Diurnal blood pressure variability in essential hypertension and vascular reactivity to isometric stress.

The present study was designed to assess the hemodynamic conditions, by means of impedance cardiography methods, and the relation existing between vascular reactivity to isometric stress (isometric handgrip test) and the day/night blood pressure variations, estimated by ABPM. Fifty unselected untreated non-obese EEH adult subjects (WHO class I) with a duration of disease not exceeding 3 years were classified as dippers or non-dippers according to commonly accepted criteria. Twenty three normotensive volunteers acted as controls. SBP, DBP, HR, CI and SVRI were assessed at rest and after IHG test. At rest dippers, non-dippers and controls showed comparable CI. SVRI were more enhanced in EEH than in controls and, although not significantly, in non-dippers than in dippers. During IHG all subjects showed a significant rise of SBP, DBP and HR; CI variations were of comparable size in all groups while SVRI increases were not. Non-dippers showed a significant SVRI rise after IHG in comparison with resting values. In dippers and in controls SVRI increment was insignificantly different in comparison with resting values. Non-dippers showed a closest correlation between BP and SVRI rise during IHG while dippers showed a less consistent association. In conclusion, our data suggest that in adults with short duration EEH the existence of non-dipper condition may be unrelated to myocardial hypertrophy. Blunted nocturnal BP fall is associated with vascular hyper-reactivity revealed by a bigger elevation of SVRI during IHG.(ABSTRACT TRUNCATED AT 250 WORDS)

Defective fibrinolytic response in atherosclerotic patients--effect of iloprost and its possible mechanism of action.

Plasma fibrinolytic activity and tissue-type plasminogen activator (t-PA) were defective in response to venous stasis in five out of ten patients with peripheral occlusive artery disease. Discontinuous infusions of iloprost, a stable synthetic analogue of prostacyclin, restored a normal fibrinolytic response in all five patients but did not induce a parallel increase of plasma t-PA. These findings suggest that in addition to the possible benefits due to its vasodilatory and antiplatelet activity, iloprost may improve the fibrinolytic activity in patients with atherosclerotic disease, providing them with further antithrombotic protection. The profibrinolytic effect of iloprost seems not to depend on its ability to induce vascular t-PA release. Rather, it might be related to its inhibitory effect on PAI release from platelets, endothelial cells and/or hepatocytes. Venous occlusion test represents an easy diagnostic approach to fibrinolytic defects, even if related to arterial disease, and may help select patients who need therapeutic intervention.