Search for: [Abstract = "Introduction\: Connective tissue systemic diseases such as systemic sclerosis \(SSc\), dermatomyositis \(DM\), and polymyositis \(PM\) are associated with an increased risk of cardiovascular complications. Research suggests that endothelial dysfunction, important in the context of these diseases, may be the key to understanding these phenomena. Methodology\: A case\-control study was conducted at the University Hospital in Krakow \(2014\-2019\) on 56 patients with systemic sclerosis \(SSc\) and 58 with dermatomyositis \(DM\/PM\) and 67 healthy subjects \(control group\). An automatic trombogram \(CAT\) was used to measure thrombin generation. Patients with SSc and controls were additionally subjected to echocardiography, vasodilation measurement \(FMD\) and markers of endothelial damage \(VCAM\-1, thrombomodulin\). Results\: Studies have shown that patients with DM\/PM and SSc had a higher thrombin generation potential than the control group. In the group of patients with SSc, a reduced relative increase in FMD \(Flow\-mediated dilatation\) and an increased Intima\-media thickness \(IMT\) were also observed. Conclusions\: Patients with SSc, DM\/PM show prothrombotic properties of the blood and a more intense process of activation of the coagulation, which may explain the increased risk of cardiovascular complications. More research is needed to verify the role of the altered clotting activation profile in thes"]