['Studies on the safety of aprotinin in coronary artery surgery have given conflicting results. Therefore, we studied the possible link between perioperative aprotinin treatment and renal dysfunction in patients undergoing first-time coronary surgery with a high risk of bleeding.', 'We performed a matched cohort study, comparing 200 patients receiving high-dose aprotinin with 200 patients receiving tranexamic acid during primary isolated coronary surgery. Patients were matched according to age, sex, and presence of acute coronary syndrome. Primary outcome was fractional change in creatinine clearance. Secondary outcomes were other evaluations of postoperative renal function, mortality, stroke, reoperation for bleeding, and transfusion requirements.', 'The groups were similar in baseline characteristics except that triple-vessel disease and history of myocardial infarction were more prevalent in the aprotinin group. No significant differences were found in fractional change in creatinine clearance (-11% versus -12%, medians, p = 0.75) or any other assessments of postoperative renal function between the tranexamic acid and the aprotinin group. Adverse event rates were similar: early mortality (3.5% versus 4.5%, p = 0.80), stroke (1.5% versus 2%, p = 1.0), reoperation for bleeding (3.5% versus 2.5%, p = 0.77), and 5-year survival (87% versus 84%, p = 0.17). Patients in the aprotinin group received fewer transfusions (48% versus 60.5%, p = 0.02), fewer units of packed red blood cells (2.0 versus 1.4, p = 0.02) and plasma (1.3 versus 0.5, p < 0.001), but more units of platelets (0.1 versus 0.2, p = 0.02).'] Is aprotinin associated with postoperative renal impairment after primary coronary surgery?