Search

Hypertension adds to the pressure overload on the left ventricle (LV) in combination with aortic valve (AV) disease, but the optimal blood pressure (BP) targets for patients with AV disease remain unclear. We tried to investigate whether intensive BP control reduces LV hypertrophy in asymptomatic patients with aortic stenosis (AS) or aortic regurgitation (AR). A total of 128 hypertensive patients with mild to moderate AS (n = 93) or AR (n = 35) were randomly assigned to intensive therapy, targeting a systolic BP <130 mm Hg, or standard therapy, targeting a systolic BP <140 mm Hg. The primary end point was the change in LV mass from baseline to the 24-month follow-up. Secondary end points included changes in severity of AV disease, LV volumes, ejection fraction and global longitudinal strain (GLS). The treatment groups were generally well balanced regarding the baseline characteristics. The mean (±SD) age of the patients was 68 ± 8 years and 48% were men. The mean BP was 145 ± 12/81 ± 10 mm Hg at baseline. Medication at baseline was similar between the 2 groups. The 2 treatment strategies resulted in a rapid and sustained difference in systolic BP (P <.05). At 24-month, the mean systolic BP was 129 ± 12 mm Hg in the intensive therapy group and 135 ± 14 mm Hg in the standard therapy group. No patient died or underwent AV surgery during follow-up in either of the groups. LV mass was changed from 189.5 ± 41.3 to 185.6 ± 41.5 g in the intensive therapy group (P =.19) and from 183.8 ± 38.3 to 194.0 ± 46.4 g in the standard therapy group (P <.01). The primary end point of change in LV mass was significantly different between the intensive therapy and the standard therapy group (-3.9 ± 20.2 g vs 10.3 ± 20.4 g; P =.0007). The increase in LV mass index was also significantly greater in the standard therapy group (P =.01). No significant differences in secondary end points (changes in severity of AV disease, LV volumes, ejection fraction and GLS) were observed between the treatment groups. Among hypertensive patients with AV disease, intensive hypertensive therapy resulted in a significant reduction in LV hypertrophy, although progression of AV disease was similar between the treatment groups. http://ClinicalTrials.gov (Number NCT03666351) Effects of Intensive Blood Pressure Control on Left Ventricular Hypertrophy in Aortic Valve Disease AR, Aortic regurgitation; AS, Aortic stenosis; AV, Aortic valve; BP, Blood pressure; HT, Hypertension; LV, left ventricle [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract A perfluorinated composite membrane incorporating an organic antioxidant was prepared to improve the chemical durability of a polymer electrolyte fuel cell. Bipyridine and benzoquinone (BQ) were added as organic antioxidants, and the oxidative stability of the composite electrolyte membranes containing them was evaluated via accelerated aging tests, i.e., an ex situ Fenton's test and in situ open-circuit voltage (OCV)-holding test. The effects of the antioxidants in the Fenton's test were verified using scanning electron microscopy, fluorine ion detection, Fourier-transform infrared spectroscopy, and tensile strength measurements. Moreover, a commercial membrane, NRE211, and a composite membrane, Nafion-BQ, were incorporated into a membrane electrode assembly (MEA) that then underwent an OCV-holding test for 500 h. The change in the MEA state over time was analyzed using cyclic voltammetry and linear sweep voltammetry. While NRE 211 showed a significant reduction in OCV from 300 h, Nafion-BQ maintained a stable OCV for 500 h. Hence, the organic antioxidants added to the electrolyte membrane effectively improved the oxidative stability of the proton exchange membrane fuel cell without sacrificing the ionic conductivity of the perfluorinated electrolyte membrane. Graphical abstract Image 1 Highlights • Organic antioxidants were introduced to perfluorinated polymer membrane. • No significant drop of proton conductivity & water uptake by organic antioxidants. • Chemical durability tests by ex-situ and in-situ accelerated tests. • Organic antioxidants improved the oxidative stability significantly. • The best antioxidant, BQ, was verified in the long-term OCV-holding test. [ABSTRACT FROM AUTHOR]

