52 results on '"Monteagudo JM"'
Search Results
2. Poster Session 6Assessment of morphology and functionP1222Multimodality imaging for left atrial appendage occluder sizingP1223Longitudinal left atrial strain is a main predictor for long term prognosis on atrial fibrillation after CABG operation patientsP1224Comparison of 2D and 3D left ventricular volumes measurements: results from the SKIPOGH II studyP1225Adjusting for thoracic circumference is superior to body surface area in the assessment of neonatal cardiac dimensions in foetal growth abnormalityP1226Maximal vortex suction pressure: an equivocal marker for optimization of atrio-ventricular delayP1227Volume-time curve of cardiac magnetic resonance assessed left ventricular dysfunction in coronary artery disease patients with type 2 diabetes mellitusP1228Thickness matters, but not in the same way for all strain parametersP1229Digging deeper in postoperative modifications of right ventricular function: impact of pericardial approach and cardioplegiaP1230Left atrial function evaluated by 2D-speckle tracking echocardiography in diabetes mellitus populationP1231The influence of arterial hypertension duration on left ventricular diastolic parameters in patients with well regulated arterial blood pressureP1232Investigation of factors affecting left ventricular diastolic dysfunction determined using mitral annulus velocityP1233High regulatory T-lymphocytes after ST-elevation myocardial infarction relate with adverse left ventricular remodelling assessed by 3D-echocardiographyP1234Prevalence of paradoxical low flow/low gradient severe aortic stenosis measure with 3 dimensional transesophageal echocardiographyP1235Coronary microvascular and diastolic dysfunctions after aortic valve replacement: comparison between mechanical and biological prosthesesP1236Normal-flow, low gradient aortic stenosis is common in a population of patients with severe aortic valve stenosis undergoing aortic valve replacementP1237Analysis of validity and reproducibility of calcium burden visual estimation by echocardiographyP12383D full automatic software in the evaluation of aortic stenosis severity in TAVI patients. Preliminary resultsP1239Differential impact of net atrioventricular compliance on clinical outcomes in patients with mitral stenosis according to cardiac rhythmP1240Aortic regurgitation affects the intima-media thickness of the right and left common carotid artery differentlyP1241Global longitudinal strain: an hallmark of cardiac damage in mitral valve regurgitation. Experience from the european registry of mitral regurgitationP1242Echocardiographic characterisation of Barlow's disease versus fibroelastic deficiencyP1243Echocardiographic screening for rheumatic heart disease in a ugandan orphanage - feasibility and outcomesP1244Alterations in right ventricular mechanics upon follow-up period in patients with persistent ischemic mitral regurgitation after inferoposterior myocardial infarctionP1245Ten-years conventional mitral surgery in patients with mitral regurgitation and left ventricular dysfunction: clinical and echocardiographic outcomes
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Wassmuth, R., primary, Hristova, K., primary, Monney, P., primary, Olander, RFW, primary, Rodriguez Munoz, D., primary, Huayan, X., primary, Pagourelias, E., primary, Loardi, C., primary, Moreno, J., primary, Miljkovic, T., primary, Takase, H., primary, Latet, SC., primary, Henquin, R., primary, America, R., primary, Carter-Storch, R., primary, Panelo, ML., primary, Fernandez-Golfin, C., primary, Cho, IJ., primary, Petrini, J., primary, Buonauro, A., primary, Liu, B., primary, Mapelli, M., primary, Tamulenaite, E., primary, De Chiara, B., primary, Minden, H., additional, Kostova, V., additional, Nesheva, N., additional, Katova, TZ., additional, Bojadzhiev, L., additional, Crisinel, V., additional, Reverdin, S., additional, Conti, L., additional, Mach, F., additional, Mueller, H., additional, Jeanrenaud, X., additional, Bochud, M., additional, Ehret, G., additional, Sundholm, JKM, additional, Ojala, T., additional, Andersson, S., additional, Sarkola, T., additional, Moya Mur, JL., additional, Berlot, B., additional, Fernandez-Golfin, C., additional, Moreno Planas, J., additional, Casas Rojo, E., additional, Garcia Martin, A., additional, Jimenez Nacher, JJ., additional, Hernandez-Madrid, A., additional, Franco Diez, E., additional, Matia Frances, R., additional, Zamorano, JL., additional, Zhigang, YANG, additional, Yingkun, GUO, additional, Jing, CHEN, additional, Duchenne, J., additional, Mirea, O., additional, Triantafyllis, A., additional, Michalski, B., additional, Vovas, G., additional, Delforge, M., additional, Van Cleemput, J., additional, Bogaert, J., additional, Voigt, JU., additional, Saccocci, M., additional, Tamborini, G., additional, Veglia, F., additional, Pepi, M., additional, Alamanni, F., additional, Zanobini, M., additional, Zuniga Sedano, JJ., additional, Alexanderson, E., additional, Martinez, C., additional, Bjelobrk, M., additional, Pavlovic, K., additional, Ilic, A., additional, Colakovic, S., additional, Dodic, S., additional, Tanaka, T., additional, Machii, M., additional, Nonaka, D., additional, Van Herck, PL., additional, Claeys, MJ., additional, Haine, SE., additional, Miljoen, HP., additional, Segers, VF., additional, Vandendriessche, TR., additional, De Winter, BY., additional, Hoymans, VY., additional, Vrints, CJ., additional, Lombardero, M., additional, Perea, G., additional, Miele, MM., additional, De Amicis, DAV, additional, Mannacio, VAM, additional, Dahl, JS., additional, Christensen, NL., additional, Soendergaard, EV., additional, Marcussen, N., additional, Moeller, JE., additional, Fernandez-Palomeque, C., additional, Garcia-Vega, D., additional, Mont-Girbau, L., additional, Pardo, A., additional, Izurieta, C., additional, Boretti, I., additional, Hinojar, R., additional, Gonzalez-Gomez, A., additional, Casas, E., additional, Salido, L., additional, Barrios, V., additional, Ruiz, S., additional, Moya, JL., additional, Hernandez Antolin, R., additional, Jimenez Nacher, JL., additional, Chang, HJ., additional, Choi, HH., additional, Lee, SY., additional, Shim, CY., additional, Ha, JW., additional, Chung, N., additional, Ring, M., additional, Caidahl, K., additional, Eriksson, MJ., additional, Esposito, R., additional, Santoro, C., additional, Monteagudo, JM., additional, Trimarco, B., additional, Galderisi, M., additional, Baig, S., additional, Hayer, M., additional, Steeds, R., additional, Edwards, N., additional, Fusini, L., additional, Zagni, P., additional, Muratori, M., additional, Agostoni, P., additional, Gripari, P., additional, Ghulam Ali, S., additional, Fiorentini, C., additional, Valuckiene, Z., additional, Jurkevicius, R., additional, Peritore, A., additional, Botta, L., additional, Belli, O., additional, Musca, F., additional, Casadei, F., additional, Russo, C., additional, Giannattasio, C., additional, and Moreo, A., additional
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- 2016
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3. P650Influence of fetunin-a level on progression of calcific aortic valve stenosis The COFRASA - GENERAC StudyP651Common carotid artery remodeling 1 year after aortic valve surgeryP652Low gradient aortic stenosis with preserved ejection fraction: reclassification of severity by 3D transesophageal echocardiography. P653Results of balloon aortic valvuloplasty in patients with impaired left ventricle ejection fraction.P654Burden of associated aortic regurgitation in patients with mitral regurgitationP655Differences in right ventricular mechanics in acute and chronic ischemic mitral regurgitation after inferoposterior myocardial infarctionP656Tricuspid regurgitation in patients operated for severe symptomatic native aortic stenosis: pre-operative determinantsP657Echocardiographic diagnosis in patients with prosthetic or annuloplasty ring dysfunction: correlation with surgical findingsP659Agreement analisys of different three-dimensional transoesophageal echocardiographic modalities and cardiac CT scan in aortic annulus sizing for transapical heart valve implantationP660Elevated gradients after TAVR are associated with increased rehospitalization, but have no impact on mortality and major adverse cardiac eventsP661Echocardiographic characteristics of post-TAVI thrombosis and endocarditis: single-centre experienceP662Impact of mixed aortic valve disease in long-term mortality after transcatheter aortic valve implantationP663Quantification of mitral regurgitation during interventional valve repair: correlation between haemodynamic parameters and 3D color Doppler echocardiographyP664Mitraclip in functional mitral regurgitation: are immediate results the same in ischemic and non ischemic etiology?P665Left ventricular contractile reserve by stress echocardiography as a predictor of response to cardiac resynchronization therapy in heart failure: a meta-analysisP666Regardless of the definition used, left ventricular reverse remodeling is not different in fibrosis positive and negative dilated cardiomyopathy patientsP667Heterogeneity of LV contractile function by multidimensional strain in patients with EF<35%: Insights for the hemodynamic burdenP668Ability of 99mTc-DPD scintigraphy to predict conduction disorders requiring permanent pacemaker in patients with transthyretin-related cardiac amyloidosisP669Provocation of left ventricular outflow tract obstruction using nitrate inhalation in hypertrophic cardiomyopathy: relation to electromechanical delayP670Could echocardiographic features differentiate Fabry cardiomyopathy from sarcomeric forms of hypertrophic cardiomyopathy?P671Pregnancy is well tolerated in women with arrhythmogenic right ventricular cardiomyopathy P672Glycogen storage cardiomyopathy (PRKAG2): do particular echocardiography findings in established and advanced techniques are helpful in suggesting the diagnosis?P673Improvement of arterial stiffness and myocardial deformation in patients with poorly controlled diabetes mellitus type 2 after optimization of antidiabetic medication
