Biological carbon capture from biogas streams: Insights into Cupriavidus necator autotrophic growth and transcriptional profile.

Recycling carbon-rich wastes into high-value platform chemicals through biological processes provides a sustainable alternative to petrochemicals. Cupriavidus necator, known for converting carbon dioxide (CO2) into polyhydroxyalkanoates (PHA) was studied for the first time using biogas streams as the sole carbon source. The bacterium efficiently consumed biogenic CO2 from raw biogas with methane at high concentrations (50%) proving non-toxic. Continuous addition of H2 and O2 enabled growth trends comparable to glucose-based heterotrophic growth. Transcriptomic analysis revealed CO2-adaptated cultures exhibited upregulation of hydrogenases and Calvin cycle enzymes, as well as genes related to electron transport, nutrient uptake, and glyoxylate cycle. Non-adapted samples displayed activation of stress response mechanisms, suggesting potential lags in large-scale processes. These findings showcase the setting of growth parameters for a pioneering biological biogas upgrading strategy, emphasizing the importance of inoculum adaptation for autotrophic growth and providing potential targets for genetic engineering to push PHA yields in future applications.

Changes in echocardiographic parameters over time in paradoxical low-flow low-gradient aortic stenosis.

AIMS: To assess the progression of the disease and evolution of the main echocardiographic variables for quantifying AS in patients with severe low-flow low-gradient (LFLG) AS compared to other severe AS subtypes. METHODS AND RESULTS: Longitudinal, observational, multicenter study including consecutive asymptomatic patients with severe AS (aortic valve area, AVA < 1.0 cm²) and normal left ventricle ejection fraction (LVEF ≥ 50%). Patients were classified according to baseline echocardiography into: HG (high gradient; mean gradient ≥ 40 mmHg), NFLG (normal-flow low-gradient; mean gradient < 40 mmHg, indexed systolic volume (SVi) > 35mL/m2), or LFLG (mean gradient < 40 mmHg, SVi ≤ 35 mL/m²). AS progression was analyzed by comparing patients' baseline measurements and their last follow-up measurements or those taken prior to aortic valve replacement (AVR). Of the 903 included patients, 401 (44.4%) were HG, 405 (44.9%) NFLG, and 97 (10.7%) LFLG. Progression of the mean gradient in a linear mixed regression model was greater in low-gradient groups: LFLG vs. HG (regression coefficient 0.124, P = 0.005) and NFLG vs. HG (regression coefficient 0.068, P = 0.018). No differences were observed between the LFLG and NFLG groups (regression coefficient 0.056, P = 0.195). However, AVA reduction was slower in the LFLG group compared to the NFLG (P < 0.001). During follow-up, in conservatively-managed patients, 19.1% (n = 9) of LFLG patients evolved to having NFLG AS and 44.7% (n = 21) to having HG AS. In patients undergoing AVR, 58.0% (n = 29) of LFLG baseline patients received AVR with a HG AS. CONCLUSION: LFLG AS shows an intermediate AVA and gradient progression compared to NFLG and HG AS. The majority of patients initially classified as having LFLG AS changed over time to having other severe forms of AS, and most of them received AVR with a HG AS.

Unraveling prevalence of homoacetogenesis and methanogenesis pathways due to inhibitors addition.

Three inhibitors targeting different microorganisms, both from Archaea and Bacteria domains, were evaluated for their effect on CO2 biomethanation: sodium ionophore III (ETH2120), carbon monoxide (CO), and sodium 2-bromoethanesulfonate (BES). This study examines how these compounds affect the anaerobic digestion microbiome in a biogas upgrading process. While archaea were observed in all experiments, methane was produced only when adding ETH2120 or CO, not when adding BES, suggesting archaea were in an inactivated state. Methane was produced mainly via methylotrophic methanogenesis from methylamines. Acetate was produced at all conditions, but a slight reduction on acetate production (along with an enhancement on CH4 production) was observed when applying 20 kPa of CO. Effects on CO2 biomethanation were difficult to observe since the inoculum used was from a real biogas upgrading reactor, being this a complex environmental sample. Nevertheless, it must be mentioned that all compounds had effects on the microbial community composition.

