Phospholipases A2 in the serum of patients after coronary artery bypass surgery.

Objective : To study the catalytic activity of phospholipase A 2 and the concentrations of group I and group II phospholipases A 2 in the sera of patients during and after coronary artery bypass surgery. Design : Prospective study. Setting : University hospital and research laboratory. Patients : Fourteen consecutive patients operated on for ischemic heart disease. Interventions : The catalytic activity of phospholipase A 2 and the serum concentrations of group I and group II phospholipases A 2 were measured before, during, and after the operation until the seventh postoperative day. A total of 196 blood samples were taken from 14 patients. Measurements and Main Results : The catalytic activity of phospholipase A 2 and the concentration of group II phospholipase A 2 increased in the sera of patients after coronary artery bypass surgery. The concentration of group I phospholipase A 2 did not change. The catalytic activity of phospholipase A 2 correlated significantly with group II but not with group I phospholipase A 2 values. Conclusions : The increase in the catalytic activity of phospholipase A 2 in serum after coronary artery bypass surgery is due to group II phospholipase A 2 . The present results suggest that group II phospholipase A 2 is responsible for the physiologic and pathophysiologic effects of catalytically active phospholipase A 2 after coronary artery bypass surgery.