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BACKGROUND: Hypertensive heart disease (HHD) is a leading contributor to heart failure with preserved ejection fraction (HFpEF). However, the mechanisms behind the transition to the symptomatic phase remain unclear. OBJECTIVES: We sought to find the association of the exercise response of left atrial (LA) mechanical function with functional capacity, symptoms, and outcome across the heart failure (HF) spectrum in hypertension. METHODS: Echocardiography (including LA reservoir peak atrial longitudinal strain [PALS] and peak atrial contractile strain [PACS] and LA stiffness index) was performed at rest and immediately postexercise in 139 patients with HHD-35 with stage A, 48 with stage B, and 56 with stage C HFpEF. Patients were followed for HF and atrial fibrillation. RESULTS: Exercise capacity was progressively worse from stage A through stage B to stage C and was accompanied by a gradual impairment of changes in PALS and PACS from rest to exercise, whereas LA stiffness reserve remained unchanged until stage C. Peak atrial longitudinal strain and PACS reserves were independently associated with exercise capacity (P = .017 and .008, respectively). Left atrial stiffness reserve and E/e' were the strongest associations of symptomatic HF. Over a median of 25 months, 35 patients developed HF and/or atrial fibrillation. Peak atrial longitudinal strain and PACS reserves were associated with the study end points after adjusting for age, diabetes, N-terminal pro-B type natriuretic peptide, LA volume index, resting E/e', and resting PALS/PACS. CONCLUSIONS: Impaired exercise reserve of LA strain and stiffness are associated with reduced functional capacity in hypertension, and LA strain reserve is independently associated with outcome. These parameters appear to be determinants of progression to overt HF in HHD; however, their contribution may differ depending on HF stage.

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This paper presents the results of the analysis of resistive switching properties observed in a Au/(Ti-Cu)Ox/TiAlV structure with a gradient distribution of Cu and Ti along the (Ti-Cu)Ox thin film thickness. Thin films were prepared via multisource reactive magnetron co-sputtering. The programmed profile of the pulse width modulation coefficient during sputtering of the Cu target allowed us to obtain the designed gradient U-shape profile of the Cu concentration in the deposited thin film. Electrical measurements of the Au/(Ti-Cu)Ox/TiAlV structure showed the presence of nonpinched hysteresis loops in the voltage-current plane testifying a resistive switching behavior. Results of optical, X-ray, and ultraviolet photoelectron spectroscopy measurements allowed us to elaborate the scheme of the bandgap alignment of the prepared thin films with respect to the Au and TiAlV electrical contacts. Detailed structure and elemental profile investigations allowed us to conclude about the possible mechanism for the observed resistive switching mechanism.

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In this work, selected properties of metallic and oxide thin films based on titanium and cobalt were described. Thin-film coatings were prepared using the magnetron sputtering method. The deposition was carried out from sintered targets with different Co-content (2 at.%, 12 at.% and 50 at.%). The relation between the Ti-Co target composition and the Co-content in the metallic and oxide films was examined. There was 15-20% more cobalt in the films than in the target. Moreover, the deposition rate under neutral conditions (in Ar plasma) was even 10-times higher compared to oxidizing Ar:O2 (70:30) plasma. A comprehensive analysis of the structural properties (performed with GIXRD and SEM) revealed the amorphous nature of (Ti,Co)Ox coatings, regardless of the cobalt content in the coating. The fine-grained, homogenous microstructure was observed, where cracks and voids were identified only for films with high Co-content. Optical studies have shown that these films were well transparent (60% ÷ 80%), and the amount of cobalt in the target from which they were sputtered had a significant impact on the decrease in the transparency level, the slight shift of the absorption edge position (from 279 nm to 289 nm) as well as the decrease in their optical band gap energy (from 3.13 eV to 1.71 eV). Electrical studies have shown that in (Ti,Co)Ox thin films, a unipolar memristive-like effect can be observed. The occurrence of such effects has not been reported so far in the case of TiO2 coatings with the addition of Co.