Prognosis of Paradoxical Low-Flow Low-Gradient Aortic Stenosis: A Severe, Non-critical Form, With Surgical Treatment Benefits.

Objectives: To determine the risk of mortality and need for aortic valve replacement (AVR) in patients with low-flow low-gradient (LFLG) aortic stenosis (AS). Methods: A longitudinal multicentre study including consecutive patients with severe AS (aortic valve area [AVA] < 1.0 cm2) and normal left ventricular ejection fraction (LVEF). Patients were classified as: high-gradient (HG, mean gradient ≥ 40 mmHg), normal-flow low-gradient (NFLG, mean gradient < 40 mmHg, indexed systolic volume (SVi) > 35 ml/m2) and LFLG (mean gradient < 40 mmHg, SVi ≤ 35 ml/m2). Results: Of 1,391 patients, 147 (10.5%) had LFLG, 752 (54.1%) HG, and 492 (35.4%) NFLG. Echocardiographic parameters of the LFLG group showed similar AVA to the HG group but with less severity in the dimensionless index, calcification, and hypertrophy. The HG group required AVR earlier than NFLG (p < 0.001) and LFLG (p < 0.001), with no differences between LFLG and NFLG groups (p = 0.358). Overall mortality was 27.7% (CI 95% 25.3-30.1) with no differences among groups (p = 0.319). The impact of AVR in terms of overall mortality reduction was observed the most in patients with HG (hazard ratio [HR]: 0.17; 95% CI: 0.12-0.23; p < 0.001), followed by patients with LFLG (HR: 0.25; 95% CI: 0.13-0.49; p < 0.001), and finally patients with NFLG (HR: 0.29; 95% CI: 0.20-0.44; p < 0.001), with a risk reduction of 84, 75, and 71%, respectively. Conclusions: Paradoxical LFLG AS affects 10.5% of severe AS, and has a lower need for AVR than the HG group and similar to the NFLG group, with no differences in mortality. AVR had a lower impact on LFLG AS compared with HG AS. Therefore, the findings of the present study showed LFLG AS to have an intermediate clinical risk profile between the HG and NFHG groups.

Combined Therapeutics for Atherosclerosis Treatment Using Polymeric Nanovectors.

Atherosclerosis is an underlying risk factor in cardiovascular diseases (CVDs). The combination of drugs with microRNAs (miRNA) inside a single nanocarrier has emerged as a promising anti-atherosclerosis strategy to achieve the exploitation of their complementary mechanisms of action to achieve synergistic therapeutic effects while avoiding some of the drawbacks associated with current systemic statin therapies. We report the development of nanometer-sized polymeric PLGA nanoparticles (NPs) capable of simultaneously encapsulating and delivering miRNA-124a and the statin atorvastatin (ATOR). The polymeric NPs were functionalized with an antibody able to bind to the vascular adhesion molecule-1 (VCAM1) overexpressed in the inflamed arterial endothelium. The dual-loaded NPs were non-toxic to cells in a large range of concentrations, successfully attached overexpressed VCAM receptors and released the cargoes in a sustainable manner inside cells. The combination of both ATOR and miRNA drastically reduced the levels of proinflammatory cytokines such as IL-6 and TNF-α and of reactive oxygen species (ROS) in LPS-activated macrophages and vessel endothelial cells. In addition, dual-loaded NPs precluded the accumulation of low-density lipoproteins (LdL) inside macrophages as well as morphology changes to a greater extent than in single-loaded NPs. The reported findings validate the present NPs as suitable delivery vectors capable of simultaneously targeting inflamed cells in atherosclerosis and providing an efficient approach to combination nanomedicines.

New insights of tricuspid regurgitation: a large-scale prospective cohort study.

