Plasminogen activation in unstable angina is associated with an acute phase reaction, but does not correlate with other indexes of thrombotic or fibrinolytic activity

In Unstable Angina (UA) an acute phase response and an increase in plasminogen have been reported. To assess whether plasminogen activation is related to the hemostatic or to the inflammatory systems in UA, we measured plasma levels of Plasmin-α2-antiplasmin (PAP), C-Reactive protein (CRP) and Thrombin-AntiThrombin HI (TAT), as markers of plasminogen activation, inflammation and thrombin production, respectively. We also measured plasma levels of D-Dimer (DD), a fibrin degradation product, to assess actual lysis of fibrin. We studied 47 pts admitted to our CCU for severe UA. Blood samples were taken at CCU admission. Results (median and range): Elevated levels were considered above mean +2 SD for PAP (700 ng/ml), DD (30μg/l) and TAT (6 μg/ml) and levels >3 mg/l for CRP (90° percentile of healthy subjects). Elevated levels of PAP were observed in 18/47 pts (38%), but elevated levels of DD and TAT were found only in 9/47 pts (19%). Conversely CRP was raised in 28/47 pts (60%). PAP levels (594ng/ml, 234-1899) did not correlate with levels of DD (12.1μg/1, range 1.9-182; p=ns) or of TAT (2.1μg/ml, range 0.8-39, p=ns). Conversely a significant correlation was observed between PAP and CRP (3.7 mg/1, range 0.4-82; r=0.45, p=0.005), as well as between TAT and DD (r=0.3, p=0.047). Conclusions: An increased plasminogen activation is common in UA, but is not associated to a similar activation of the hemostatic system, as detectable by TAT and DD, but correlates with levels of the acute phase protein CRP, suggesting that in unstable angina a strong endothelial activation may have place, as source of plasminogen production, possibly on an inflammatory basis.