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Abstract: Hydrogen was introduced into palladium–silver Pd77Ag23 membrane from a gas phase and self-stresses were created. The diffusion coefficients of hydrogen were determined for Pd77Ag23 membrane with different initial contents of hydrogen at  K. The non-local fluxes of interstitial component in the opposite direction than Fick’s fluxes were observed at stress conditions. The diffusion of hydrogen through the Pd77Ag23 membrane has been compared with deuterium diffusion. For Pd77Ag23 membrane without initial content of hydrogen, the diffusion coefficients of hydrogen were determined at temperatures: 298.2, 303.2, 308.2, 318.2, 328.2 K. [Copyright &y& Elsevier]

Abstract: Permeation of interstitial components (hydrogen and deuterium) through Pd77Ag23 membrane was studied at stress conditions. Stresses were created in the process of metal lattice expansion after introduction of hydrogen or deuterium from gaseous phase into palladium–silver membrane. At T =303.2K the flows of hydrogen and deuterium in stationary states were determined for Pd77Ag23 membrane with initial contents of hydrogen and deuterium up to n 0 =0.1 (n 0, atomic ratio of hydrogen or deuterium to metal) and at different boundary conditions. The analysis of stationary state was done. [Copyright &y& Elsevier]

Background: Whether thrombus aspiration and local glycoprotein IIb/IIIa administration reduce infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not been established in multicenter studies.Design: INFUSE-AMI is a multicenter, open-label, controlled, single-blind randomized study enrolling 452 subjects with anterior STEMI and an occluded proximal or mid-left anterior descending artery with thrombosis in myocardial infarction 0, 1, or 2 grade flow undergoing primary PCI with bivalirudin anticoagulation. Subjects are randomized in a 2 × 2 factorial to one of the following 4 arms: (1) local infusion of abciximab using the ClearWay RX Local Therapeutic Infusion Catheter (ClearWay, Atrium Medical Corp, Hudson, NH) after aspiration with a 6F Export Aspiration Catheter (Medtronic, Inc, Minneapolis, MN), (2) local infusion of abciximab using the ClearWay RX Infusion Catheter and no aspiration, (3) no local infusion of abciximab and aspiration with a 6F Export Aspiration Catheter, or (4) no local infusion of abciximab and no aspiration. The primary end point is infarct size (percentage of total left ventricular mass) at 30 days measured by cardiac magnetic resonance imaging. Other secondary end points include microvascular obstruction by cardiac magnetic resonance imaging at 5 days, ST-segment resolution, angiographic myocardial perfusion, thrombus burden, angiographic complications, and clinical events through 1-year follow-up. Safety end points include major and minor bleeding.Summary: INFUSE-AMI is testing the hypothesis that the intracoronary administration of an abciximab bolus with or without thrombus aspiration before stent implantation compared to no infusion with or without thrombus aspiration reduces infarct size among patients undergoing primary PCI for anterior STEMI who are treated with bivalirudin. [ABSTRACT FROM AUTHOR]

Objectives: In the Euroinject One phase II randomized double-blind trial, therapeutic angiogenesis of percutaneous intramyocardial plasmid gene transfer of vascular endothelial growth factor (phVEGF-A(165)) on myocardial perfusion, left ventricular function, and clinical symptoms was assessed. Background: Evidence for safety and treatment efficacy have been presented in phase I therapeutic angiogenesis trials. Methods: Eighty "no-option" patients with severe stable ischemic heart disease, Canadian Cardiovascular Society functional class 3 to 4, were assigned randomly to receive, via the NOGA-MyoStar system (Cordis Corp., Miami Lakes, Florida), either 0.5 mg of phVEGF-A(165) (n = 40) or placebo plasmid (n = 40) in the myocardial region showing stress-induced myocardial perfusion defects on (99m)Tc sestamibi/tetrofosmin single-photon emission computed tomography. Results: No differences among the groups were recorded at baseline with respect to clinical, perfusion, and wall motion characteristics. After three months, myocardial stress perfusion defects did not differ significantly between the VEGF gene transfer and placebo groups (38 +/- 3% and 44 +/- 2%, respectively). Similarly, semiquantitative analysis of the change in perfusion in the treated region of interest did not differ significantly between the two groups. Compared with placebo, VEGF gene transfer improved the local wall motion disturbances, assessed both by NOGA (p = 0.04) and contrast ventriculography (p = 0.03). Canadian Cardiovascular Society functional class classification of angina pectoris improved significantly in both groups but without difference between the groups. No phVEGF-A(165)-related adverse events were observed; however, NOGA procedure-related adverse events occurred in five patients. Conclusions: The VEGF gene transfer did not significantly improve stress-induced myocardial perfusion abnormalities compared with placebo; however, improved regional wall motion, as assessed both by NOGA and by ventriculography, may indicate a favorable anti-ischemic effect. This result should encourage more studies within the field. Transient VEGF overexpression seems to be safe. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the study was to compare the influence of dual-chamber pacing vs. nonsurgical septal reduction on hemodynamic and morphological parameters in patients with obstructive form of hypertrophic cardiomyopathy. Methods: Nineteen patients with dual-chamber pacing (group I) and 9 patients who underwent nonsurgical septal reduction (group II) were studied at baseline and after a 6-month follow-up. The changes of left ventricular outflow tract gradient and posterior wall thickness (as an index of left ventricular hypertrophy regression) were compared. Results: The baseline left ventricular outflow tract gradient was comparable between group I and group II (77±25 vs. 82±25 mm Hg, p>0.05). At 6-month follow-up, the left ventricular outflow tract gradient was reduced to a similar level in both groups (28±19 vs. 25±12 mm Hg, p>0.05). At baseline, posterior wall hypertrophy was comparable between groups (12.9±1.7 vs. 13.6±2.2 mm, p>0.05). During follow-up, the posterior wall thickness was unchanged in the pacing group (12.9±1.7 vs. 12.6±1.6 mm, p>0.05), whereas nonsurgical septal reduction induced regression of left ventricular hypertrophy in myocardial region remote from the infarcted septal segment (13.6±2.2 vs. 10.5±2.3 mm, p<0.003). Conclusion: Despite comparable reduction of instantaneous left ventricular outflow tract gradient, the nonsurgical septal reduction decreased posterior wall thickness, whereas pacing did not reduce left ventricular hypertrophy. Thus, regression of left ventricular hypertrophy that appeared solely after nonsurgical septal reduction may reflect the more permanent reduction of left ventricular pressure overload. Thus, not only hemodynamic but also morphological benefit from nonsurgical septal reduction seems to indicate the superiority of this method over dual-chamber pacing. [Copyright &y& Elsevier]