AIMS: To evaluate the burden of tricuspid regurgitation (TR) in a large cohort, determine the right ventricle involvement of patients with TR and determine the characteristics of isolated TR. METHODS AND RESULTS: Prospective study where consecutive patients undergoing an echocardiographic study in 10 centres were included. All studies with significant TR (at least moderate) were selected. We considered that patients with one of pulmonary systolic hypertension >50 mmHg, left ventricular ejection fraction <35%, New York Heart Association III-IV, or older than 85 years, had a high surgical risk. A total of 35 088 echocardiograms were performed. Significant TR was detected in 6% of studies. Moderate TR was found in 69.6%, severe in 25.5%, massive in 3.9%, and torrential in 1.0% of patients. Right ventricle was dilated in 81.7% of patients with massive/torrential TR, in 55.9% with severe TR, and in 29.3% with moderate TR (P < 0.001). Primary TR was present in 7.4% of patients whereas secondary TR was present in 92.6%. Mitral or aortic valve disease was the most common aetiology (54.6%), following by isolated TR (16%). Up to 51.9% of patients with severe, massive, or torrential primary TR and 57% of patients with severe, massive, or torrential secondary TR had a high surgical risk. CONCLUSION: Significant TR is a prevalent condition and a high proportion of these patients have an indication for valve intervention. More than a half of patients with severe, massive, or torrential TR had a high surgical risk. Massive/torrential TR may have implications regarding selection and monitoring patients for percutaneous treatment.

A mathematical approach to predict the solids concentration in anaerobic membrane bioreactos (AnMBR): Evaluation of the volatile solids solubilization.

Anaerobic Membrane Bioreactors (AnMBR) are gaining attention as a suitable approach for sustainable low-strength wastewater treatment, as they bring together the advantages of both anaerobic treatments and membrane bioreactors. However, increasing the sludge retention time (SRT) necessary to favor hydrolysis increases the suspended solids concentration potentially leading to decreased permeate flux. Therefore, the availability of a mathematical approach to predict the solids concentration within an AnMBR can be very useful. In this work, a mathematical model describing the volatile solids concentration within the reactor as a function of the operating parameters and the influent characteristics is developed. The solubilization of organic particulates was clearly influenced by temperature and the SRT, whereas the hydraulic retention time influence was negligible. Furthermore, the activation energy value of about 20 kJ mol-1 confirms the idea that diffusion of hydrolytic enzymes from the bulk solution to the particle surface is the rate-limiting step of hydrolysis.

New frontiers from removal to recycling of nitrogen and phosphorus from wastewater in the Circular Economy.

Nutrient recovery technologies are rapidly expanding due to the need for the appropriate recycling of key elements from waste resources in order to move towards a truly sustainable modern society based on the Circular Economy. Nutrient recycling is a promising strategy for reducing the depletion of non-renewable resources and the environmental impact linked to their extraction and manufacture. However, nutrient recovery technologies are not yet fully mature, as further research is needed to optimize process efficiency and enhance their commercial applicability. This paper reviews state-of-the-art of nutrient recovery, focusing on frontier technological advances and economic and environmental innovation perspectives. The potentials and limitations of different technologies are discussed, covering systems based on membranes, photosynthesis, crystallization and other physical and biological nutrient recovery systems (e.g. incineration, composting, stripping and absorption and enhanced biological phosphorus recovery).

Triggered RNAi Therapy Using Metal Inorganic Nanovectors.

The administration of small interfering RNA (siRNA) is a very interesting therapeutic option to treat genetic diseases such as Alzheimer's or some types of cancer, but its effective delivery still remains a challenge. Herein, Au nanorod (GNR)-based platforms functionalized with polyelectrolyte layers were developed and analyzed as potential siRNA nanocarriers. The polymeric layers were successfully assembled on the particle surfaces by means of the layer-by-layer assembly technique through the alternating deposition of oppositely charged poly(styrene)sulfonate, PSS, poly(lysine), PLL, and siRNA biopolymers, with a final hyaluronic acid layer in order to provide the nanoconstructs with a potential targeting ability as well as colloidal stability in physiological medium. Once the hybrid nanocarriers were obtained, the cargo release, their colloidal stability in physiological-relevant media, cytotoxicity, cellular internalization and uptake, and knockdown activity were studied. The present hybrid particles release the genetic material inside cells by means of a protease-assisted and/or a light-triggered release mechanism in order to control the delivery of the oligonucleotides on demand. In addition, the hybrid nanovectors were observed to be nontoxic to cells and could efficiently deliver the genetic material in the cell cytoplasms. The GNR-based nanocarriers proposed here can provide a suitable environment to load and protect a sufficient amount of the genetic material to allow an efficient and sustained knockdown gene expression for long (up to 93% for 72 h), thanks to the slow degradation of PLL, without the observation of adverse side toxic effects. It was also found that the silencing activity was enhanced with the number of siRNA layers assembled in the nanoplatforms.

