Endothelial dysfunction precedes atherosclerosis in systemic sclerosis--relevance for prevention of vascular complications.

OBJECTIVES: The pathogenesis of systemic sclerosis (SSc) includes vasculopathy with endothelial dysfunction. The aim of this study was to investigate endothelium-dependent, flow-mediated dilatation (FMD), as well as endothelium-independent, nitroglycerin-mediated dilatation (NMD) of the brachial artery and to assess common carotid intimal-medial thickness (ccIMT) in SSc patients compared with healthy controls. METHODS: FMD and NMD of the brachial artery were determined using high-resolution ultrasound imaging and the values were expressed as percentage change from baseline in 29 SSc patients and 29 healthy controls. The two groups were very similar regarding sex, age and traditional cardiovascular risk factors. In addition, common carotid arteries were assessed by duplex colour ultrasound, ccIMT determined using high resolution ultrasound and expressed in mm thickness in the same patients and controls. Correlations between FMD, NMD, ccIMT, age and the SSc subtype (diffuse or limited form) were analysed. RESULTS: In the 29 SSc patients (mean age: 51.8 yrs), the FMD was significantly lower (4.82 +/- 3.76%) in comparison with the controls (8.86 +/- 3.56%) (P < 0.001). No difference was found in NMD between patients (19.13 +/- 17.68%) and controls (13.13 +/- 10.40%) (P > 0.1). There was a tendency of increased ccIMT in SSc patients (0.67 +/- 0.26 mm) compared with healthy subjects (0.57 +/- 0.09), but this difference was not significant (P = 0.067). A significant, positive correlation between ccIMT and age in SSc (r = 0.470, P = 0.013) was detected, as well as in healthy controls (r = 0.61, P = 0.003), but no correlation was found between FMD and age. In addition, ccIMT, but not FMD and NMD, displayed significant correlation with disease duration (r = 0.472, P = 0.011). NMD displayed significant inverse correlation with the age in SSc patients (r = -0.492, P = 0.012), but not in controls. We did not find any correlation between FMD, NMD, ccIMT and SSc subtype. CONCLUSIONS: There is an impairment of endothelium-dependent vasodilatation indicated by low FMD in SSc. At the same time, the endothelium-independent dilatation assessed by NMD is still preserved giving an opportunity of nitroglycerine therapy. Carotid atherosclerosis indicated by ccIMT may occur at higher ages and after longer disease duration. Thus, the assessment of FMD in the pre-atherosclerotic stage may have a beneficial diagnostic, prognostic and therapeutic relevance.

TH1/TH2 imbalance, measured by circulating and intracytoplasmic inflammatory cytokines--immunological alterations in acute coronary syndrome and stable coronary artery disease.

To describe how peripheral immune-parameters reflect the inflammatory alterations of the atherosclerotic plaques in coronary atherosclerosis. We measured general inflammatory markers C-reactive protein (CRP) and granulocyte activity, lymphocyte subpopulations and their state of activation, evaluated circulating Th1/Th2-type cytokines, and specific intracytoplasmic cytokines. We investigated the association of immune-parameters with disease outcome and mortality. Thirty-three patients with acute coronary syndrome (ACS), 62 with stable coronary artery disease (CAD) and 58 healthy controls were studied. Peripheral blood lymphocyte subgroups were quantified by flow cytometry, soluble cytokines and autoantibodies were assessed using enzyme-linked immunosorbent assay (ELISA), while intracellular cytokine levels were measured by flow cytometry after intracellular staining. We found elevated levels of CRP and granulocyte activity in ACS versus CAD (P < 0.001, P = 0.017, respectively). Natural killer (NK) cell percentages were elevated, while percentage of T cells to the total lymphocyte count was slightly decreased in ACS compared to controls (P < 0.0001, P = 0.012, respectively). Both forms of coronary atherosclerosis showed significantly higher percentages of activated T cells than controls when stained for the activation markers HLA-DR3 and CD69(+) (ACS: P < 0.0001, P = 0.002, CAD: P < 0.0001, P = 0.018, respectively). IL-1, IL-4 and IL-10 proved significantly higher in ACS versus controls (P = 0.036, P = 0.01, P < 0.0001 respectively). Th1 to Th2 ratio shifted towards a Th1 dominance in both diseases. Both general proinflammatory markers and activated T cells signify CAD. The orchestrated proinflammatory cascade eventually leads to the development of the disease.

Metabolic syndrome X: a review.

Metabolic syndrome X is a multifaceted syndrome, which occurs frequently in the general population. It is more common in men than in women. A large segment of the adult population of industrialized countries develops the metabolic syndrome, produced by genetic, hormonal and lifestyle factors such as obesity, physical inactivity and certain nutrient excesses. This disease is characterized by the clustering of insulin resistance and hyperinsulinemia, and is often associated with dyslipidemia (atherogenic plasma lipid profile), essential hypertension, abdominal (visceral) obesity, glucose intolerance or noninsulin-dependent diabetes mellitus and an increased risk of cardiovascular events. Abnormalities of blood coagulation (higher plasminogen activator inhibitor type 1 and fibrinogen levels), hyperuricemia and microalbuminuria have also been found in metabolic syndrome X. This review summarizes the present knowledge of abnormalities in this syndrome. Each risk factor is reviewed, and potential criteria for diagnosis and therapeutic targets are discussed. Because patients with metabolic syndrome X accumulate cardiac risk factors, they should be given special attention in terms of diagnosis and treatment.