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Kubota, N., primary, Petrini, J., primary, Gonzalez Gomez, A., primary, Sorysz, DS., primary, Monteagudo Ruiz, JM., primary, Tamulenaite, E., primary, Dumont, C., primary, De Chiara, B., primary, Polizzi, V., primary, Ali, M., primary, Spartera, M., primary, Stathogiannis, K., primary, Goebel, B., primary, Mesa Rubio, MD., primary, Ciampi, Q., primary, Wisniowska-Smialek, S., primary, Sade, LE., primary, Brun, S., primary, Hamed, W., primary, Militaru, S., primary, Castrini, AI., primary, Costa Santos, W., primary, Ikonomidis, I., primary, David Messika-Zeitoun, DMZ, additional, Ring, M., additional, Caidahl, K., additional, Eriksson, MJ., additional, Monteagudo, JM., additional, Fernandez-Golfin, C., additional, Izurieta, C., additional, Hinojar, R., additional, Garcia, A., additional, Casas, E., additional, Marco, A., additional, Jimenez-Nacher, JJ., additional, Zamorano, JL., additional, Daniec, M., additional, Stapor, M., additional, Tomala, M., additional, Nawrotek, B., additional, Rzeszutko, L., additional, Kleczynski, P., additional, Dziewierz, A., additional, Bagienski, M., additional, Zmudka, K., additional, Dudek, D., additional, Mesa, D., additional, Gonzalez-Alujas, T., additional, Sitges, M., additional, Carrasco-Chinchilla, F., additional, Li, CH., additional, Grande-Trillo, A., additional, Martinez, A., additional, Matabuena, J., additional, Alonso-Rodriguez, D., additional, Aquila, I., additional, Gonzalez-Gomez, A., additional, Valuckiene, Z., additional, Jurkevicius, R., additional, Galli, E., additional, Oger, E., additional, Hubert, A., additional, Leclercq, C., additional, Donal, E., additional, Quattrocchi, S., additional, Botta, L., additional, Casadei, F., additional, Peritore, A., additional, Belli, O., additional, Musca, F., additional, Russo, C., additional, Giannattasio, C., additional, Moreo, A., additional, Lo Presti, ML., additional, Pino, PG., additional, Madeo, A., additional, Bellavia, D., additional, Buffa, V., additional, Fiorilli, R., additional, Luzi, G., additional, Musumeci, F., additional, Nkomo, VT., additional, Pellikka, PA., additional, Connolly, HM., additional, Scott, CG., additional, Sandhu, GS., additional, Holmes, DR., additional, Rihal, CS., additional, Greason, KL., additional, Pislaru, SV., additional, Barletta, M., additional, Ancona, F., additional, Rosa, I., additional, Stella, S., additional, Marini, C., additional, Montorfano, M., additional, Latib, A., additional, Alfieri, O., additional, Margonato, A., additional, Colombo, A., additional, Agricola, E., additional, Toutouzas, K., additional, Drakopoulou, M., additional, Michelongona, A., additional, Latsios, G., additional, Synetos, A., additional, Kaitozis, O., additional, Mitropoulou, F., additional, Brili, S., additional, Tousoulis, D., additional, Rohm, I., additional, Hamadanchi, A., additional, Otto, S., additional, Jung, C., additional, Figulla, HR., additional, Schulze, PC., additional, Poerner, TC., additional, Gutierrez Ballesteros, G., additional, Aristizabal Duque, C., additional, Ruiz Ortiz, M., additional, Delgado Ortega, M., additional, Fernandez Cabeza, J., additional, Pan Alvarez-Osorio, M., additional, Lopez Granados, A., additional, Romero Moreno, M., additional, Suarez De Lezo Cruz-Conde, J., additional, Carpegiani, C., additional, Michelassi, C., additional, Villari, B., additional, Picano, E., additional, Rubis, P., additional, Biernacka-Fijalkowska, B., additional, Dziewiecka, E., additional, Khachatryan, L., additional, Faltyn, P., additional, Lesniak-Sobelga, A., additional, Hlawaty, M., additional, Kostkiewicz, M., additional, Podolec, P., additional, Bal, U., additional, Oguz, D., additional, Eroglu, S., additional, Pirat, B., additional, Muderrisoglu, H., additional, Pradel, S., additional, Mondoly, P., additional, Victor, G., additional, Pascal, P., additional, Galinier, M., additional, Carrie, D., additional, Maury, P., additional, Berry, I., additional, Lairez, O., additional, Badran, HMB, additional, Yaseen, RIY, additional, Yacoub, MAGDY, additional, Adam, RD., additional, Mursa, A., additional, Chivulescu, M., additional, Rosca, M., additional, Mandes, L., additional, Rusu, E., additional, Dima, L., additional, Fruntelata, A., additional, Popescu, BA., additional, Ginghina, CD., additional, Jurcut, RO., additional, Leren, IS., additional, Estensen, ME., additional, Klaeboe, LG., additional, Edvardsen, T., additional, Haugaa, KH., additional, Pena, JLB, additional, Sampaio, IH., additional, Siqueira, MHA, additional, Alves, MC., additional, Sternick, EB., additional, Pavlidis, G., additional, Lambadiari, V., additional, Kousathana, F., additional, Triantafyllidi, H., additional, Varoudi, M., additional, Vlastos, D., additional, Vlachos, S., additional, Dimitriadis, G., additional, and Lekakis, J., additional
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- 2016
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4. Degradation of antipyrine in water with activated persulfate aided with biochar of olive pomace.
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Durán A, Monteagudo JM, and Delgado J
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- Adsorption, Kinetics, Water chemistry, Water Purification methods, Charcoal chemistry, Olea, Water Pollutants, Chemical chemistry, Antipyrine chemistry
- Abstract
The degradation of antipyrine (AP) in water has been studied using persulfate activated with biochar obtained from gasification of olive pomace (BC) combined with ferric salts in the presence of UV-A radiation. Firstly, the adsorption of AP on biochar was evaluated. The data were adjusted using various kinetic models verifying that AP adsorption on BC occurs in three stages and follows pseudo-second order kinetics. Degradation tests show that the presence of iron or persulfate (PS) in binary systems with BC produces increases AP degradation when no radiation is used, reaching 75.7 % due to the ability of BC to donate electrons. On the other hand, addition of PS showed an increase in efficiency in the presence of BC (up to 79%). For ternary systems the best result was found when UVA/PS/Fe was used (100% of AP degradation in 30 min). The addition of UV-A radiation to the BC/PS system improves the degradation of the contaminant by only 6.7%, while the presence of iron in the studied conditions does not cause any improvement. A Central Composite Factorial Design of experiments was used to optimize the UVA/BC/PS/Fe system, leading to an 89.3% AP degradation rate in 90 min (k = 0.0134 min-1) under optimal conditions ([Fe(III)] = 10 mg/L, [PS] = 379 mg/L, [BC] = 500 mg/L). Although the best results were obtained for the UVA/PS/Fe process without BC, systems based on BC/PS can be considered as an alternative in cloudy days or when simple processes are selected due to economical/technical reasons., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2024
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5. Pupil reflex as a marker of activity and prognosis in heart failure: a longitudinal and prospective study.
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Zamorano M, Monteagudo JM, González E, Rayo I, Fernández S, Castillo M, Zhou Q, de la Villa P, and Zamorano JL
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- Humans, Male, Female, Prognosis, Prospective Studies, Aged, Middle Aged, Follow-Up Studies, Pupil physiology, Reflex, Pupillary physiology, Heart Failure physiopathology, Heart Failure diagnosis, Heart Failure mortality
- Abstract
Aims: Compensatory mechanisms in heart failure (HF) are triggered to maintain adequate cardiac output. Among them, hyperactivation of the sympathetic nervous system (SNS) is one of the main ones and carries a worse prognosis. The pupillary reflex depends on the SNS, and we can evaluate it through pupillometry. The aim of the study was to compare the differences in pupillary reflex between patients with acute HF and controls and to analyse whether these differences in pupillary reflex may offer a new and easy prognostic factor in such patients., Methods and Results: We prospectively and consecutively included 107 patients admitted with decompensated HF. Quantitative pupillometry was performed with the NeuroOptics pupillometry during the first 24 h after admission and prior to discharge. The results were compared with those of a group of 100 healthy volunteers who also underwent pupillometry. The maximum baseline pupil size (MBPS) and the minimum pupil diameter (MPD) were measured. Patients with decompensated HF have a higher MBPS (3.64 ± 0.81) and higher MPD (2.60 ± 0.58) than HF patients at discharge and in the control group (P-value = 0.01 and 0.01, respectively). Also, HF patients presented an improvement in pupillometric values at discharge [MBPS (3.47 ± 0.79) and MPD (2.51 ± 0.58)] and showed no differences compared with the control group [MBPS (3.34 ± 0.82) and MPD (2.40 ± 0.53)] (P-value = 0.19 and 0.14, respectively). In addition, MBPS provides a good independent predictor of in-hospital and 1 month mortality in patients admitted with HF. Six patients (5.61%) died during hospital admission, and 11 patients (10.2%) died in the first month after discharge. Also, four patients (3.74%) were readmitted within 1 month of discharge. The receiver operating characteristic (ROC) curve for predicting in-hospital mortality through MBPS was 0.823. No patient with an MBPS < 3.7 mm died. The ROC curve for predicting combined mortality or readmission within the first month for MBPS was 0.698., Conclusions: Pupillometry may be a new, non-invasive, and simple tool to determine the status of SNS, help in the prognostic stratification of acute HF patients, and improve therapeutic management., (© 2024 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)
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- 2024
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6. STREI: a new index of right heart function in isolated severe tricuspid regurgitation by speckle-tracking echocardiography.
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Hinojar R, Fernández-Golfín C, González Gómez A, García-Martin A, Monteagudo JM, García Lunar I, García Sebastian C, Pardo A, Sanchez Recalde A, and Zamorano JL
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- Humans, Echocardiography methods, Prognosis, Heart Ventricles diagnostic imaging, Ventricular Function, Right, Tricuspid Valve Insufficiency, Heart Failure, Ventricular Dysfunction, Right
- Abstract
Aims: Right ventricular (RV) performance determines clinical management in severe tricuspid regurgitation (TR). Right atrial (RA) function complements RV assessment in TR. This study aimed to design a novel index by speckle-tracking echocardiography (STREI index) integrating RA and RV strain information and to evaluate the clinical utility of combining RV and RA strain for prediction of cardiovascular (CV) outcomes., Methods and Results: Consecutive patients with at least (≥) severe TR evaluated in the Heart Valve Clinic (n = 300) were prospectively included. An additional independent TR cohort was included for external validation (n = 50). STREI index was developed with the formula: [2 ∗ RV-free wall longitudinal strain (RV-FWLS)] + reservoir RA strain (RASr). The composite endpoint included hospital admission due to heart failure and all-cause mortality. A total of 176 patients with ≥severe TR were finally included. STREI index identified a higher percentage of patients with RV dysfunction compared with conventional parameters. After a median follow-up of 2.2 years (interquartile range: 12-41 months), a total of 38% reached the composite endpoint. STREI values were predictors of outcomes independently of TR severity and RV dimensions. The combination of prognostic cut-off values of RASr (<10%) and RV-FWLS (>-20%) (STREI stratification) stratified four different groups of risk independently of TR severity, RV dimensions, and clinical status (adj HR per stratum 1.89 (1.4-2.34), P < 0.001). Pre-defined cut-off values achieved similar prognostic performance in the validation cohort (n = 50)., Conclusion: STREI index is a novel parameter of RV performance that independently predicts CV events. The combination of RA and RV strain stratifies better patients' risk, reflecting a broader effect of TR on right heart chambers., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2024
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7. The 4A classification for patients with tricuspid regurgitation.