Assessment of cross-flow filtration as microalgae harvesting technique prior to anaerobic digestion: Evaluation of biomass integrity and energy demand.

In the present study, the effect of cross-flow filtration (CFF) on the overall valorization of Chlorella spp. microalgae as biogas was assessed. The effect of CFF on microalgae cell integrity was quantified in terms of viability which was correlated with the anaerobic biodegradability. The viability dropped as the biomass concentration increased, whereas anaerobic biodegradability increased linearly with the viability reduction. It was hypothesized that a stress-induced release and further accumulation of organic polymers during CFF increased the flux resistance which promoted harsher shear-stress conditions. Furthermore, the volume reduction as the concentration increased entailed an increase in the specific energy supply to the biomass. The energy demand was positive in the whole range of concentrations studied, yielding an overall energy efficiency as high as 22.9% for the highest concentration studied. Specifically, heat requirements were lower than electricity requirements only when the biomass concentrations exceeded 10 g COD·L-1.

Large-scale assessment of aortic stenosis: facing the next cardiac epidemic?

Aims: Aortic stenosis (AS) is the most frequent valvular disease in developed countries. As society grows older, the prevalence of AS increases. However, the real burden, current aetiology, severity distribution, and echocardiographic patterns of AS are not fully clear. The aim of the present study is to provide an accurate overall picture of AS, focusing on its epidemiology, aetiology, and echocardiographic features. Methods and results: A total of 29 502 consecutive echocardiograpies were prospectively included in this multicentre study. The present sample was composed of patients with advanced age (mean 75.2 years) and similar gender distribution. High proportion (7.2%) showed any grade of AS, with important number of patients (2.8%) presenting severe AS, most of them aged 75 years or more. Coexisting valvular disease appeared in almost half of the sample (49.6%), being the most frequently diagnosed aortic regurgitation (AR) (22%) followed by mitral regurgitation (MR) (15.6%). Degenerative aetiology was found in the vast majority (93.4%) of the studies whereas rheumatic is currently infrequent (3.35%). Low flow-low gradient (LFLG) appeared in 24.6% of patients with severe AS. Atrial fibrillation (23.1% vs. 11.6%; P = 0.002), MR (23.3% vs. 15.1%; P = 0.018), and right ventricle dysfunction (13.3% vs. 5.2%; P = 0.003) appeared frequently in LFLG group. Conclusions: Burden of AS is higher than previously assumed. Degenerative aetiology is the main cause of AS. Most of the patients are elder with high prevalence of significant co-existing valvular disease. LFLG severe AS is present in an important proportion of patients, showing high grade of left ventricle remodelling.

Alkylphenols and polycyclic aromatic hydrocarbons in eastern Mediterranean Spanish coastal marine bivalves.

