PROMIS-HFpEF is the first prospective multi-centre, multinational study to demonstrate a high prevalence of CMD in HFpEF in the absence of unrevascularized macrovascular CAD, and to show its association with systemic endothelial dysfunction (RHI, UACR) as well as markers of HF severity (NTproBNP and RV dysfunction). Microvascular dysfunction may be a promising therapeutic target in HFpEF.

The interaction of ionic/nonionic surfactant micelles with strong polyelectrolytes has been studied by turbidimetric titrations. There exists a critical micellar fraction of ionic head groups, Yc, below which no interactions can be detected. At Y > Yc, the solute components form either soluble aggregates, complex coacervate, or amorphous precipitate, depending, in part, on the polymer:surfactant stoichiometry. The dependence of Yc on the square root of the ionic strength, P/2, appears as a linear phase boundary, which is rather insensitive to polymer concentration or total surfactant concentration. For several polyelectrolyte/mixed-micelle systems, we have measured the surface potential of the micelle ('F0) at values of Y and I corresponding to the polyion-micelle complex formation phase boundary. In the system poly-(dimethyldiallylammonium chloride)/sodium dodecyl sulfate, C12E06, the values of 'P0 measured from the pKt of the probe, dodecanoic acid, are constant (ca. -10.8 mV) along the phase boundary. For the same polymer-surfactant system, \P0 measured with the fluorescence probe hexadecylhydroxycoumarin increases with Yc from -18 to -24 mV along the phase boundary. For the system of reversed charge, sodium polystyrenesulfonate/dodecyldimethylamine oxide, in which the cationic surfactant head group itself acts as a potential probe, the surface potential varies from +12 to +43 mV along the phase boundary. The foregoing results, taken together with the absence of an effect of polymer chain length on Yc, suggest that critical conditions for complex formation are dictated by the cooperative adsorption of a relatively short sequence of polyion segments to the colloid surface. It appears likely that this process occurs when a critical potential is reached at the locus of the closest approach of the polymer chain to the micelle surface. The measured potential at critical conditions increases with the distance between this steric boundary and the mean position of the solubilized probe.

Background-Using new, very high-resolution ultrasound biomicroscopy, we examined the thickness of artificial layers of silicone and intima thickness (IT) of radial and anterior tibial arteries in healthy subjects and in patients with vascular disease. Methods and Results-Silicone layers of varying thicknesses and mesenteric artery specimens obtained from 18 patients undergoing colectomy were measured by both ultrasound biomicroscopy (55 MHz) and morphometry. There was high correlation (rϾ0.9; PϽ0.0001) between IT and intima area versus ultrasound biomicroscopy. In 90 healthy subjects (aged between 10 and 90 years), radial and anterior tibial arterial IT and intima-media thickness were measured, as was carotid intima-media thickness in 56 of these subjects. Age was strongly related with both media thickness and IT of both peripheral arteries. Correlations were found between carotid intima-media thickness and both radial and anterior tibial IT/intima-media thickness (rϭ0.44 to 0.53; PϽ0.0001). The IT-to-lumen diameter ratio increased with age and was larger at all ages in the anterior tibial artery (0.067Ϯ0.034) versus the radial artery (0.036Ϯ0.012; PϽ0.0001). A thicker radial intimal layer was found in patients with peripheral artery disease. Conclusion-This