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González-Gómez A, Fernández-Golfín C, Hinojar R, Monteagudo JM, García A, García-Sebastián C, García-Lunar I, Sánchez-Recalde Á, Salido L, Pardo A, and Zamorano JL
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- Female, Humans, Aged, Aged, 80 and over, Male, Prognosis, Morbidity, Incidence, Treatment Outcome, Tricuspid Valve Insufficiency diagnosis, Tricuspid Valve Insufficiency epidemiology, Heart Failure diagnosis, Heart Failure complications
- Abstract
Introduction and Objectives: Significant tricuspid regurgitation (TR) is associated with increased morbidity and mortality. Clinical evaluation of TR patients is challenging. Our aim was to establish a new clinical classification specific for patients with TR, the 4A classification, and evaluate its prognostic performance., Methods: We included patients with isolated TR that was at least severe and without previous episodes of heart failure (HF) who were assessed in the heart valve clinic. We registered signs and symptoms of asthenia, ankle swelling, abdominal pain or distention and/or anorexia and followed up the patients every 6 months. The 4A classification ranged from A0 (no A) to A3 (3 or 4 As present). We defined a combined endpoint consisting of hospital admission due to right HF or cardiovascular mortality., Results: We included 135 patients with significant TR between 2016 and 2021 (69% females, mean age 78±7 years). During a median follow-up of 26 [IQR, 10-41] months, 39% (n=53) patients had the combined endpoint: 34% (n=46) were admitted for HF and 5% (n=7) died. At baseline, 94% of the patients were in NYHA I or II, while 24% were in classes A2 or A3. The presence of A2 or A3 conferred a high incidence of events. The change in 4A class remained an independent marker of HF and cardiovascular mortality (adjusted HR per unit of change of 4A class, 1.95 [1.37-2.77]; P<.001)., Conclusions: This study reports a novel clinical classification specifically for patients with TR that is based on signs and symptoms of right HF and has prognostic value for events., (Copyright © 2023. Published by Elsevier España, S.L.U.)
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- 2023
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8. Insights into the adsorption of CO 2 generated from synthetic urban wastewater treatment on olive pomace biochar.
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Monteagudo JM, Durán A, Mänttäri M, and López S
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- Wastewater, Carbon Dioxide, Adsorption, Hydrogen Peroxide, Charcoal chemistry, Olea, Water Purification methods
- Abstract
In this investigation, a sustainable and low-cost method to capture CO
2 generated from the treatment of urban wastewater was evaluated. We studied the adsorption of CO2 on olive pomace biochar. The experiments of degradation of synthetic wastewater mimicking effluents of municipal wastewater treatment plant (WWTP) with an initial Total Organic Carbon (TOC) concentration of 10 mg L-1 were conducted by using the UV-C/H2 O2 process in the absence or presence of biochar. The biochar was placed in a fixed bed column through which air from the UV reactor was circulated. First, the effects of different parameters such as H2 O2 initial concentration and pH on wastewater mineralization efficiency were determined. Total Organic Carbon (TOC) removal was 87% in 2 h under optimal degradation conditions. The maximal concentration of CO2(gas) in air, in a closed system (air volume: 7.3 10-4 m3 ), after 11 h was 12,500 μmol mol-1 in the absence of biochar and only 150 μmol mol-1 when 10 g biochar were used. The results proved that by combining biochar with oxidative degradation of organic compounds, it is possible to mineralize organic compounds and reduce the requisite CO2 emissions by about 99%. The experimental equilibrium results were fit well with both Langmuir and Freundlich isotherms models concluding that CO2 adsorption on biochar followed both chemisorption and physisorption and both monolayer and multi-layer CO2 adsorption could occur. The total desorption of CO2 from biochar was reached in 120 min by simultaneously increasing the temperature to 150 °C and introducing a purge N2(gas) ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2023
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9. Clinical utility and prognostic value of right atrial function in severe tricuspid regurgitation: one more piece of the puzzle.
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Hinojar R, Fernández-Golfín C, González Gómez A, García-Martin A, Monteagudo JM, García Lunar I, García Sebastian C, Rivas S, Sanchez Recalde A, and Zamorano JL
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- Humans, Prognosis, Atrial Function, Right, Echocardiography, Retrospective Studies, Tricuspid Valve Insufficiency diagnostic imaging, Atrial Fibrillation diagnostic imaging, Heart Failure
- Abstract
Aims: The optimal management of severe tricuspid regurgitation (TR) remains controversial. While right ventricular systolic function is an established prognostic marker of outcomes, the potential role of right atrial (RA) function is unknown. This study aimed to describe RA function by 2D speckle-tracking echocardiography (STE) in at least severe TR and to evaluate its potential association with cardiovascular outcomes., Methods and Results: Consecutive patients with at least (≥) severe TR (severe, massive, or torrential TR) evaluated in the Heart Valve Clinic following a comprehensive clinical protocol were included. Consecutive control subjects and patients with permanent isolated atrial fibrillation (AF) were included for comparison (control and AF group, respectively). RA function was measured with 2D-STE and two components of RA function were calculated: reservoir (RASr) and contractile (RASct) strain (AutoStrain, Philips Medical Systems the EPIQ system). A combined endpoint of hospital admission due to heart failure (HF) or all-cause mortality was defined. Patients with ≥ severe TR (n = 140) showed lower RASr compared with controls (n = 20) and with the AF group (n = 20) (P < 0.001). Atrial TR showed lower RASr compared with other aetiologies of TR (P < 0.001). After a median follow-up of 2.2 years (IQR: 12-41 months), RASr remained an independent predictor of mortality and HF. A cut-off value of RASr of <9.4% held the best accuracy to predict outcomes., Conclusion: RA function by 2D-STE independently predicts mortality and HF hospitalizations in patients with ≥ severe TR., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2023
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10. Prognostic Impact of Right Ventricular Strain in Isolated Severe Tricuspid Regurgitation.
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Hinojar R, Zamorano JL, González Gómez A, García-Martin A, Monteagudo JM, García Lunar I, Sanchez Recalde A, and Fernández-Golfín C
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- Humans, Prognosis, Echocardiography adverse effects, Heart Ventricles diagnostic imaging, Ventricular Function, Right, Tricuspid Valve Insufficiency diagnostic imaging, Heart Failure, Ventricular Dysfunction, Right diagnostic imaging, Ventricular Dysfunction, Right etiology
- Abstract
Background: Right ventricular (RV) systolic function is an established marker of outcomes in patients with severe tricuspid regurgitation (TR). Timely detection of RV dysfunction using conventional two-dimensional echocardiography is challenging. RV strain has emerged as an accurate and sensitive tool for the evaluation of RV function, with the capability to detect subclinical RV dysfunction. The aim of this study was to evaluate the prognostic value of RV strain parameters in early stages of severe TR., Methods: Consecutive patients with at least severe TR (severe, massive, or torrential) and the absence of a formal indication for tricuspid valve intervention in secondary TR evaluated in the Heart Valve Clinic were prospectively included. RV systolic function was measured using conventional echocardiographic indices (RV fractional area change, tricuspid annular plane systolic excursion, and Doppler tissue imaging S wave [S']) and speckle-tracking echocardiography-derived automatic peak global longitudinal strain and free wall longitudinal strain (FWLS) using an automated two-dimensional strain analytic software. A combined end point of hospital admission due to heart failure or all-cause mortality was defined., Results: A total of 266 patients were enrolled in the study, and 151 were ultimately included. Strain parameters detected a higher percentage of abnormal RV values compared with conventional indices. During a median follow-up period of 26 months (interquartile range, 13-42 months), 35% of the patients reached the combined end point. Cumulative event-free survival was significantly worse in patients with impaired RV global longitudinal strain and RV FWLS. Conventional indices of RV systolic function were not associated with outcomes (P > .05 for all). On multivariate analysis, RV FWLS was independently associated with mortality and heart failure (adjusted hazard ratio for abnormal RV FWLS, 5.90; 95% CI, 3.17-10.99; P < .001)., Conclusion: In early stages of severe TR, RV FWLS is more frequently impaired compared with conventional indices of RV function. Among all parameters, RV FWLS is the strongest predictor of mortality and heart failure, independent of additional prognostic markers., (Copyright © 2023 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)
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- 2023
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11. Capture of ambient air CO 2 from municipal wastewater mineralization by using an ion-exchange membrane.
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Monteagudo JM, Durán A, Valderas V, Chen X, and Shi X
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- Adsorption, Hydrogen Peroxide, Ion Exchange, Carbon Dioxide, Wastewater
- Abstract
The capture of ambient air CO
2(gas) from synthetic urban wastewater mineralization reaction was studied. An ion exchange membrane was used as sorbent, which adsorbs CO2 when dry and releases it when wet. The UV/H2 O2 degradation process was chosen to convert Total Organic Carbon (TOC) to carbon dioxide due to its advantages of convenience and fast kinetics over the conventional biological treatment that is usually used in urban wastewater treatment plants. In the first phase, experiments combining UV-C light and H2 O2 were carried out to select the optimal values of the following parameters: pH, the dose of H2 O2 and temperature. In the second stage, the CO2(gas) emission into the air from the degradation of organic compounds present in wastewater during UV/H2 O2 process in the absence or presence of ion exchange membranes was evaluated. The effects of parameters such as temperature or air humidity were studied. A qualitative study of desorption was carried out to check the viability of reuse CO2 captured in the membrane. Finally, a similar CO2(gas) adsorption capacity after five cycles of adsorption and regeneration of the membranes was observed, being percentage loss of around 4%., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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12. Impact of right ventricular systolic function in patients with significant tricuspid regurgitation. A cardiac magnetic resonance study.