This paper reports the first results on alkylphenol pollution in edible bivalves from the Spanish coast. Two sampling campaigns (July 2006 and July 2007) were carried out to determine the concentration of nonylphenol (NP), octylphenol (OP), and eight polycyclic aromatic hydrocarbons (PAHs) in wild mussels (Mytilus galloprovincialys) and clams (Donax trunculus) at 14 sampling sites along the eastern Mediterranean Spanish coast. The results show that NP is the predominant alkylphenol, being the port of Valencia the most polluted area (up to 147 µg/kg wet weight in clams). Moving away from the ports the concentration of NP in bivalves decreased. OP concentration was below its detection limit in most of the studied areas and its maximum concentration (6 µg/kg w/w) was measured in clams from the port of Sagunto. The presence of low levels of PAHs was observed in most of the studied areas. The total PAHs concentration (i.e., sum of the eight measured PAHs) achieved a maximum value of 10.09 µg/kg w/w in the north coast of Valencia city. The distribution pattern of the individual PAHs showed that both pollution sources petrogenic and pyrolytic were present in the sampled areas. Fluoranthene was the most abundant PAH in mussels while benzo(b)fluoranthene in clams. The maximum concentration of 10 µg/kg w/w for benzo(a)pyrene established by the European Commission was never reached, indeed sampled bivalves showed concentrations 10 times lower than this reference value. Thus, they can be considered safe for human consumption. Despite the low contamination levels, the results show an overall pollution of bivalves by alkylphenol and PAHs as well as an increment in the number of polluted areas from 2006 to 2007. Thus, periodical sampling campaigns should be carried out to monitor the long-term tendency of these toxic and persistent pollutants.

Ecocardiograma de esfuerzo para la evaluación de la enfermedad coronaria / Assessment of coronary artery disease by exercise echocardiography

La ecocardiografía de esfuerzo consiste en la adición de la imagen ecocardiográfica a la prueba de esfuerzo convencional. Tiene un perfil de seguridad, costo, rentabilidad diagnóstica y pronóstica y ausencia de radiación óptimos para la evaluación no invasiva de la enfermedad coronaria. Aparte de su valor indudable en casos de ECG basal no interpretable o en pacientes con resultado no concluyente en la prueba de esfuerzo convencional, las guías recientes la establecen como una alternativa diagnóstica y pronóstica a la prueba de esfuerzo convencional en los centros en que existan facilidades para ello. Su sensibilidad puede incrementarse si se entrena en la adquisición de imagen en pico de ejercicio, en lugar de la imagen posejercicio. Las limitaciones de antaño debidas a una deficiente ventana ecocardiográfica se han solventado en gran medida con el uso de la imagen armónica y el contraste para detección de bordes. La nueva tecnología es prometedora. Particularmente la eco 3D podría tener su papel al poder realizar un estudio completo en sólo unos segundos. Por otra parte, el strain bidimensional (speckle) puede medir el movimiento de torsión miocárdico que está abolido en situaciones de isquemia.

Ecocardiograma de esfuerzo para la evaluación de la enfermedad coronaria / Assessment of coronary artery disease by exercise echocardiography

La ecocardiografía de esfuerzo consiste en la adición de la imagen ecocardiográfica a la prueba de esfuerzo convencional. Tiene un perfil de seguridad, costo, rentabilidad diagnóstica y pronóstica y ausencia de radiación óptimos para la evaluación no invasiva de la enfermedad coronaria. Aparte de su valor indudable en casos de ECG basal no interpretable o en pacientes con resultado no concluyente en la prueba de esfuerzo convencional, las guías recientes la establecen como una alternativa diagnóstica y pronóstica a la prueba de esfuerzo convencional en los centros en que existan facilidades para ello. Su sensibilidad puede incrementarse si se entrena en la adquisición de imagen en pico de ejercicio, en lugar de la imagen posejercicio. Las limitaciones de antaño debidas a una deficiente ventana ecocardiográfica se han solventado en gran medida con el uso de la imagen armónica y el contraste para detección de bordes. La nueva tecnología es prometedora. Particularmente la eco 3D podría tener su papel al poder realizar un estudio completo en sólo unos segundos. Por otra parte, el strain bidimensional (speckle) puede medir el movimiento de torsión miocárdico que está abolido en situaciones de isquemia.(AU)

Assessment of diastolic function during exercise echocardiography: annulus mitral velocity or transmitral flow pattern?

