG for multivessel disease; however, coronary stents were not used during the initial revascularization. With the advances in technology in percutaneous coronary intervention (PCI) and widespread use of coronary stents and glycoprotein IIb/IIIa receptor antagonists since the BARI trial began, the outcome in terms of medical costs and quality of life in these patients 10 to 12 years after PTCA may well …

Outcomes of noncardiac surgery after coronary bypass surgery or coronary angioplasty in the Bypass Angioplasty Revascularization Investigation (BARI)

Purpose: Previous studies have shown that coronary artery bypass surgery reduces the risk of cardiac complications after noncardiac surgery. Whether coronary angioplasty provides equivalent protection is not known. SUBJECTS AND METHODS: Patients were randomly assigned to undergo cardiac artery bypass surgery or angioplasty as part of the Bypass Angioplasty Revascularization Investigation trial. All subsequent noncardiac surgeries during a mean (± SD) follow-up of 7.7 years were recorded among participants in the ancillary Study of Economics and Quality of Life. Rates of mortality and nonfatal myocardial infarction, length of stay, and hospital costs were compared by the original randomized assignment. RESULTS: A total of 501 patients had noncardiac surgery at a median of 29 months after their most recent coronary revascularization procedure. Mortality and nonfatal myocardial infarction within 30 days of the first noncardiac surgery occurred in 4 of the 250 of the surgery-assigned patients and in 4 of the 251 of the angioplasty-assigned patients ( P = 1.0). There were no significant differences in the mean length of hospital stay (6.3 ± 6.7 versus 6.2 ± 6.8 days; P = 0.47) or hospital cost ($8,920 ± $11,511 versus $7,785 ± $7,643; P = 0.33) between the surgery and angioplasty groups. Similar results were obtained when subsequent noncardiac procedures were included in the analysis. CONCLUSION: Rates of myocardial infarction and death after noncardiac surgery are similarly low after contemporary bypass surgery or angioplasty in patients with multivessel coronary artery disease.

Percutaneous coronary artery intervention: The last five years and the next five years

In this issue of the Journal, Peterson et al I analyze the evolution of device use and outcomes of percutaneous coronary intervention (PCI) from 1994 through 1997 using registry data from 12 US hospitals participating in the National Cardiovascular Network database. Two tmdeniable trends are apparent. First, atheroablative devices, which were initially greeted with enthusiasm, have become niche tools, at least for now. The 2 most widely used of these, directional and rotational atherectomy, have declined from a combined usage rate of approximately 25% of all PCI procedures in 1994 to less than 10% in 1997. Second, during the same period there has been a dramatic increase in the use of stents from 5% to 69%, with an associated increased rate of procedural success and a decreased need for in-hospital repeat revascularization. These findings are provocative and raise many impor tant questions: (1) Are these trends in device use and outcome confirmed by other data sets? (2) Why has stent use increased so dramatically, and what impact has this had on the overall use of both PCI and surgical coronary revascularization? (3) Why have atheroablative techniques been reduced to niche status? (4) What are the limitations of coronary stenting, and can they be overcome? (5) What changes will occur over the next 5 years? The increased use of stents is confirmed by a wide variety of mult icenter surveys, registry data, and singlecenter experiences. For example, in a 1-week survey in May 1997 conducted at the 17 centers participating in the BARI (Bypass Angioplasty Revascularization Investigation) trial, 57% of the 370 patients undergoing PCI received stents. 2 In New York state, where all PCI procedures are reported in an audited registry, the percentage of patients receiving intracoronary stents has increased from 5% in 1994 to 81% in 1998, with an associated decrease in the need for bypass surgery within 24 hours of PCI from 1.7% in 1994 to 0.4% in 1998. At New York University, where more current data are available, stent use has increased from 4% of procedures in 1994 to 88% of procedures in the first 6 months of 1999.

Clinical correlates of the initial and long-term cost of coronary bypass surgery and coronary angioplasty

Background Medical costs vary substantially among patients. Understanding the baseline factors that predict subsequent cost may allow better selection of therapy for individual patients. Understanding the postprocedure events that increase cost should help to improve efficiency and effectiveness of coronary revascularization. Methods Data on 4-year costs were collected from patients randomly assigned to coronary angioplasty or bypass surgery as part of the BARI (Bypass Angioplasty Revascularization Investigation) trial. Regression models first examined factors known at the time of randomization that prospectively predicted initial procedure cost and long-term cost. Subsequent models tested the value of postrandomization events as explanatory variables for cost. Results The independent baseline predictors of higher initial percutaneous transluminal coronary angioplasty cost included 3-vessel disease (+12%) and acute presentations (+22%), whereas the independent predictors of higher initial coronary artery bypass grafting cost included the number of comorbid conditions (+5% per condition) and female sex (+7%). The independent baseline predictors of 4-year cost included heart failure (+26%), diabetes (+22%), comorbidity (+10%), and angioplasty assignment in patients with 2-vessel disease (–15%). Postrandomization models showed higher initial and long-term costs were strongly correlated with the number of repeat revascularization procedures (+30% to +128%) and the occurrence of clinical complications (+8% to +131%). Conclusions Two-vessel disease identifies patients likely to have lower costs after angioplasty, whereas heart failure, comorbid conditions, and diabetes identify patients likely to accrue higher costs after either angioplasty or bypass surgery. Long-term costs can be potentially reduced by interventions that decrease procedural complications or reduce the need for repeat revascularization. (Am Heart J 1999;138:376-83.)

