The Correlation Of Fibrinolytic Activation, Lipoprotein(a) And Coronary Arterial Thrombosis

Objective: Many researches showed the unbalance of coagulation–fibrinolytic system perhaps lead to coronary arterial thrombosis. And numerous studies have shown the elevated blood lipoprotein (a) level correlate significantly to thrombosis. We evaluated the relationship between tPA, PAI-1, Lp(a) and coronary arterial thrombosis, by detecting the plasma level of tPA, PAI-1, Lp(a), combining with the coronary angiography findings.Methods: The ACS group was composed of 54 patients diagnosed as AMI and UAP. According to the number of injured vessels showed by coronary angiography, all patients were divided three groups: one branch group, two branches group and multiple branches group. The control group is composed of 42 healthy cases. The plasma levels of tPA and PAI-1 in all cases were measured by ELISA assay. The concentration of Lp(a), TG, TC, HDL-C were detected by Olympus automatic biochemical analyze apparatus. Then work out the concentration of LDL-C according to Friedewald expressions: LDL =TC-HDL-TG/2.2. All data were analyzed by SPSS11.5 software.Results: (1) The plasma levels of tPA and PAI-1 were elevated significantly in patients with AMI and UAP than in controls (P<0.05, P<0.01). PAI-1 was higher in patients with AMI than with UAP (P<0.01). The difference of tPA level between AMI and UAP was not found. (2)The plasma concentration of Lp(a) had a significant increment in patients with AMI and UAP comparing to controls (P<0.05,P<0.01). (3)The plasma levels of PAI-1 and Lp(a) had a significant increment respectively in the multiple branches group comparing to the other two groups (P<0.01), while the level of tPA had no difference among the three groups. (4)The plasma level of Lp(a) positively correlated with PAI-1(P<0.01), but not correlated with tPA (P>0.05). The concentration of TG positively correlated with tPA and PAI-1(P<0.01). The level of Lp(a) in plasma had no relationship with other lipoproteins (P>0.05).Conclusions: (1) When the coronary arterial thrombosis occurred, the fibrinolytic activation decreased and the plasma levels of tPA and PAI-1 increased, especially of PAI-1. At the same time the plasma concentration of Lp(a) increased, and it increased with the severity of coronary artery lesions. (2)Lp(a) promoted the expression of PAI-1, inhibited the secretion of tPA and decreased the activity of tPA. Thus it disturbed the dynamic equilibrium between coagulation and fibrinolysis and led to thrombosis. (3) The plasma level of TG positively correlated with tPA and PAI-1, while the level of Lp(a) had no relationship with other lipoproteins.