PROCOAGULANT INFLAMMATORY RESPONSES OF MONOCYTES AFTER DIRECT BALLOONANGIOPLASTY IN ACUTE MYOCARDIAL-INFARCTION

This study sought to investigate monocyte procoagulant activity and Ma c-1 expression after successful percutaneous transluminal coronary ang ioplasty (PTCA) in acute myocardial infarction (AMI). An increased leu kocyte count is an important risk factor for subsequent adverse cardia c events in AMI. Cellular procoagulant responses may contribute to the risk of thrombotic events after AMI. In 20 patients with AMI serial v enous blood samples were obtained before, 4, 8 hours, and daily after direct PTCA. Twenty patients with elective PTCA served as a control gr oup. We measured leukocyte procoagulant activity with a 1-stage clotti ng assay, Mac-1 expression of monocytes by flow cytometry, concentrati ons of tumor necrosis factor-alpha, interleukin (IL)-1 beta, IL-6, and IL-8 using immunoassays. Forty-eight hours after PTCA in patients wit h AMI, an increase in systemic IL-6 and C-reactive concentrations was found (p = 0,001, p = 0.008) associated with an increase in monocyte M ac-1 expression by 49 +/- 18% (p = 0.04) and followed by an increase i n monocyte procoagulant activity by 140 +/- 63% 72 hours after PTCA (p = 0.01). None of these changes were detectable in the central group. No changes in the concentrations of the cytokines IL-1 beta, tumor nec rosis factor-alpha, or IL-8 were found. The present study demonstrates an increase in procoagulant activity along with an increase in Mac-1 expression on circulating monocytes after successful PTCA in AMI assoc iated with an increase in systemic IL-6. These cellular procoagulant r esponses may limit the clinical benefit from timely reperfusion. (C) 1 998 by Excerpta Medica, Inc.