Blood rheology in men with essential hypertension and capillary rarefaction

Abstract

The pathophysiological significance of hyperviscosity and capillary rarefaction in untreated essential hypertension is unknown. Fifty untreated hypertensive men with capillary rarefaction (intravital capillaroscopy) and 20 age-and sex-matched normotensive controls underwent full haemorheological profiling (blood viscosity at high and low shear, haematocrit, platelet and leukocyte counts, fibrinogen and total protein concentrations, P-selectin levels, erythrocyte and leukocyte filterability rates and erythrocyte deformability and aggregation indexes). Subjects with skin capillary density below the group median had younger age, higher dia-

Haemorheological, platelet and endothelial factors in essential hypertension

“…The three case-control studies [3][4][5] have extended previous research by showing an increased hyperviscosity and endothelial dysfunction among patients with hypertension who had no concomitant cardiovascular risk factors. Unlike some studies that have included severe hypertensives, all three examined either mild or newly diagnosed hypertensives who were generally middle-aged.…”

“…In summary, the four studies [3][4][5][6] have verified a role of increased platelet and endothelial activity, monocytes, cell adhesion molecules and microparticles in the pathogenesis of hypertension (alone or concurrent with diabetes). Therefore, antihypertensive medication that has simultaneous antiatherogenic or favourable haemorheological effects is likely to be significant in the prevention of vascular morbidity and mortality.…”

“…Hlubocká et al 4 noted significantly higher levels of ICAM-1, vWf, and endothelin-1 among the hypertensives compared to the normotensives, whilst no significant difference was found in levels of E-selectin, P-selectin, fibrinogen, tissue plasminogen activator (tPA) and plasminogen activator inhibitor type 1 (PAI-1). The hypertensives in the study by Ciuffetti et al 3 showed significantly higher blood vis- Table 1 Haemorheological and endothelial factors found to differ significantly between hypertensives and normotensives in three studies [3][4][5] von Willebrand factor Beta thromboglobulin Soluble thrombomodulin P-selectin Intracellular cell adhesion molecule-1 Endothelin-1 Blood viscosity Plasma viscosity Fibrinogen Red cell filterability Leucocyte filterability Red cell deformability Red cell aggregation Platelet aggregation cosity, plasma viscosity, fibrinogen and soluble Pselectin levels, together with significantly increased red blood cell filterability, unfractionated leucocyte filterability, erythrocyte deformability and erythrocyte aggregation. Furthermore, among the hypertensives, similar differences were seen for both the low and high capillary density subgroups.…”

“…[3][4][5] In addition, Ciuffetti et al 3 further divided their hypertensives into two groups based on skin capillary density (which may contribute to the increase in total peripheral resist-Journal of Human Hypertension ance among hypertensives). Moreover, Hlubocká et al 4 examined the effects of antihypertensive treatment with quinapril (an angiotensin-converting enzyme (ACE) inhibitor) on cell adhesion molecules, whilst Remková and Kratochvíl'ová 5 reported the impact of rilmenidine (a second-generation sympatholytic) therapy on endothelial and platelet function.…”

“…5 The enhanced total peripheral resistance observed among hypertensives could partly be caused by a reduction in capillary density, although the clinical significance of this capillary rarefaction is unknown. Ciuffetti et al 3 showed that hypertensives with a capillary density above the median exhibit higher levels of plasma viscosity, haematocrit and fibrinogen. In contrast, subjects with the lower capillary density show more platelet activation and impairment of leucocyte rheology.…”