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Hinojar R, Gómez AG, García-Martin A, Monteagudo JM, Fernández-Méndez MA, de Vicente AG, Salinas GLA, Zamorano JL, and Fernández-Golfín C
- Subjects
- Aged, Aged, 80 and over, Female, Humans, Magnetic Resonance Spectroscopy, Stroke Volume, Systole, Ventricular Function, Right, Tricuspid Valve Insufficiency diagnostic imaging, Tricuspid Valve Insufficiency epidemiology, Ventricular Dysfunction, Right diagnostic imaging
- Abstract
Background: Right ventricle (RV) dilatation and dysfunction are established criteria for intervention in severe tricuspid regurgitation (TR); however thresholds to support intervention are lacking. New measures of RV function such as RV shortening (RVS) and effective RV ejection fraction (eRVEF) may be earlier markers of RV dysfunction., Purpose: to compare the prognostic impact of different parameters of RV function and to describe cut-off values of RV size/function and TR severity of poor prognosis., Methods: Consecutive patients evaluated in the Heart Valve Clinic with significant TR (severe, massive or torrential TR) undergoing a CMR study were included. In addition to parameters of biventricular volume and function, RVS and eRVEF were assessed. A combined endpoint of hospital admission due to right heart failure and cardiovascular mortality was defined., Results: 75 patients were included (age 75 ± 8 years, female 75%). During a median follow-up of 3 years (IQR: 1.4-3.9 years), 39% experienced the endpoint. Cut-off values of worse prognosis were: RVS ≥ -14%, eRVEF ≤34%, RVEF ≤58%, RV-EDV ≥100 ml/m2, TR regurgitant fraction (TRF) ≥40% and TR volume ≥ 42 ml. RVS and eRVEF identified higher rates of RV dysfunction than RVEF. After adjustment for age and LVEF, both eRVEF ≤34% (HR: 5.29 [2.25-12.4]) and RVS ≥ -14% (HR: 3.46 [1.13-9.17]) were significantly associated with outcomes. Among all parameters of RV function, eRVEF was the strongest predictor of outcomes, incremental to RVEF (ΔC-statistic 0.139 [0.040-0.237], p = 0.005). Patients with eRVEF ≤34% and RV-EDV ≥100 ml/m2 or eRVEF ≤34% and TRF ≥40% had the worst prognosis (p < 0.01 for both)., Conclusion: RVS and eRVEF identify higher rates of RV dysfunction beyond RVEF. Among all measures, eRVEF held the strongest association with outcomes, incremental to RVEF., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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13. Preoperative clinical model to predict myocardial injury after non-cardiac surgery: a retrospective analysis from the MANAGE cohort in a Spanish hospital.
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Serrano AB, Gomez-Rojo M, Ureta E, Nuñez M, Fernández Félix B, Velasco E, Burgos J, Popova E, Urrutia G, Gomez V, Del Rey JM, Sanjuanbenito A, Zamora J, Monteagudo JM, Pestaña D, de la Torre B, and Candela-Toha Á
- Subjects
- Cohort Studies, Humans, Retrospective Studies, Risk Factors, Hospitals, Nomograms
- Abstract
Objectives: To determine preoperative factors associated to myocardial injury after non-cardiac surgery (MINS) and to develop a prediction model of MINS., Design: Retrospective analysis., Setting: Tertiary hospital in Spain., Participants: Patients aged ≥45 years undergoing major non-cardiac surgery and with at least two measures of troponin levels within the first 3 days of the postoperative period. All patients were screened for the MANAGE trial., Primary and Secondary Outcome Measures: We used multivariable logistic regression analysis to study risk factors associated with MINS and created a score predicting the preoperative risk for MINS and a nomogram to facilitate bed-side use. We used Least Absolute Shrinkage and Selection Operator method to choose the factors included in the predictive model with MINS as dependent variable. The predictive ability of the model was evaluated. Discrimination was assessed with the area under the receiver operating characteristic curve (AUC) and calibration was visually assessed using calibration plots representing deciles of predicted probability of MINS against the observed rate in each risk group and the calibration-in-the-large (CITL) and the calibration slope. We created a nomogram to facilitate obtaining risk estimates for patients at pre-anaesthesia evaluation., Results: Our cohort included 3633 patients recruited from 9 September 2014 to 17 July 2017. The incidence of MINS was 9%. Preoperative risk factors that increased the risk of MINS were age, American Status Anaesthesiology classification and vascular surgery. The predictive model showed good performance in terms of discrimination (AUC=0.720; 95% CI: 0.69 to 0.75) and calibration slope=1.043 (95% CI: 0.90 to 1.18) and CITL=0.00 (95% CI: -0.12 to 0.12)., Conclusions: Our predictive model based on routinely preoperative information is highly affordable and might be a useful tool to identify moderate-high risk patients before surgery. However, external validation is needed before implementation., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2021
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14. Prognostic implications of cardiac magnetic resonance feature tracking derived multidirectional strain in patients with chronic aortic regurgitation.
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Fernández-Golfín C, Hinojar-Baydes R, González-Gómez A, Monteagudo JM, Esteban A, Alonso-Salinas G, Fernández MA, García-Martín A, Santoro C, Pascual-Izco M, Jiménez-Nacher JJ, and Zamorano JL
- Subjects
- Echocardiography, Humans, Magnetic Resonance Imaging, Cine, Magnetic Resonance Spectroscopy, Predictive Value of Tests, Prognosis, Ventricular Function, Left, Aortic Valve Insufficiency diagnostic imaging, Ventricular Dysfunction, Left diagnostic imaging
- Abstract
Objective: Speckle-tracking echocardiography (STE) deformation parameters detect latent LV dysfunction in chronic aortic regurgitation (AR) and are associated with outcomes. The aim of the study was to evaluate cardiac magnetic resonance (CMR) feature tracking (FT) deformation parameters in asymptomatic patients with AR and implications in outcomes., Methods: Fifty-five patients with AR and 54 controls were included. Conventional functional CMR parameters, aortic regurgitant volume, and fraction were assessed. CMR-FT analysis was performed with a dedicated software. Clinical data was obtained from hospital records. A combined endpoint included all-cause mortality, cardiovascular mortality, aortic valve surgery, or cardiovascular hospital admission due to heart failure., Results: Left ventricular (LV) mechanics is impaired in patients with significant AR. Significant differences were noted in global longitudinal strain (GLS) between controls and AR patients (- 19.1 ± 2.9% vs - 16.5 ± 3.2%, p < 0.001) and among AR severity groups (- 18.3 ± 3.1% vs - 16.2 ± 1.6% vs - 15 ± 3.5%; p = 0.02 for AR grades I-II, III, and IV). In univariate and multivariate analyses, circumferential strain (GCS) and global radial strain (GRS) but not GLS were associated with and increased risk of the end point with a HR of 1.26 (p = 0.016, 1.04-1.52) per 1% worsening for GCS and 0.90 (p = 0.012, 0.83-0.98) per 1% worsening for GRS., Conclusions: CMR-FT myocardial deformation parameters are impaired in patients with AR not meeting surgical criteria. GLS decreases early in the course of the disease and is a marker of AR severity while GCS and GRS worsen later but predict a bad prognosis, mainly the need of aortic valve surgery., Key Points: • CMR feature tracking LV mechanic parameters may be reduced in significant chronic AR with normal EF. • LV mechanics, mainly global longitudinal strain, worsens as AR severity increases. • LV mechanics, specially global radial and circumferential strain, is associated with a worse prognosis in AR patients.
- Published
- 2021
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15. Quantitative cardiovascular magnetic resonance myocardial perfusion mapping to assess hyperaemic response to adenosine stress.
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Kotecha T, Monteagudo JM, Martinez-Naharro A, Chacko L, Brown J, Knight D, Knott KD, Hawkins P, Moon JC, Plein S, Xue H, Kellman P, Lockie T, Patel N, Rakhit R, and Fontana M
- Subjects
- Adenosine pharmacology, Coronary Circulation, Humans, Magnetic Resonance Imaging, Cine, Magnetic Resonance Spectroscopy, Myocardium, Perfusion, Predictive Value of Tests, Vasodilator Agents, Coronary Artery Disease, Hyperemia, Myocardial Perfusion Imaging
- Abstract
Aims: Assessment of hyperaemia during adenosine stress cardiovascular magnetic resonance (CMR) remains a clinical challenge with lack of a gold-standard non-invasive clinical marker to confirm hyperaemic response. This study aimed to validate maximum stress myocardial blood flow (SMBF) measured using quantitative perfusion mapping for assessment of hyperaemic response and compare this to current clinical markers of adenosine stress., Methods and Results: Two hundred and eighteen subjects underwent adenosine stress CMR. A derivation cohort (22 volunteers) was used to identify a SMBF threshold value for hyperaemia. This was tested in a validation cohort (37 patients with suspected coronary artery disease) who underwent invasive coronary physiology assessment on the same day as CMR. A clinical cohort (159 patients) was used to compare SMBF to other physiological markers of hyperaemia [splenic switch-off (SSO), heart rate response (HRR), and blood pressure (BP) fall]. A minimum SMBF threshold of 1.43 mL/g/min was derived from volunteer scans. All patients in the coronary physiology cohort demonstrated regional maximum SMBF (SMBFmax) >1.43 mL/g/min and invasive evidence of hyperaemia. Of the clinical cohort, 93% had hyperaemia defined by perfusion mapping compared to 71% using SSO and 81% using HRR. There was no difference in SMBFmax in those with or without SSO (2.58 ± 0.89 vs. 2.54 ± 1.04 mL/g/min, P = 0.84) but those with HRR had significantly higher SMBFmax (2.66 1.86 mL/g/min, P < 0.001). HRR >15 bpm was superior to SSO in predicting adequate increase in SMBF (AUC 0.87 vs. 0.62, P < 0.001)., Conclusion: Adenosine-induced increase in myocardial blood flow is accurate for confirmation of hyperaemia during stress CMR studies and is superior to traditional, clinically used markers of adequate stress such as SSO and BP response., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
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16. New insights of tricuspid regurgitation: a large-scale prospective cohort study.
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Vieitez JM, Monteagudo JM, Mahia P, Perez L, Lopez T, Marco I, Perone F, González T, Sitges M, Bouzas A, González-Salvado V, Li CH, Alonso D, Carrasco F, Adeba A, de la Hera JM, Fernandez-Golfin C, and Zamorano JL
- Subjects
- Cohort Studies, Humans, Prospective Studies, Retrospective Studies, Severity of Illness Index, Stroke Volume, Treatment Outcome, Ventricular Function, Left, Heart Valve Prosthesis Implantation, Tricuspid Valve Insufficiency diagnostic imaging, Tricuspid Valve Insufficiency epidemiology, Tricuspid Valve Insufficiency surgery
- Abstract
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., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
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17. Right ventricle assessment in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation.
