LIPOPROTEIN(A) CONCENTRATIONS ARE INCREASED IN PATIENTS WITH MYOCARDIAL-INFARCTION AND ANGIOGRAPHICALLY NORMAL CORONARY-ARTERIES

It is generally accepted that Lp(a) is an independent risk factor of c ardiovascular diseases. Since the apolipoprotein component of Lp(a) sh ows some homologies to plasminogen, it is, however, unclear as to whet her the pathological effect is due to the role played by the lipoprote in in lipid metabolism or in the fibrinolytic system. We compared two groups of patients with myocardial infarction, with and without angiog raphically documented coronary artery disease. In the latter group, im balances in the clotting system are very likely, while members of the former group may also display disturbances of lipid metabolism. The re sults show that the two groups display differences in lipid metabolism , whereas they have similar patterns of thrombogenicity indices and Lp (a) values. This study seems to support the hypothesis that Lp(a) does play a role in the fibrinolytic system, since even those myocardial i nfarctions without obstructive coronary artery disease have a high fre quency of Lp(a) concentrations above 300 mg/l, i. e. similar to the si tuation found in the myocardial infarctions with angiographically docu mented coronary artery disease. Whether the high Lp(a) concentrations in the two groups are related to an impaired fibrinolysis will be the subject of further investigation.