CLINICAL AND OPERATIVE CHARACTERISTICS OF PATIENTS RANDOMIZED TO CORONARY-ARTERY BYPASS-SURGERY IN THE BYPASS ANGIOPLASTY REVASCULARIZATIONINVESTIGATION (BARI)

The surgical cohort of the Bypass Angioplasty Revascularization Invest igation (BARI) is the largest group of patients with multivessel coron ary artery disease randomly assigned to surgical treatment. This repor t presents baseline and operative characteristics of the cohort and de scribes some aspects of the variability in surgical practice among the 14 primary clinical centers and 4 so-investigational sites participat ing in BARI. Preoperative clinical and angiographic data and intraoper ative variables were reviewed in 892 patients who were randomly assign ed to coronary artery bypass grafting (CABG) and underwent operation. Associations between patient/lesion variables and operative characteri stics are described. Of patients assigned to CABG, 87% underwent an op eration within 2 weeks of randomization, as recommended in the protoco l. Mean age of the 892 patients was 61 years, and mean age of the 235 women was greater than that of men (64 years vs 60 years); 64% of the surgical patients were classified as having unstable angina during the 6 weeks prior to randomization. Coronary angiography demonstrated 3-v essel disease (50% diameter narrowing by caliper measurement) in 41% o f patients, and disease of the left anterior descending coronary arter y was present in 87% of patients. A mean of 3.1 coronary arteries per patient were bypassed, and 82% of patients received 1 (70%) or 2 (12%) internal thoracic artery grafts. Prevalence of infernal thoracic graf ts was lower in elderly patients (74% of patients greater than or equa l to 70 years), in women (72% vs 85% in men; p < 0.01), and in black p articipants (65%). There was significant center-to-center variation in duration of cardiopulmonary bypass and aortic cross-clamping, methods of intraoperative myocardial protection, and in graft usage. Surgical patients in BARI differ considerably from patients entered into previ ous randomized trials in that the operative methods and graft usage re flect contemporary practice of coronary artery surgery, although signi ficant variations among institutions were observed.