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Pardo Sanz A, Santoro C, Hinojar R, Salido L, Rajjoub EA, Monteagudo JM, García A, González A, Hernández-Antolín R, Sánchez Recalde Á, Zamorano JL, and Fernández-Golfín C
- Subjects
- Aged, Aged, 80 and over, Female, Heart Ventricles diagnostic imaging, Humans, Male, Ventricular Function, Right, Aortic Valve Stenosis complications, Aortic Valve Stenosis diagnostic imaging, Aortic Valve Stenosis surgery, Transcatheter Aortic Valve Replacement, Ventricular Dysfunction, Right surgery
- Abstract
Introduction: Limited data are available regarding the evaluation of right ventricular (RV) performance in patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI)., Objective: To evaluate the prevalence of RV dysfunction in patients with severe AS undergoing TAVI and long-term changes., Methods: Consecutive patients with severe AS undergoing TAVI from January 2016 to July 2017 were included. RV anatomical and functional parameters were analyzed: RV diameters, fractional area change, tricuspid annular plane systolic excursion (TAPSE), S-wave tissue Doppler of the tricuspid annulus (RV-S'TDI), global longitudinal strain (RV-GLS), and free wall strain (RV-FWS). Preprocedure and 1-year echo were analyzed., Results: Final population included 114 patients, mean age 83.63 ± 6.31 years, and 38.2% women. The prevalence of abnormal RV function was high, variable depending on the parameter that we analyzed, and it showed a significant reduction 1 year after TAVI implantation: 13.9% vs 6.8% (TAPSE < 17mm), P = .04; 26.3% vs 20% (fractional area change < 35%), P = .048; 41.2% vs 29.2% (RV-S'TDI < 9.5cm/s), P = .04; 48.7% vs 39.5% (RV-GLS > [20]), P = .049; and 48.7% vs 28.9% (RV-FWS > [20]), P = .03. Significant differences were noted between patients with low-flow (LF) vs normal-flow (NF) AS in RV dysfunction prevalence as well as in RV function recovery which is less evident in LF compared with NF patients., Conclusions: RV dysfunction is high among symptomatic AS patients undergoing TAVI, with variable prevalence depending on the echocardiographic parameter used., (© 2020 Wiley Periodicals, Inc.)
- Published
- 2020
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18. Solar photo-degradation of aniline with rGO/TiO 2 composites and persulfate.
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Durán A, Monteagudo JM, Martín IS, Merino S, Chen X, and Shi X
- Abstract
The solar photodegradation of aniline using reduced graphene oxide-based composites (rGO/TiO
2 ) and different electron acceptors such as H2 O2 and persulfate (PS) has been studied. To this end, an innovative self-sufficient drum reactor (operating with solar irradiation and artificial UV light) has been employed. The role of radicals and the new graphene morphology is evaluated. Finally, changes in the degradation/mineralization mechanism are explained according to intermediates evolution (obtained from mass spectroscopy). In the Solar/rGO/TiO2 /H2 O2 system, hydroxyl radicals react with the reduced graphene oxide (rGO) producing oxidized rGO (OrGO). The process creates new pores increasing surface area favouring adsorption. Also, other radicals such as superoxide or singlet oxygen are also formed, affecting the degradation mechanism. The hole reacts with adsorbed aniline to form the aniline-radical-cation. Nitrosobenzene is then formed with the active participation of superoxide radical anion, finally yielding azobenzene. It was found that the addition of 2.5% wt of rGO increases mineralization from 0 to 14% during the solar stage after 120 min, reaching 82.5% when lamps are switched on after 240 min. On the other hand, activation of PS with UV-C light is a very efficient process, since aniline is wholly degraded in 10-20 min depending on PS initial concentration, reaching a high mineralization degree close to 90% in 120 min. During this process, degradation occurs in a very different route, via the formation of phenol. In the first stage (t < 25 min), sulfate radical is the primary oxidant involved to yield benzoquinone. In a second step (t > 25 min), hydroxyl radicals play the leading role to reach C2 -C6 organic acids., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
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19. Global longitudinal strain is a hallmark of cardiac damage in mitral regurgitation: the Italian arm of the European Registry of mitral regurgitation (EuMiClip).
- Author
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Santoro C, Galderisi M, Esposito R, Buonauro A, Monteagudo JM, Sorrentino R, Lembo M, Fernandez-Golfin C, Trimarco B, and Zamorano JL
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Heart Ventricles physiopathology, Humans, Italy, Male, Middle Aged, Mitral Valve Insufficiency physiopathology, Registries, Retrospective Studies, Risk Factors, Ventricular Function, Left physiology, Young Adult, Echocardiography, Doppler methods, Heart Atria diagnostic imaging, Heart Ventricles diagnostic imaging, Mitral Valve diagnostic imaging, Mitral Valve Insufficiency diagnosis, Myocardial Contraction physiology, Stroke Volume physiology
- Abstract
Background: The search for reliable cardiac functional parameters is crucial in patients with mitral regurgitation (MR). In the Italian arm of the European Registry of MR, we compared the ability of global longitudinal strain (GLS) and left ventricular (LV) ejection fraction (LVEF) to detect cardiac damage in MR., Methods: Five hundred four consecutive patients with MR underwent a complete echo-Doppler exam. A total of 431, 53 and 20 patients had degenerative, secondary and mixed MR, respectively. The main echocardiographic parameters, including LV and left atrial (LA) size measurements, pulmonary artery systolic pressure (PASP) and GLS were compared between patients with mild MR (n = 392) vs. moderate to severe MR (n = 112)., Results: LVEF and GLS were related one another in the pooled population, and separately in patients with mild and moderate/severe MR (all p < 0.0001). However, a certain number of patients were above the upper or below the lower limits of the 95% confidence interval (CI) of the normal relation in the pooled population and in patients with mild MR. Only 2 patients were below the 95% CI in moderate to severe MR. After adjusting for confounders by separate multivariate models, LVEF and GLS were independently associated with LV and left atrial size in the pooled population and in mild and moderate/severe MR. GLS, but not LVEF, was also independently associated with PASP in patients with mild and moderate to severe MR., Conclusions: Both LVEF and GLS are independently associated with LV and LA size, but only GLS is related to pulmonary arterial pressure. GLS is a powerful hallmark of cardiac damage in MR.
- Published
- 2019
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20. Mid-term outcome of severe tricuspid regurgitation: are there any differences according to mechanism and severity?
- Author
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Santoro C, Marco Del Castillo A, González-Gómez A, Monteagudo JM, Hinojar R, Lorente A, Abellás M, Vieitez JM, Garcia Martìn A, Casas Rojo E, Ruíz S, Barrios V, Luis Moya J, Jimenez-Nacher JJ, Zamorano Gomez JL, and Fernández-Golfín C
- Subjects
- Aged, 80 and over, Female, Humans, Male, Prognosis, Retrospective Studies, Severity of Illness Index, Tricuspid Valve Insufficiency classification, Tricuspid Valve Insufficiency etiology, Echocardiography methods, Tricuspid Valve Insufficiency diagnostic imaging, Tricuspid Valve Insufficiency physiopathology
- Abstract
Aims: Patients with significant tricuspid regurgitation (TR) addressed according the new classification in torrential TR may have different prognosis compared with just severe TR patients. We sought to determine distribution and mechanism of consecutive severe TR patients, in accordance with aetiology and severity by applying the new proposed classification scheme and their long-term outcomes., Methods and Results: Between January and December 2013, 249 patients with significant TR referred to the cardiac imaging unit (mean age 79.9 ± 10.2 years; 29.8% female) were included. Patients were divided according to aetiology in six groups, and TR severity was reclassified into severe, massive, and torrential TR. The follow-up period was of 313 ± 103 days. When considering cardiovascular mortality, patients in the massive/torrential group showed the highest number of events (P < 0.007). Patients with TR due to pulmonary diseases had the worst prognosis according to different aetiology. Noteworthy, the best predictors for the combined endpoint [cardiovascular mortality and readmission admission for heart failure (HF)] were TR severity according to the new classification [hazard ratio (HR) 2.48, 95% confidence interval (CI) 1.25-4.93] and clinical scores such as New York Heart Association classification and congestive status (HR 1.78, 95% CI 1.28-2.49; HR 2.08, 95% CI 1.06-4.06, respectively)., Conclusion: Patients with massive/torrential TR and patients with comorbidities, especially pulmonary disease, were identified as populations at higher risk of death and readmission for HF. New classification scheme and clinical assessment may establish who may benefit the most of intensive therapeutic treatments and intervention on the tricuspid valve., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2019. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2019
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21. Energy Dissipation in Resynchronization Therapy: Impact of Atrioventricular Delay.
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Rodríguez Muñoz D, Moya Mur JL, Moreno J, Fernández-Golfín C, Franco E, Monteagudo JM, Matía R, Hernández-Madrid A, and Zamorano JL
- Subjects
- Aged, Blood Flow Velocity, Female, Heart, Heart Conduction System physiopathology, Heart Failure physiopathology, Humans, Male, Prospective Studies, Atrioventricular Node physiopathology, Cardiac Output, Cardiac Resynchronization Therapy, Echocardiography methods, Heart Failure diagnostic imaging, Heart Failure therapy
- Abstract
Background: Optimal atrioventricular delay (AVD) achieves maximum cardiac output in patients undergoing cardiac resynchronization therapy (CRT). Nonoptimal AVD decreases left ventricular (LV) end-diastolic volume and causes loss of flow momentum prior to LV ejection., Objective: We investigated the potential role of energy dissipation (ED) in these changes in cardiac output through the study of intraventricular flow. We hypothesized that short and long AVD increases ED when compared with optimal AVD by altering the physiologic flow mechanics that preserve kinetic energy in the LV., Methods: Forty-four patients under CRT underwent echocardiographic LV flow analysis under optimal, short, and long AVD. LV ED and vortical flow in the inflow-outflow tract were studied during the end-diastolic and early systolic period, and paired comparisons were obtained between optimal and nonoptimal values., Results: ED in the left ventricle was minimal in optimal AVD and significantly increased with nonoptimal values (79.1 ± 27.5 J/m·sec in optimal AVD vs 96.5 ± 34.7 J/m·sec in short AVD; n = 18, P = .006; 123.3 ± 67.6 J/m·sec in optimal AVD vs 292.4 ± 202.5 J/m·sec in long AVD; P < .001). Increase in ED occurred due to inadequate flow redirection toward the outflow tract in short AVD and due to both turbulence and prolonged ineffective flow rotation in long AVD., Conclusions: Optimal AVD in resynchronization therapy favors physiological vortex flow patterns in the left ventricle during the end-diastolic and early systolic period. These patterns are altered when nonoptimal values are programmed, increasing ED., (Copyright © 2019 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)
- Published
- 2019
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22. Operation costs of the solar photo-catalytic degradation of pharmaceuticals in water: A mini-review.