OBJECTIVES: We hypothesize that the change in the left ventricular (LV) diastolic pattern (DP) may be measured with high reproducibility and correlates with exercise echocardiography (EE) better than the ratio of early LV inflow velocity to early diastolic annulus velocity (E/e' index). BACKGROUND: The E/e' index has been related to LV filling pressures but has not been compared with DP. METHODS: We selected 179 consecutive patients who were referred for EE. Early (E) and late (A) LV inflow velocities by conventional pulsed Doppler, and septal annulus e' velocity by pulsed Doppler myocardial imaging were measured at rest (R) and post-exercise (PE). RESULTS: Four LV-DPs were found: abnormal relaxation (AR) at R and PE (E < A) in 110 patients; AR at PE (E > A at R; E < A at PE) in 22 patients; restrictive pattern (RP) at R and PE (E > A) in 18 patients; and RP at PE (E < A at R; E > A at PE) in 29 patients. The more accurate PE cutoff E/e' values to predict abnormal EE, ischemic response, poor functional capacity (< 8 Mets in men; < 6 Mets in women), and lack of increase in left ventricular ejection fraction (LVEF) were 12, 12, 11, and 11 (areas under the curve were 0.53, 0.53, 0.63, and 0.57, respectively). Corresponding areas under the curve for an RP at R + PE or only at PE were 0.57, 0.55, 0.54, and 0.56 (P = not significant). The sensitivity of an RP at R + PE or only at PE was lower and the specificity was higher than those of the different E/e' cutoff values for predicting abnormal EE, functional capacity, ischemic response, and lack of increase in LVEF. Achieved Mets were lower in patients with an RP at R + PE or only at PE irrespectively of the E/e' values, whereas achieved Mets in patients with AR at R + PE or only at PE were lower if the E/e' was > or = 11 (8.2 +/- 2.9 vs. 9.8 +/- 3.1, P = .01). Interobserver and intraobserver concordance were 95% (kappa = 0.86) and 100% (kappa = 1.0) for an RP, and 86% (kappa = 0.73) and 92% (kappa = 0.78) for a PE-E/e' value of > or = 11. CONCLUSIONS: E/e' does not allow further stratification in patients with exercise RP. We propose both measurement of E/e' and determination of the LV-DP (a quickly assessable variable) for the assessment of diastolic function during EE. However, when an RP persists or develops with exercise, further assessment may not be more informative.

Global left ventricular systolic function based on the sum of regional myocardial velocities during exercise echocardiography.

OBJECTIVES: We sought to assess the relationship between global Doppler myocardial imaging (DMI) and left ventricular (LV) ejection fraction (LVEF) at both rest and exercise. BACKGROUND: We have previously demonstrated that global DMI correlates with LVEF at rest with low variability. METHODS: LVEF by 2-dimensional echocardiography, systolic global tissue Doppler velocity (s-TDV), strain (S) rate (SR), and S were assessed in 122 patients. LVEF was measured at rest and at peak exercise, whereas DMI was performed at rest and immediately postexercise. The region of interest by color DMI was set to enclose the external myocardial border when the LV achieved its maximal dimension. The means of the DMI assessments in the 4- and 2-chamber apical views at rest and postexercise were measured to correlate with LVEF. RESULTS: Significant correlations were found between the LVEF and global s-TDV, SR, and S either at rest (r = 0.32, r = 0.50, and r = 0.33, all P < .001) or at exercise (r = 0.47, r = 0.63, and r = 0.40, all P < .001). The best differentiation of an abnormal from a normal LVEF (>or=50%) at rest was provided by s-TDV less than 1.8 cm/s (sensitivity 63%, specificity 78%, area under the curve [AUC] 0.76, confidence interval [CI] 0.63-0.90), SR greater than -0.50/s (sensitivity 90%, specificity 76%, AUC 0.86, CI 0.76-0.97), and S greater than -9% (sensitivity 83%, specificity 75%, AUC 0.81, CI 0.70-0.91); whereas at exercise it was provided by s-TDV less than 3.5 cm/s (sensitivity 75%, specificity 74%, AUC 0.79, CI 0.69-0.89), SR greater than -0.80/s (sensitivity 83%, specificity 81%, AUC 0.91, CI 0.86-0.96), and S greater than -11% (sensitivity 67%, specificity 69%, AUC 0.74, CI 0.63-0.85). CONCLUSIONS: Global DMI is a valuable tool to assess global LV function during exercise.

Relation of left ventricular chamber stiffness at rest to exercise capacity in hypertrophic cardiomyopathy.

