To investigate the role of plasma lipid abnormalities in ischemic cerebrovascular disease related to primary vessel disease, the authors assess lipid profiles in a hospital-based cohort of 202 consecutive patients with atherothrombotic or lacunar stroke subtypes. Lipoprotein (a) was the unique lipid parameter that differs between these two subtypes being its value twofold higher in patients with atherothrombotic than in lacunar stroke. This suggests that lipoprotein (a) promotes large vessel atheromatosis rather than small vessel arteriolosclerosis and favors thrombosis on atheromatous plaques by suppressing local fibrinolysis.