[Lipoprotein Lp(a) as a risk factor for heart infarct--a family study].

Lp(a) concentrations, apolipoprotein A-I and B, and various lipid parameters were measured from members of 3 families in which myocardial infarction frequently occurred. No correlation could be found between Lp(a) concentration and other lipoprotein parameters. It has been demonstrated that myocardial infarction and atherosclerotic diseases occur only in patients with Lp(a) concentrations higher than 70 mg/dl. An unfavourable Apo B/Apo A-I relation or LDL/HDL relation, associated with high Lp(a) concentration seems to play a decisive role in the development of atherosclerosis or myocardial infarction. The study suggests that subjects with Lp(a) values higher than 100 mg/dl could suffer from a special form of hyperlipoproteinemia ("Hyper-Lp(a)").