Atrial remodeling is known as an important pathophysiological changes in atrial fibrillation (AF). While there are many studies regarding importance of left atrial (LA) structural and functional changes in AF, little is known about the value of right atrial (RA) remodeling in this population. We investigated the prognostic value of indexed RA volume (RAVI) in patients with non-valvular atrial fibrillation. We assessed the relationship of RAVI with a composite outcome of hospitalization for heart failure (HF) or death in 258 consecutive patients (mean age=69±12years, male:female=168:90) with AF who performed two-dimensional echocardiography. Patients were excluded if they had significant intrinsic valvular heart disease, cardiomyopathies, left ventricular ejection fraction < 45%, severe renal failure requiring dialysis, pulmonary disease, or poor echocardiographic image. During a median follow-up of 3.6 years, 42 patients experienced clinical events, including 38 for HF hospitalization and 6 for death. In multivariable model after adjusting for clinical parameters and LVEF, RAVI was associated with increased risk of a primary composite outcome or and HF hospitalization alone as well as HF hospitalization alone (Adjusted HR=1.14 [95% CI 1.04-1.25] per 5 mL/m2 of RAVI for composite outcome, P =0.006; Adjusted HR=1.16 [95% CI 1.05-1.28] per 5 mL/m2 of RAVI for HF hospitalization, P =0.003). In contrast, indexed LA volume (LAVI) was not related to the primary composite outcome or HF alone (Adjusted HR=1.00 [95% CI 0.94-1.07] per 5 mL/m2 of LAVI for composite outcome, P =1.00; Adjusted HR=0.99 [95% CI 0.92-1.06] per 5 mL/m2 of LAVI for HF hospitalization, P =0.70). In patients with non-valvular AF, RAVI, but not LAVI, was predictive of HF hospitalization or mortality, suggesting that RA volume can be helpful in assessing future cardiovascular risk in this population. [ABSTRACT FROM AUTHOR]

Abstract: Uncharged porous PVDF and sulfonated porous PVDF membranes were prepared as alternative materials to Nafion membrane for application in a microbial fuel cell (MFC). Performances of Nafion, uncharged porous PVDF and sulfonated porous PVDF membranes in an air-cathode MFC were evaluated. Both uncharged and sulfonated porous PVDF membranes performed better than the Nafion membrane during MFC operation. The observed properties of low membrane electrical resistance, high ion exchange capacity, moderate oxygen permeability, and high ion selectivity also indicated that the sulfonated PVDF membrane is the most appropriate membrane for MFC applications. The uncharged porous PVDF membrane exhibited the lowest oxygen permeability resulting in a higher performance than the Nafion membrane. The impedance of the MFC systems was measured and analyzed with an equivalent circuit which accounts for the electrolyte (as media for microorganisms), both electrodes, and a membrane as components. It was found that the high performance of the sulfonated porous PVDF membrane is due to the low impedance of all components in the MFC. The sulfonated porous PVDF membrane, prepared for low resistance proton transport, is successfully applied to the MFC in this study. [Copyright &y& Elsevier]

Aims: The mechanisms responsible for the increased risk of heart failure (HF) post–myocardial infarction (MI) may differ between patients with versus without diabetes. We hypothesized that after high-risk MI, patients with diabetes would demonstrate patterns of remodeling that are suggestive of reduced ventricular compliance and that are associated with an increased risk of death or HF. Methods and Results: We performed quantitative echocardiographic analysis in 153 patients with diabetes and 451 patients without diabetes enrolled in the VALIANT Echo study. Diabetes was associated with a higher risk of death or HF in age-adjusted models (hazard ratio 1.44, 95% CI 1.04-2.00, P = .028). Diabetic patients were similar to nondiabetic patients with respect to left ventricular (LV) volume and ejection fraction but had higher LV mass index (104.1 ± 27.5 vs 97.1 ± 28.6 g/m2, P = .009), relative wall thickness (0.41 ± 0.08 vs 0.38 ± 0.07, P < .0001), and left atrial volume index (LAVi) (26.2 ± 8.1 vs 24.0 ± 8.2 mL/m2, P = .008)—all parameters that were significantly related to the risk of death or HF hospitalization. Changes in LV volume and ejection fraction from baseline to 20 months were not different, although diabetic patients demonstrated greater increase in LAVi (4.4 ± 7.7 vs 2.2 ± 6.7 mL/m2, P = .01). Conclusions: After high-risk MI, diabetic patients were at higher risk of death or HF and demonstrated greater baseline LV mass index, relative wall thickness, and LAVi as well as greater left atrial enlargement at 20-month follow-up. These findings suggest greater baseline concentric remodeling and long-term elevation in LV diastolic pressure post-MI among diabetic patients, which may partially mediate this risk. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study was to evaluate the safety and efficacy of combination treatment of rosuvastatin with ezetimibe in patients with primary hypercholesterolemia. Methods This multicenter, randomized, double-blind study comprised a main study and an extension study. In the main study, the efficacy and safety of a combination of rosuvastatin (5, 10, and 20 mg) with ezetimibe (10 mg) were compared with those of rosuvastatin (5, 10, and 20 mg) alone. The subjects who achieved the National Cholesterol Education Program Adult Treatment Panel III LDL-C goal in the main study and agreed to a further study were enrolled for the extension study. In the extension study, ezetimibe 10 mg was also administered to subjects who had received rosuvastatin (5, 10, and 20 mg) alone in the main study, and the same treatment was continued for subjects who had received a combination of rosuvastatin with ezetimibe in the main study. Findings At the end of the main study (week 8), LDL-C levels were significantly lower in subjects receiving combination therapy than in those receiving rosuvastatin monotherapy. Other lipid profiles also significantly improved in the combination therapy group. These improvements continued in the extension study. The combination therapy of rosuvastatin and ezetimibe was generally well tolerated. At the end of the main study, more subjects achieved the National Cholesterol Education Program Adult Treatment Panel III LDL-C goal in the combination therapy group than in the monotherapy group. The increased dosage of rosuvastatin was also well tolerated in the combination treatment. Implications Combination therapy of ezetimibe 10 mg with varying doses of rosuvastatin that are commonly used in the clinical field improved the lipid profile and allowed more subjects to reach the LDL-C goal in primary hypercholesterolemia compared with rosuvastatin monotherapy. In addition, the efficacy of the combination therapy was maintained for the extended period. Additional beneficial changes were also achieved with combination therapy even in patients who responded well to rosuvastatin monotherapy. ClinicalTrials.gov identifier: NCT03288038. [ABSTRACT FROM AUTHOR]