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Durán A, Monteagudo JM, and San Martín I
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- Wastewater analysis, Water Pollutants, Chemical chemistry, Wastewater economics, Water chemistry, Water Pollutants, Chemical economics
- Abstract
The removal of pharmaceuticals present in wastewater is receiving more and more attention since most of them are refractory to traditional biological treatments. Many advanced oxidation processes have been reported in literature. However, cost estimations are not available for most of them. Recently, more environment friendly processes using solar radiation are gaining importance. The solar photo-Fenton process has been used with different reactor configurations and scales and seems to be the most promising technology for reducing operation costs. In addition, the use of ferrioxalate-aided systems allows the use of pHs close to neutrality, that reduces costs before disposal (not calculated here). The possible use of photovoltaic panels for an energy-free process makes it very interesting for an economic evaluation. Results for the homogeneous solar photo-Fenton process show that when pure compounds are present in water, mineralization is in the range 18-21% with an estimated operation cost of 0.739-0.85 €/m
3 . An increase in mineralization up to 60-80.6% requires either the use of ferrioxalate (slightly increasing costs to 1.1-1.56 €/m3 ) or the addition of very high concentration of H2 O2 , that rises costs substantially. The presence of pharmaceuticals in a Waste Water Treatment Plant effluent reduces mineralization (maximum of 20%) also increasing costs. On the other hand, published results confirm that heterogeneous photocatalysis with TiO2 (both suspended or immobilized) is still far to compete with homogeneous photo-Fenton process in operation costs. The development of new reactor systems and modified photo-catalysts are needed to compete as an efficient applicable technology in the near future., (Copyright © 2018 Elsevier Ltd. All rights reserved.)- Published
- 2018
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23. Large-scale assessment of aortic stenosis: facing the next cardiac epidemic?
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Ramos J, Monteagudo JM, González-Alujas T, Fuentes ME, Sitges M, Peña ML, Carrasco-Chinchilla F, Echeverría T, Bouzas A, Forteza Alberti JF, Mesa D, De La Hera JM, and Zamorano JL
- Subjects
- Aged, Aged, 80 and over, Aortic Valve Insufficiency complications, Aortic Valve Stenosis etiology, Aortic Valve Stenosis physiopathology, Atrial Fibrillation complications, Echocardiography, Female, Humans, Male, Middle Aged, Mitral Valve Insufficiency complications, Prospective Studies, Ventricular Dysfunction, Right complications, Ventricular Remodeling physiology, Aortic Valve Stenosis diagnostic imaging, Aortic Valve Stenosis epidemiology
- Abstract
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.
- Published
- 2018
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24. Sono-activated persulfate oxidation of diclofenac: Degradation, kinetics, pathway and contribution of the different radicals involved.
- Author
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Monteagudo JM, El-Taliawy H, Durán A, Caro G, and Bester K
- Abstract
Degradation of a diclofenac aqueous solution was performed using persulfate anions activated by ultrasound. The objective of this study was to analyze different parameters affecting the diclofenac (DCF) removal reaction by the ultrasonic persulfate (US/PS) process and to evaluate the role played by various intermediate oxidative species such as hydroxyl- and sulfate radicals, superoxide radical anion or singlet oxygen in the removal process as well as to determine a possible reaction pathway. The effects of pH, initial persulfate anion concentration, ultrasonic amplitude and temperature on DCF degradation were examined. Sulfate and hydroxyl radicals were involved in the main reaction pathway of diclofenac. Diclofenac amide and three hydroxy-diclofenac isomers (3´-hydroxy diclofenac, 4´-hydroxy diclofenac and 5-hydroxy diclofenac) were identified as reaction intermediates., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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25. Photocatalytic degradation of aniline using an autonomous rotating drum reactor with both solar and UV-C artificial radiation.
- Author
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Durán A, Monteagudo JM, San Martín I, and Merino S
- Subjects
- Catalysis, Hydrogen Peroxide, Photochemistry, Sunlight, Titanium, Ultraviolet Rays, Aniline Compounds chemistry, Water Pollutants, Chemical chemistry
- Abstract
The aim of this work was to evaluate the performance of a novel self-autonomous reactor technology (capable of working with solar irradiation and artificial UV light) for water treatment using aniline as model compound. This new reactor design overcomes the problems of the external mass transfer effect and the accessibility to photons occurring in traditional reaction systems. The UV-light source is located inside the rotating quartz drums (where TiO
2 is immobilized), allowing light to easily reach the water and the TiO2 surface. Several processes (UV, H2 O2 , Solar, TiO2 , Solar/TiO2 , Solar/TiO2 /H2 O2 and UV/Solar/H2 O2 /TiO2 ) were tested. The synergy between Solar/H2 O2 and Solar/TiO2 processes was quantified to be 40.3% using the pseudo-first-order degradation rate. The apparent photonic efficiency, ζ, was also determined for evaluating light utilization. For the Solar/TiO2 /H2 O2 process, the efficiency was found to be practically constant (0.638-0.681%) when the film thickness is in the range of 1.67-3.87 μm. However, the efficiency increases up to 2.67% when artificial UV light was used in combination, confirming the efficient design of this installation. Thus, if needed, lamps can be switched on during cloudy days to improve the degradation rate of aniline and its mineralization. Under the optimal conditions selected for the Solar/TiO2 /H2 O2 process ([H2 O2 ] = 250 mg/L; pH = 4, [TiO2 ] = 0.65-1.25 mg/cm2 ), 89.6% of aniline is degraded in 120 min. If the lamps are switched on, aniline is completely degraded in 10 min, reaching 85% of mineralization in 120 min. TiO2 was re-used during 5 reaction cycles without apparent loss in activity (<2%). Quantification of hydroxyl radicals and dissolved oxygen allows a chemical-based explanation of the process. Finally, the UV/Solar/TiO2 /H2 O2 process was found to have lower operation costs than other systems described in literature (0.67 €/m3 )., (Copyright © 2018 Elsevier Ltd. All rights reserved.)- Published
- 2018
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26. Study of the intensification of solar photo-Fenton degradation of carbamazepine with ferrioxalate complexes and ultrasound.
- Author
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Expósito AJ, Monteagudo JM, Durán A, San Martín I, and González L
- Abstract
The intensification of the solar photo-Fenton system with ferrioxalate photoactive complexes and ultrasound applied to the mineralization of 15mg/L carbamazepine aqueous solution (CBZ) was evaluated. The experiments were carried out in a solar compound parabolic collector (CPC) pilot plant reactor coupled to an ultrasonic processor. The dynamic behavior of hydroxyl radicals generated under the different studied reaction systems was discussed. The initial concentrations of hydrogen peroxide and ferrous/oxalic acid and pH were found to be the most significant variables (32.79%, 25.98% and 26.04%, respectively). Under the selected optimal conditions ([H
2 O2 ]0 =150mg/L; [Fe2+ ]0 =2.5mg/L/[(COOH)2 ]0 =12.1mg/L; pH=5) CBZ was fully degraded after 5min and 80% of TOC was removed using a solar photo-Fenton system intensified with ferrioxalate (SPFF). However, no improvement in the mineralization using SPFF process combined with ultrasound was observed. More mild pH conditions could be used in the SPFF system if compared to the traditional photo-Fenton (pH 3) acidic systems. Finally, a possible reaction pathway for the mineralization of CBZ by the SPFF system was proposed and therein discussed., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2018
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27. Environmental sustainability of the solar photo-Fenton process for wastewater treatment and pharmaceuticals mineralization at semi-industrial scale.
- Author
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Foteinis S, Monteagudo JM, Durán A, and Chatzisymeon E
- Abstract
The environmental sustainability of a semi-industrial solar photo-Fenton reactor, treating real effluents emanating from a pharmaceutical laboratory, is assessed herein. The life cycle assessment/analysis (LCA) methodology was employed and real life cycle inventory (LCI) data was collected from a ferrioxalate-assisted homogeneous solar photo-Fenton wastewater treatment plant (WWTP), at Ciudad Real, Spain. Electricity was provided by photovoltaic (PV) panels in tandem with a battery bank, making the plant autonomous from the local grid. The effective treatment of 1m
3 of secondary-treated pharmaceutical wastewater, containing antipyrine, was used as a functional unit. The main environmental hotspot was identified to be the chemical reagents used to enhance treatment efficiency, mainly hydrogen peroxide (H2 O2 ) and to a smaller degree oxalic acid. On the other hand, land use, PV panels, battery units, compound parabolic collectors (CPC), tanks, pipes and pumps, as materials, had a low contribution, ranging from as little as 0.06% up to about 2% on the total CO2eq emissions. Overall, the solar photo-Fenton process was found to be a sustainable technology for treating wastewater containing micropollutants at semi-industrial level, since the total environmental footprint was found to be 2.71kgCO2 m-3 or 272mPtm-3 , using IPCC 2013 and ReCiPe impact assessment methods, respectively. A sensitivity analysis revealed that if the excess of solar power is fed back into the grid then the total environmental footprint is reduced. Depending on the amount of solar power fed back into the grid the process could have a near zero total environmental footprint., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2018
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28. Severe aortic stenosis patients with preserved ejection fraction according to flow and gradient classification: Prevalence and outcomes.
