PLASMA LIPOPROTEIN(A) LEVELS AND FIBRINOLYTIC-ACTIVITY IN PATIENTS WITH UNSTABLE ANGINA

The relationships between plasma Lipoprotein(a) (Lp(a)) levels and pla sminogen activator inhibitor (PAI) activity and tissue plasminogen act ivator (t-PA) antigen levels were studied in 15 patients with unstable angina. Plasma levels of Lp(a) (mg/dl) were significantly higher in p atients with unstable angina after treatment 2 weeks than on admission (19.7 +/- 2.8 vs 14.6 +/- 2.3, p<0.01). On the other hand, the plasma levels of PAI activity (IU/ml) and t-PA antigen (ng/ml) in patients w ith unstable angina were significantly higher on admission than after treatment (PAI activity: 11.4 +/- 1.4 vs 7.7 +/- 1.5, t-PA antigen: 8. 7 +/- 0.9 vs 7.0 +/- 0.9, p<0.01). We conclude that patients with unst able angina have reduced fibrinolytic capacity, as indicated by increa sed PAI activity, and that the plasma Lp(a) level may be decreased due to binding with fibrin during the acute stage of unstable angina.