Background: Limited data exist to characterize novel measures of left atrial (LA) structure and function in older adults without prevalent heart failure (HF).Objectives: The aim was to assess reference range of LA measures, their associations with N-terminal pro-B-type natriuretic-peptide (NT-proBNP) and the related risk for incident HF or death.Methods: We analyzed LA structure (LA maximal [LAViMax] and minimal volume indexed by body surface area) and function (LA emptying fraction, LA reservoir, conduit, and contraction strain) in 4,901 participants from the ARIC (Atherosclerosis Risk In Communities) study (mean age 75 ± 5 years, 40% male, and 19% Black) without prevalent HF. We assessed sex-specific 10th and 90th percentile ARIC-based reference limits in 301 participants free of prevalent cardiovascular disease, and related LA measures to NT-proBNP and incident HF or death (median follow-up of 5.5 years) in the whole ARIC cohort.Results: Approximately 20% of the overall population had LA abnormalities according to the ARIC-based reference limit. Each LA measure was associated with NT-proBNP and, except for LAViMax, with incident HF or death after multivariable adjustment (including left ventricular function and NT-proBNP). Results were consistent in participants with normal LAViMax (P for interaction > 0.05). LA measures were prognostic for both incident HF with preserved ejection fraction or death and incident HF with reduced ejection fraction or death. When added to HF risk factors and NT-proBNP (baseline C-statistics = 0.74) all LA measures, except for LAViMax, significantly enhanced the prognostic accuracy.Conclusions: Novel measures of LA structure and function, but not standard assessment by LAViMax, are associated with increased risk of incident HF or death regardless of measures of left ventricular function and NT-proBNP. [ABSTRACT FROM AUTHOR]

Objectives: We sought to investigate the clinical prognostic value of longitudinal and circumferential strain (S) and strain rate (SR) in patients after high-risk myocardial infarction (MI). Background: Left ventricular (LV) contractile performance after MI is an important predictor of long-term outcome. Tissue deformation imaging might more closely reflect myocardial contractility than traditional measures of systolic functions. Methods: The VALIANT (Valsartan in Acute Myocardial Infarction Trial) Echo study enrolled 603 patients with LV dysfunction, heart failure, or both 5 days after MI. We measured global peak longitudinal S and systolic SR (SRs) from apical 4- and 2-chamber views and global circumferential S and SRs from parasternal short-axis view with speckle tracking software (Velocity Vector Imaging, Siemens, Inc., Mountain View, California). We related global S and SRs to LV remodeling at 20-month follow-up and to clinical outcomes. Results: Both longitudinal (mean: −5.1 ± 1.6 100/ms) and circumferential SRs (mean: −8.0 ± 2.8 100/ms) were predictive of death or hospital stay for heart failure (hazard ratio: 2.4, 95% confidence interval [CI]: 2.0 to 3.1, p < 0.001; hazard ratio: 1.3, 95% CI: 1.2 to 1.4, p < 0.001, respectively) after adjustment for clinical covariates by Cox proportional hazards, and longitudinal SRs further improved in predicting 18-month survivor on a model based on clinical and standard echocardiographic measures (increase in area under the receiver-operator characteristic curve: 0.13, p = 0.009). With multivariable logistic regression, circumferential SRs, but not longitudinal SRs, was strongly predictive of remodeling (odds ratio: 1.3, 95% CI: 1.1 to 1.4, p < 0.001). Conclusions: Both longitudinal and circumferential SRs were independent predictors of outcomes after MI, whereas only circumferential SRs was predictive of remodeling, suggesting that preserved circumferential function might serve to restrain ventricular enlargement after MI. [Copyright &y& Elsevier]