The degree of exercise capacity is poorly predicted by conventional markers of disease severity in patients with hypertrophic cardiomyopathy (HC). The principal mechanism of exercise intolerance in patients with HC is the failure of stroke volume augmentation due to left ventricular (LV) diastolic dysfunction. The role of LV chamber stiffness, assessed noninvasively, as a determinant of exercise tolerance is unknown. Sixty-four patients with HC were studied with Doppler echocardiography, exercise testing, and gadolinium cardiac magnetic resonance. The LV chamber stiffness index was determined as the ratio of pulmonary capillary wedge pressure (derived from the E/Ea ratio) to LV end-diastolic volume (assessed by cardiac magnetic resonance). Maximal exercise tolerance was defined as achieved METs. There were inverse correlations between METs achieved and age (r = -0.38, p = 0.003), heart rate deficit (r = -0.39, p = 0.002), LV outflow tract gradient (r = -0.33, p = 0.009), the E/Ea ratio (r = -0.4, p = 0.001), mean LV wall thickness (r = -0.26, p = 0.04), and LV stiffness (r = -0.56, p <0.001) and a positive correlation between METs achieved and LV end-diastolic volume (r = 0.33, p = 0.01). On multivariate analysis, only LV chamber stiffness was associated with exercise capacity. A LV stiffness level of 0.18 mm Hg/ml had 100% sensitivity and 75% specificity (area under the curve 0.84) for predicting < or =7 METs achieved. In conclusion, LV diastolic dysfunction at rest, as manifested by increased LV chamber stiffness, is a major determinant of maximal exercise capacity in patients with HC.

[Value of resting and exercise mitral regurgitation during exercise echocardiography to predict outcome in patients with left ventricular dysfunction]. / Valor pronóstico de la regurgitación mitral en reposo y ejercicio durante la ecocardiografía de ejercicio en pacientes con disfunción ventricular izquierda.

INTRODUCTION AND OBJECTIVES: The relative value of exercise echocardiography (EE) over resting echocardiography when this last incorporates information on mitral regurgitation (MR) is unknown. Furthermore, limited data exists regarding to the value of MR worsening during exercise in patients with LV dysfunction. We investigated whether: a) EE has incremental value over a resting echo-Doppler study; and b) post-exercise MR increments the value of EE for predicting outcome in patients with LV dysfunction. METHODS: 388 consecutive patients with LV dysfunction (LV ejection fraction <50%) were followed for 2.1 (1.5) years. There were 46 hard events (myocardial infarction in 10 and cardiac death in 36). RESULTS: There were 43 events in 319 patients with abnormal EE vs 3 events in 69 patients with normal EE (13% vs 4%, P=.04), whereas there were 20 events in the 103 patients with at least moderate resting MR vs 26 events in the 288 with no/mild MR (19% vs 9%, P=.006). Resting MR, peak heart rate x blood pressure, and n masculine of diseased territories on EE were independently associated to hard events. The same variables and MR worsening were independently associated to cardiac death. CONCLUSIONS: EE maintains its higher prognostic value over resting echocardiography even when this last incorporates information on MR. MR worsening increments the value of EE for predicting cardiac death in patients with LV dysfunction.

Valor pronóstico de la regurgitación mitral en reposo y ejercicio durante la ecocardiografía de ejercicio en pacientes con disfunción ventricular izquierda / Value of resting and exercise mitral regurgitation during exercise echocardiography to predict outcome in patients with left ventricular dysfunction

