Objective: To study the catalytic activity of phospholipase A2 and the concentrations of group I and group II phospholipase A2 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 A2 and the serum concentrations of group I and group II phospholipases A2 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 A2 and the concentration of group II phospholipase A2 increased in the sera of patients after coronary artery bypass surgery. The concentration of Group I phospholipase A2 did not change. The catalytic activity of phospholipase A2 correlated significantly with group II but not with group I phospholipase A2 values.
Conclusions: The increase in the catalytic activity of phospholipase A2 in serum after coronary artery bypass surgery is due to group II phospholipase A2. The present results suggest that group II phospholipase A2 is responsible for the physiologic and pathophysiologic effects of catalytically active phospholipase A2 after coronary artery bypass surgery.