Use of a polysaccharide sulfate of low molecular weight for obtaining a drug active against vascular thrombosis

The invention concerns the use of a sulphated polysaccharide capable of being obtained by radical depolymerization of a raw fucan derived from Pheophyceae, said polysaccharide having a molar mass not more than 10.000 g/mol, to obtain a medicine for preventing or treating vascular thrombosis, in particular venous thrombosis, arterial thrombosis and arterial restenosis.