- Author
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González Gómez A, Fernández-Golfín C, Monteagudo JM, Izurieta C, Hinojar R, García A, Casas E, Jiménez-Nacher JJ, Moya JL, Ruiz S, and Zamorano JL
- Subjects
- Aged, Aged, 80 and over, Aortic Valve Stenosis mortality, Echocardiography, Doppler trends, Female, Follow-Up Studies, Humans, Male, Prevalence, Retrospective Studies, Treatment Outcome, Aortic Valve Stenosis diagnostic imaging, Aortic Valve Stenosis physiopathology, Fractional Flow Reserve, Myocardial physiology, Severity of Illness Index, Stroke Volume physiology
- Abstract
Background: Clinicians often encounter patients with apparently discordant echocardiographic findings, severe aortic stenosis (SAS) defined by aortic valve area (AVA) despite a low mean gradient. A new classification according to flow state and pressure gradient has been proposed. We sought to assess the prevalence, characteristics and outcomes of patients with asymptomatic SAS with preserved left-ventricular ejection fraction (LVEF) according to flow and gradient., Methods and Results: In total 442 patients with SAS (AVAi<0.6 cm2/m2) and LVEF ≥50% (mean age 80+11years, 54,5% female) were included. Patients were classified according to flow state (≥ or <35ml/m
2 ) and mean pressure gradient (≥ or <40mmHg): Low Flow/Low Gradient (LF/LG): 21.3%(n=94); Normal Flow/Low Gradient (NF/LG): 32.1%(n=142); Low Flow/High Gradient (LF/HG): 6.8%(n=30); Normal Flow/High Gradient (NF/HG): 39,8%(n=176). Mean follow-up time was 20.5months (SD=10.3). Primary combined endpoint was cardiovascular mortality and hospital admission for SAS related symptom, secondary endpoint was aortic valve replacement (AVR), comparing HG group to LF/LG group. During follow-up 17 (18%) of LF/LG patients and 21 (10.2%) of HG patients met the primary endpoint. A lower free of event survival (cardiovascular mortality and hospital admission) was observed in patients with LF/LG AS (Breslow, p=0.002). Significant differences were noted between groups with a lower AVR free survival in the LF/LG group compared to HG groups (Breslow, p=0.002)., Conclusions: Our study confirms the high prevalence and worse prognosis of LF/LG SAS. Clinicians must be aware of this entity to ensure appropriate patient management., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)- Published
- 2017
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29. Mineralization of aniline using hydroxyl/sulfate radical-based technology in a waterfall reactor.
- Author
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Durán A, Monteagudo JM, San Martín I, Amunategui FJ, and Patterson DA
- Subjects
- Aniline Compounds, Carbonates chemistry, Ferrous Compounds, Hydrogen Peroxide chemistry, Hydroxyl Radical chemistry, Oxidation-Reduction, Phenol chemistry, Phenols, Ultraviolet Rays, Sulfates chemistry, Waste Disposal, Fluid methods, Water Pollutants, Chemical chemistry
- Abstract
The aim of this work is to study the applicability of a UV/H
2 O2 process intensified with persulfate (PS) as a source of SO4 - radicals to efficiently mineralize a synthetic effluent containing aniline in a glass reactor arranged in a cascade configuration. pH conditions were studied and the concentration of PS was optimized. The synergism for aniline mineralization between the UV/H2 O2 process and the combined UV/H2 O2 /PS process was quantified in 10.1%. Aniline degradation reached 100% under the UV/H2O2/PS process after 20 min. Its mineralization is favored under acidic conditions and with the presence of persulfate (optimal conditions: 49% in 90 min; pH = 4; [PS] = 250 ppm). On the contrary, the worst conditions were found at pH = 11, since hydrogen peroxide decomposes and carbonates were formed increasing the scavenging effect. The different mechanisms involved (formulated from intermediates identified by mass spectrometry) confirm these results. Aniline was found to follow a degradation pathway where phenol is the main intermediate. The presence of sulfate radicals increases phenol degradation rate leading to a higher mineralization extent. Benzoquinone was identified as the main aromatic oxidation product of phenol, whereas succinic, 4-oxo-pentanoic, fumaric and oxalic acids were detected as aliphatic oxidation products for both UV/H2O2 and UV/H2O2/PS oxidation processes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
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30. Mitral-Aortic Flow Reversal in Cardiac Resynchronization Therapy: Coupling With Ejection and Impact of Variations in Atrioventricular Delay.
- Author
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Rodríguez Muñoz D, Moya Mur JL, Moreno J, Fernández-Golfín C, Franco E, Berlot B, Monteagudo JM, Matía Francés R, Hernández Madrid A, and Zamorano JL
- Subjects
- Aged, Aged, 80 and over, Aorta diagnostic imaging, Atrioventricular Node diagnostic imaging, Cardiomyopathies diagnosis, Cardiomyopathies physiopathology, Echocardiography, Doppler, Color, Echocardiography, Doppler, Pulsed, Female, Humans, Male, Middle Aged, Mitral Valve diagnostic imaging, Myocardial Perfusion Imaging methods, Prospective Studies, Regional Blood Flow, Spain, Time Factors, Treatment Outcome, Aorta physiopathology, Atrioventricular Node physiopathology, Cardiac Resynchronization Therapy methods, Cardiomyopathies therapy, Mitral Valve physiopathology, Stroke Volume, Ventricular Function, Left
- Abstract
Background: Flow entering the left ventricle is reversed toward the outflow tract through rotating reversal flow around the mitral valve. This was thought to facilitate early ejection, but had not been proved to date. We hypothesized that perfect coupling between reversal and ejection flow would occur at optimal atrioventricular delay (AVD), contributing to its hemodynamic superiority, and evaluated its applicability for AVD optimization., Methods and Results: Forty consecutive patients with cardiac resynchronization therapy underwent intracardiac flow analysis and AVD optimization. Reversal and ejection flow curves were studied. The presence and duration of reversal-ejection discontinuity were assessed for all programmed AVD. Reproducibility of each optimization method was evaluated through interobserver variability. Discontinuity between reversal and ejection flow was observed in all patients with longer than optimal AVD, increasing linearly with excess duration in AVD (linear R
2 =0.976, P <0.001). Longer discontinuities implied progressive decreases in pre-ejection flow velocity in the left ventricular outflow tract, with consequent loss of flow momentum. The equation optimal AVD=programmed AVD-[1.2(discontinuity duration)]+4 accurately predicted optimal AVD. Short AVD systematically compromised reversal flow because of premature ejection. Agreement over optimal AVD was superior when assessed by flow reversal method (intraclass correlation coefficient =0.931; P <0.001) over both iterative and aortic velocity-time integral methods., Conclusions: Perfect coupling between mitral-aortic flow reversal and ejection flow in the left ventricle occurs at optimal AVD. As a result, full blood momentum in the outflow tract is used to facilitate early ejection. This can be measured and provides a new method for AVD optimization., (© 2017 American Heart Association, Inc.)- Published
- 2017
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31. Dynamic behavior of hydroxyl radical in sono-photo-Fenton mineralization of synthetic municipal wastewater effluent containing antipyrine.
- Author
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Expósito AJ, Monteagudo JM, Durán A, and Fernández A
- Subjects
- Catalysis, Photochemical Processes, Antipyrine chemistry, Cities, Hydrogen Peroxide chemistry, Hydroxyl Radical chemistry, Iron chemistry, Minerals chemistry, Sonication, Wastewater chemistry
- Abstract
The aim of this study was to examine the kinetics of the different mechanisms (radical pathway, photolysis, molecular reaction with H
2 O2 and reaction with ultrasonically generated oxidative species) involved in the homogeneous sono-photoFenton (US/UV/H2 O2 /Fe) mineralization of antipyrine present in a synthetic municipal wastewater effluent (ASMWE). The dynamic behavior of hydroxyl (HO) radical generation and consumption in mineralization reaction under different systems was investigated by measuring hydroxyl radical concentration during the reaction. The overall mineralization process was optimized using a Central-Composite Experimental Design (CCED) with four variables (initial concentrations of H2 O2 and Fe(II), amplitude and pulse length). The response functions (pseudo-first order mineralization kinetic rate constants) were fitted using neural networks (NNs). Under the optimal conditions ([H2 O2 ]o =500mgL-1 , [Fe(II)]o =27mgL-1 , Amplitude (%)=20andPulse length=1), the TOC removal was 79% in 50min. The radical reaction in the bulk solution was found be the primary mineralization pathway (94.8%), followed by photolysis (3.65%), direct reaction with H2 O2 (0.86%), and reaction by ultrasonically generated oxidative species (0.64%). The role of the Fe catalyst on the radical reaction and the presence of refractory intermediates towards hydroxyl radical were also studied., (Copyright © 2016 Elsevier B.V. All rights reserved.)- Published
- 2017
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32. Antipyrine removal by TiO 2 photocatalysis based on spinning disc reactor technology.
- Author
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Expósito AJ, Patterson DA, Mansor WSW, Monteagudo JM, Emanuelsson E, Sanmartín I, and Durán A
- Subjects
- Catalysis, Humans, Photolysis, Ultraviolet Rays, Antipyrine chemistry, Titanium chemistry, Water Pollutants, Chemical chemistry, Water Purification methods
- Abstract
The photo-degradation of the emerging contaminant antipyrine (AP) was studied and optimized in a novel photocatalytic spinning disc reactor (SDR). A heterogeneous process (UV/H
2 O2 /TiO2 ) was used. TiO2 was immobilized on the surface of a glass disc using a sol-gel method. A factorial design of experiments followed by a Neural Networks fitting allowed the optimal conditions to be determined for treating 50 mg/L of AP. Under these conditions (pH = 4; [H2 O2 ]0 = 1500 mg/L; disc speed = 500 rpm; flowrate = 25 mL/s), AP was completely degraded in 120 min and regeneration of the disc allowed 10 cycles with no loss in efficiency. The value of the apparent volumetric rate constant was found to be 6.9·10-4 s-1 with no apparent mass transfer limitation. Based on the main intermediates identified, a mechanism is proposed for antipyrine photodegradation: Firstly, cleavage of the NN bond of penta-heterocycle leads to the formation of two aromatic acids and N-phenylpropanamide. An attack to the CN bond in the latter compound produces benzenamine. Finally, the phenyl ring of the aromatic intermediates are opened and molecular organic acids are formed., (Copyright © 2016 Elsevier Ltd. All rights reserved.)- Published
- 2017
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33. A novel combined solar pasteurizer/TiO 2 continuous-flow reactor for decontamination and disinfection of drinking water.
- Author
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Monteagudo JM, Durán A, Martín IS, and Acevedo AM
- Subjects
- Catalysis, Decontamination, Disinfection methods, Escherichia coli drug effects, Photochemical Processes, Titanium chemistry, Drinking Water chemistry, Sunlight, Water Purification methods
- Abstract
A new combined solar plant including an annular continuous-flow compound parabolic collector (CPC) reactor and a pasteurization system was designed, built, and tested for simultaneous drinking water disinfection and chemical decontamination. The plant did not use pumps and had no electricity costs. First, water continuously flowed through the CPC reactor and then entered the pasteurizer. The temperature and water flow from the plant effluent were controlled by a thermostatic valve located at the pasteurizer outlet that opened at 80 °C. The pasteurization process was simulated by studying the effect of heat treatment on the death kinetic parameters (D and z values) of Escherichia coli K12 (CECT 4624). 99.1% bacteria photo-inactivation was reached in the TiO
2 -CPC system (0.60 mg cm-2 TiO2 ), and chemical decontamination in terms of antipyrine degradation increased with increasing residence time in the TiO2 -CPC system, reaching 70% degradation. The generation of hydroxyl radicals (between 100 and 400 nmol L-1 ) was a key factor in the CPC system efficiency. Total thermal bacteria inactivation was attained after pasteurization in all cases. Chemical degradation and bacterial photo-inactivation in the TiO2 -CPC system were improved with the addition of 150 mg L-1 of H2 O2 , which generated approximately 2000-2300 nmol L-1 of HO● radicals. Finally, chemical degradation and bacterial photo-inactivation kinetic modelling in the annular CPC photoreactor were evaluated. The effect of the superficial liquid velocity on the overall rate constant was also studied. Both antipyrine degradation and E. coli photo-inactivation were found to be controlled by the catalyst surface reaction rate., (Copyright © 2016 Elsevier Ltd. All rights reserved.)- Published
- 2017
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34. Sono-photo-degradation of carbamazepine in a thin falling film reactor: Operation costs in pilot plant.
