Coronary bypass surgery in patients with circulating lupus anticoagulant.

Clinical and laboratory experience with circulating lupus anticoagulant in 3 patients undergoing coronary artery bypass procedures is reported. This circulatory anticoagulant inhibits activation of prothrombin by the prothrombin activator complex (factor Xa, factor V, and phospholipid). The presence of lupus anticoagulant was initially detected because of a prolonged activated partial thromboplastin time and a normal or mildly prolonged prothrombin time. The 3 patients underwent uncomplicated coronary artery bypass grafting and experienced no abnormal bleeding postoperatively. The lupus anticoagulant is a rare cause of bleeding after open-heart surgery. It appears to be a problem only when an additional coagulation defect is present.