Effect of age in the bypass angioplasty revascularization investigation (BARI) randomized trial

Background. The influence of age on the relative success of either percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass grafting (CABG) in patients requiring myocardial revascularization continues to be controversial. Methods. In the Bypass Angioplasty Revascularization Investigation (BARI) trial, 1,829 patients with symptomatic multivessel coronary artery disease requiring revascularization were randomly assigned to undergo either CABG or PTCA. Results. Seven hundred nine patients (39%) were 65 to 80 years old at baseline; the other 1,120 were younger than 65 years. The in-hospital 30-day mortality rate for PTCA and CABG in the younger patients was 0.7% and 1.1%, respectively, and that for patients 65 years or older was 1.7% and 1.7%, respectively. In older compared with younger patients, stroke was more common after CABG (1.7% versus 0.2%, p = 0.015) and heart failure or pulmonary edema was more common after PTCA (4.0 versus 1.3%, p = 0.011). In both age groups, CABG resulted in greater relief of angina and fewer repeat procedures. The 5-year survival rate in patients younger than 65 years was 91.5% for CABG and 89.5% for PTCA. In patients 65 years or older, the 5-year survival rate was 85.7% for CABG and 81.4% for PTCA. Cardiac mortality at 5 years was greater in patients assigned to the PTCA group than in those assigned to the CABG group. However, no significant treatment differences were noted in cardiac mortality when only nondiabetic patients were examined. Conclusions. Within the context of the Bypass Angioplasty Revascularization Investigation trial, older patients with multivessel coronary disease do well with either PTCA or CABG. Compared with younger patients, older patients had less recurrent angina and were less likely to undergo repeat procedures, particularly among those assigned to undergo CABG. Cardiac mortality was greater in patients 65 years or older assigned to undergo PTCA; however, this difference was not noted when treated diabetic patients were excluded from analysis.

Contemporary practice of coronary revascularization in U.S. hospitals and hospitals participating in the bypass angioplasty revascularization investigation (BARI)

Objectives. To assess generalizability of the Bypass Angioplasty Revascularization Investigation (BARI), we conducted a separate study comparing revascularization in U.S. and BARI hospitals.Background. The BARI trial is a multicenter investigation comparing initial revascularization with percutaneous transluminal coronary angioplasty and coronary bypass graft surgery in patients with symptomatic multivessel coronary disease.Methods. All revascularization procedures during 5 consecutive workdays were surveyed at 75 U.S. hospitals offering coronary angioplasty and bypass surgery and at all BARI hospitals. Data collected were demographics, extent of disease and type of current and previous revascularization.Results. At both U.S. and BARI hospitals, 57% of all revascularization procedures were coronary angioplasty and 43% were bypass surgery. The U.S. hospitals had m ore patients with single-vessel disease, acute myocardial infarction and primary procedures. Other characteristics were similar. The majority of revascularization procedures were angioplasty for single-vessel disease (U.S. 32% vs. BARI 25%) and bypass surgery for triple-vessel disease (U.S. 31% vs. BARI 31%). Overall, the choice between bypass surgery and angioplasty was similar in BARI and U.S. hospitals (adjusted odds ratio [OR] 1.0, p = 0.914). However, older patients were more likely and younger patients less likely to undergo bypass surgery in BARI versus U.S. hospitals (older patients: adjusted OR 1.6, p = 0.031; younger patients: adjusted OR 0.6, p = 0.028). The BARI protocol would have excluded 65% of all candidates for revascularization, for whom indications already exist for angioplasty or bypass surgery, and another 23%, for whom angioplasty would be contraindicated for individual lesions.Conclusions. Patients undergoing coronary revascularization in BARI and U.S. hospitals were generally similar, as was the choice between types of revascularization. Results from the BARI trial apply to ∼300 (12%) candidates for coronary revascularization/workday.

Interventional Cardiology Techniques for Coronary Artery Disease

This review updates and extends observations made in this journal in March 1988. The focus then was on percutaneous transluminal coronary angioplasty and the clinical results of its practical application. A concern was expressed that science lagged in solving the major problems of rethrombosis and restenosis. The NHLBI Bypass Angioplasty Revascularization Investigation (BARI) study was still in the planning phase. In 1991, the scene has changed. Interventional cardiology now embraces a multitude of different catheter devices--angioplasty, atherectomy, laser, stents. Basic scientists are increasingly involved in addressing the restenosis issue. Our national heart meetings are increasingly oriented towards molecular biology approaches to solving the remaining problems. The BARI trial has nearly completed patient entry, and we eagerly await its results. The cardiologist and surgeon are faced with increasingly complex decisions with respect to interventional technologies, involving not only whether to use them, but which ones.