Introducción y objetivos. El valor relativo de la ecocardiografía de ejercicio (EE) sobre la ecocardiografía basal cuando esta última incorpora información sobre la regurgitación mitral (RM) es desconocido. Además, hay poca información sobre el valor del empeoramiento de la RM durante el ejercicio en pacientes con disfunción ventricular. El objetivo fue investigar: a) si la EE incrementa el valor pronóstico de la ecocardiografía Doppler basal, y b) si la RM posterior al ejercicio incrementa el valor pronóstico de la EE en pacientes con disfunción ventricular. Métodos. Se realizó el seguimiento de un grupo de 388 pacientes consecutivos con disfunción ventricular durante 2,1 ± 1,5 años. Hubo 46 eventos (infarto de miocardio en 10 y muerte cardiaca en 36). Resultados. Hubo 43 eventos en 319 pacientes con EE anormal frente a 3 eventos en 69 pacientes con EE normal (el 13 frente al 4%; p = 0,04), mientras que hubo 20 eventos en 103 pacientes con RM ≥ moderada basal frente a 26 eventos en los 288 con RM ligera o sin RM (el 19 frente al 9%; p = 0,006). La RM basal, el doble producto pico y el número de territorios afectos en la EE estaban independientemente asociados con eventos. Las mismas variables junto con el empeoramiento de la RM estaban independientemente asociadas con muerte cardiaca. Conclusiones. La EE mantiene su valor pronóstico sobre la ecocardiografía basal incluso cuando ésta incorpora información sobre la RM en pacientes con disfunción ventricular. El empeoramiento de la RM aumenta el valor predictivo de la EE para muerte cardiaca en pacientes con disfunción ventricular

Introduction and objectives. The relative value of exercise echocardiography (EE) over resting echocardiography when this last incorporates information on mitral regurgitation (MR) is unknown. Furthermore, limited data exists regarding to the value of MR worsening during exercise in patients with LV dysfunction. We investigated whether: a) EE has incremental value over a resting echo-Doppler study; and b) post-exercise MR increments the value of EE for predicting outcome in patients with LV dysfunction. Methods. 388 consecutive patients with LV dysfunction (LV ejection fraction <50%) were followed for 2.1 (1.5) years. There were 46 hard events (myocardial infarction in 10 and cardiac death in 36). Results. There were 43 events in 319 patients with abnormal EE vs 3 events in 69 patients with normal EE (13% vs 4%, P=.04), whereas there were 20 events in the 103 patients with at least moderate resting MR vs 26 events in the 288 with no/mild MR (19% vs 9%, P=.006). Resting MR, peak heart rate x blood pressure, and nº of diseased territories on EE were independently associated to hard events. The same variables and MR worsening were independently associated to cardiac death. Conclusions. EE maintains its higher prognostic value over resting echocardiography even when this last incorporates information on MR. MR worsening increments the value of EE for predicting cardiac death in patients with LV dysfunction

Prognostic value of mitral regurgitation assessment during exercise echocardiography in patients with known or suspected coronary artery disease.

BACKGROUND: Although mitral regurgitation (MR) may be assessed during exercise echocardiography (EE) there are no data regarding its value for predicting outcome in large series of patients. We sought to determine whether the predictive value of EE is maintained over clinical variables and resting echocardiography when the latter included information on MR, and to verify whether postexercise MR may improve the value of EE for predicting outcome. METHODS: In all, 1916 patients (mean age +/- 1SD = 62 +/- 11 years; mean left ventricular ejection fraction +/- 1SD = 56 +/- 11) referred for EE were followed up for 1.9 +/- 1.4 years. RESULTS: There were 87 cardiac events before revascularization: 67 events occurred in 948 patients with abnormal EE and 20 events occurred in 968 patients with normal EE (P < .0001), whereas there were 24 events in the 218 patients with moderate or higher resting MR and 63 events in the 1698 patients with no or mild MR (P < .0001). Previous myocardial infarction, resting MR, peak double product, and peak left ventricular ejection fraction were independently associated to hard events (chi2 model = 144, P < .0001). The same variables were associated to cardiac death (chi2 model = 141, P < .0001). Predictors of cardiac events in patients with abnormal EE were resting MR, resting wall-motion score index, metabolic equivalents, peak double product, and MR worsening (incremental P value of MR worsening = .03). Predictors of cardiac death were resting MR, peak double product, peak left ventricular ejection fraction, and MR worsening (incremental P value of MR worsening = .03). CONCLUSIONS: EE maintains its higher prognostic value over resting echocardiography even when the latter incorporates information on resting MR. MR worsening provides significant incremental prognostic information in patients with abnormal EE.