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BACKGROUND: The determinants of the impact of mineralocorticoid receptor antagonism (MRA) on exercise tolerance in heart failure with reduced ejection fraction (HFrEF) have not been sufficiently characterised. AIM: We sought to investigate the factors associated with improvement in exercise capacity following the introduction of spironolactone to therapy in HFrEF patients, as well as to assess the association between improvement in exercise capacity and changes in cardiac functional characteristics with treatment. METHODS: In 120 patients (age 62 ± 11 years) with stable chronic HFrEF, remaining on optimal pharmacotherapy, spironolactone 25 mg/d was added to treatment. Echocardiographic assessment, including myocardial deformation, and treadmill exercise tests were performed at baseline and at six-month follow-up. RESULTS: According to the functional improvement at follow-up, patients were stratified into two groups: with increase in exercise capacity > 20% (IMPRpos, n = 68) and < 20% (IMPRneg, n = 52) of the baseline value. The IMPRpos subset demonstrated significantly larger improvement in left ventricular systolic and diastolic functions at follow-up, as assessed by global longitudinal deformation (GLS), ejection fraction, and tissue e' velocity. Functional improvement > 20% was independently predicted by diabetes (odds ratio [OR] 5.62, p = 0.011), estimated glomerular filtration rate (OR 0.95, p = 0.008), and B-type natriuretic peptide (BNP) at baseline (OR 0.54, p = 0.027), and associated with increase in GLS at follow-up (OR 1.40, p = 0.019). CONCLUSIONS: In patients with HFrEF, improvement in exercise capacity in response to the addition of spironolactone to treatment is more evident in the presence of diabetes, decreased renal function and lower BNP, and improvement in GLS is a contributor to this beneficial effect of MRA.

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OBJECTIVE: Apelin--a novel multifunction peptide implicated in regulation of the cardiovascular system, including blood pressure and cardiac function control - has been postulated to be involved in the pathophysiology of hypertension and hypertensive heart disease. We investigated the circulating apelin level and its relationship to left ventricular function in patients with essential hypertension. METHODS: We enrolled 232 hypertensive patients without concomitant diseases affecting cardiovascular functions and 76 healthy controls. Each patient underwent plasma apelin measurement and echocardiographic assessment of left ventricular systolic and diastolic function using myocardial velocities and deformation parameters, and myocardial reflectivity using calibrated integrated backscatter. RESULTS: Hypertensive patients demonstrated lower plasma apelin than the controls (265 ± 127 vs. 330 ± 159 pg/ml; P<0.001). Patients with the lowest plasma apelin, that is, from the first tertile, exhibited more severe left ventricular systolic and diastolic function abnormalities than their peers from the other two tertiles. In multivariable regression analysis, apelin was, in addition to patient age, BMI, blood pressure, left ventricular mass index and calibrated integrated backscatter in the basal septum, an independent correlate of left ventricular systolic function parameters (ß=0.18; P<0.001 for strain and ß=0.12; P<0.03 for systolic strain rate) and diastolic function parameters (ß=0.13; P<0.01 for early diastolic strain rate, ß=0.11; P<0.04 for early diastolic myocardial velocity, and ß=-0.11; P<0.04 for the ratio of mitral inflow to mitral annular early diastolic velocity). CONCLUSION: In patients with essential hypertension, circulating apelin levels are reduced, and lower plasma apelin is independently associated with more profound left ventricular systolic and diastolic function impairment.

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Pulmonary artery aneurysm (PAA) is an uncommon lesion, which may be associated with different etiologies including congenital cardiovascular diseases, systemic vasculitis, connective tissue diseases, infections, and trauma. Idiopathic PAA is sporadically diagnosed by exclusion of concomitant major pathology. We report a case of a 56-year-old female with an idiopathic pulmonary artery dilatation identified fortuitously by echocardiography and confirmed by contrast-enhanced computed tomography. Neither significant pulmonary valve dysfunction nor pulmonary hypertension and other cardiac abnormalities which might contribute to the PAA development were found. Here, we describe echocardiographic and computed tomography findings and review the literature on PAA management.

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