- Author
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Expósito AJ, Patterson DA, Monteagudo JM, and Durán A
- Subjects
- Hydrogen Peroxide chemistry, Iron chemistry, Pilot Projects, Ultraviolet Rays, Carbamazepine chemistry, Carbamazepine isolation & purification, Costs and Cost Analysis, Photolysis, Ultrasonic Waves
- Abstract
The photo-Fenton degradation of carbamazepine (CBZ) assisted with ultrasound radiation (US/UV/H
2 O2 /Fe) was tested in a lab thin film reactor allowing high TOC removals (89% in 35min). The synergism between the UV process and the sonolytic one was quantified as 55.2%. To test the applicability of this reactor for industrial purposes, the sono-photo-degradation of CBZ was also tested in a thin film pilot plant reactor and compared with a 28L UV-C conventional pilot plant and with a solar Collector Parabolic Compound (CPC). At a pilot plant scale, a US/UV/H2 O2 /Fe process reaching 60% of mineralization would cost 2.1 and 3.8€/m3 for the conventional and thin film plant respectively. The use of ultrasound (US) produces an extra generation of hydroxyl radicals, thus increasing the mineralization rate. In the solar process, electric consumption accounts for a maximum of 33% of total costs. Thus, for a TOC removal of 80%, the cost of this treatment is about 1.36€/m3 . However, the efficiency of the solar installation decreases in cloudy days and cannot be used during night, so that a limited flow rate can be treated., (Copyright © 2016 Elsevier B.V. All rights reserved.)- Published
- 2017
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- View/download PDF
35. Solar photo-degradation of a pharmaceutical wastewater effluent in a semi-industrial autonomous plant.
- Author
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Expósito AJ, Durán A, Monteagudo JM, and Acevedo A
- Subjects
- Drug Industry, Hydrogen Peroxide chemistry, Iron chemistry, Oxalates chemistry, Pharmaceutical Preparations radiation effects, Spain, Water Pollutants, Chemical radiation effects, Pharmaceutical Preparations analysis, Sunlight, Waste Disposal, Fluid methods, Wastewater chemistry, Water Pollutants, Chemical analysis, Water Purification methods
- Abstract
An industrial wastewater effluent coming from a pharmaceutical laboratory has been treated in a semi-industrial autonomous solar compound parabolic collector (CPC) plant. A photo-Fenton process assisted with ferrioxalate has been used. Up to 79% of TOC can be removed in 2 h depending on initial conditions when treating an aqueous effluent containing up to 400 ppm of initial organic carbon concentration (TOC). An initial ratio of Fe(II)/TOC higher than 0.5 guarantees a high removal. It can be seen that most of TOC removal occurs early in the first hour of reaction. After this time, mineralization was very slow, although H2O2 was still present in solution. Indeed it decomposed to form oxygen in inefficient reactions. It is clear that remaining TOC was mainly due to the presence of acetates which are difficult to degrade., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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36. Application of activated persulfate for removal of intermediates from antipyrine wastewater degradation refractory towards hydroxyl radical.
- Author
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Monteagudo JM, Durán A, Latorre J, and Expósito AJ
- Abstract
Complete mineralisation of reaction intermediates refractory towards hydroxyl radical, generated from a previous ineffective degradation of urban wastewater containing antipyrine by HO-mediated sono-photo-Fenton reaction, has been attained using persulfate anions simultaneously activated by heat energy (thermally, ultrasound) and UV-C light. The SO4(-)-based mineralisation process enables another reaction pathway generating more easy degradable derivatives. The influences of the initial concentration of persulfate, ultrasound amplitude, temperature and the reaction time in the previous HO-based previous oxidation on the mineralisation degree were studied by using a Central-Composite Experimental Design. Under optimal conditions ([S2O8(2-)]o=1200mgL(-1), temperature=50°C, amplitude=10%, pH 2.8, HO-based reaction time=25min) practically complete degradation was achieved in approximately 120min. The contribution of HO and SO4(-) radicals in this system was also evaluated. The presence of chloride ion in urban wastewater can benefit the oxidation of acetate by sulfate radical. Results demonstrated that this activated persulfate-based oxidation system is a potential alternative to degrade intermediate compounds, which are refractory against hydroxyl radicals, generated in Advanced Oxidation Processes used to treat wastewater containing emerging contaminants such as antipyrine., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
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37. Mineralization of wastewater from the pharmaceutical industry containing chloride ions by UV photolysis of H2O2/Fe(II) and ultrasonic irradiation.
- Author
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Monteagudo JM, Durán A, and San Martín I
- Subjects
- Chlorides chemistry, Ferrous Compounds chemistry, Hydrogen Peroxide chemistry, Hydroxyl Radical chemistry, Oxidation-Reduction, Photolysis, Ultrasonics, Wastewater chemistry, Drug Industry, Ferrous Compounds radiation effects, Hydrogen Peroxide radiation effects, Ultraviolet Rays, Waste Disposal, Fluid methods, Water Pollutants, Chemical chemistry
- Abstract
The mineralization of pharmaceutical wastewater containing chloride ions using a UV/H2O2/Fe(II) process was studied. The addition of Fe(II) to the UV/H2O2 system did not improve the degradation efficiency due to inhibition of the photo-Fenton reaction, at acid pH, in the presence of chloride ions in these wastewaters. The increase of pH from 2 to 7 increased the degree of mineralization under UV photolysis of H2O2 because more HO radicals are available by HOCl dissociation reaction. Under the selected operation conditions ([H2O2]o = 11,500 ppm, [Fe(II)] = 0 ppm, [TOC]o = 125 ppm and pH = 7), 100% of TOC removal was attained in 120 min. A significant synergistic effect of combining photolysis (UV/H2O2) and sonolysis was observed. Sonophotolysis (UV/H2O2/ultrasound) technique significantly increased the degree of mineralization (100% TOC removal in 90 min using 6500 ppm H2O2) when compared with each individual process. Sonochemical reaction was favored by the presence of chloride ions since the concentration of contaminants at the gas-liquid interface increased. Free radicals reaction was the controlling mechanism in the UV/H2O2/ultrasound system. HO radicals were the main oxidative intermediate species in the process, although hydroperoxyl radicals (HO2) also played a role. The contribution of thermal-pyrolytic reaction (in gas-phase) to sonophotolysis process was negligible., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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38. Solar photo-Fenton mineralization of antipyrine in aqueous solution.
- Author
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Durán A, Monteagudo JM, Sanmartín I, and Carrasco A
- Subjects
- Antipyrine radiation effects, Neural Networks, Computer, Oxalates chemistry, Oxidants, Photochemical, Pilot Projects, Ultraviolet Rays, Water Pollutants, Chemical radiation effects, Water Pollution analysis, Water Pollution prevention & control, Water Purification methods, Antipyrine chemistry, Oxidation-Reduction, Water Pollutants, Chemical chemistry
- Abstract
The mineralization of an aqueous solution of antipyrine (C11H12N2O), an emerging contaminant, using a solar photocatalytic oxidation process assisted with ferrioxalate was evaluated in a compound parabolic collector (CPC) pilot plant. Under the selected operating conditions ([H2O2] = 250 ppm, [Fe] = 14 ppm, pH = 2.7, and [(COOH)2·2H2O] = 80 ppm), 60% of TOC is removed just 5 min after treating an aqueous solution containing 50 ppm of antipyrine. The addition of oxalic acid up to a maximum concentration of 80 ppm significantly increases the mineralization rate during the first 15 min of the reaction. The synergism between the solar and dark H2O2/ferrioxalate process was quantified at 79%, calculated from the pseudo first-order mineralization rate constants. The operational costs due to the consumption of electrical energy, reagents and catalysts were calculated from the optimal conditions and compared with a novel sono-photocatalytic process using artificial UV-light. The results showed that the ferrioxalate-assisted solar photo-Fenton process was economically feasible, being able to achieve up to 60% mineralization with a total cost of 4.5 cent €/g TOC removed (1.1 €/m(3))., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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39. Optimization of pharmaceutical wastewater treatment by solar/ferrioxalate photo-catalysis.
- Author
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Monteagudo JM, Durán A, Culebradas R, San Martín I, and Carnicer A
- Subjects
- Catalysis, Costs and Cost Analysis, Equipment Design, Hydrogen Peroxide chemistry, Industrial Waste, Neural Networks, Computer, Oxalic Acid chemistry, Oxidation-Reduction, Photochemistry methods, Solar Energy, Sunlight, Temperature, Waste Disposal, Fluid economics, Waste Disposal, Fluid instrumentation, Drug Industry, Oxalates chemistry, Waste Disposal, Fluid methods, Wastewater chemistry
- Abstract
The degradation of a pharmaceutical wastewater using a ferrioxalate-assisted solar/photo-Fenton system has been studied. The photochemical reaction was carried out in a pilot plant consisting of a compound parabolic collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and Neuronal Networks that included the following variables: initial concentrations of H2O2, catalyst Fe (II) and oxalic acid (H2C2O4), temperature and solar power. Under optimal conditions, 84% TOC (Total Organic Carbon) removal was achieved in 115 min. Oxalic acid had a positive effect on mineralization when solar power was above 30 W m(-2). The minimum amount of H2O2 to degrade 1 mol of TOC was found to be 3.57 mol. Both the H2O2 conversion efficiency and the degree of mineralization were highest when the oxalic/Fe(II) initial molar relation was close to 3. HO radicals were the main oxidative intermediate species in the process, although hydroperoxyl radicals (HO(2)(·)) also played a role., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
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40. Homogeneous sonophotolysis of food processing industry wastewater: Study of synergistic effects, mineralization and toxicity removal.
- Author
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Durán A, Monteagudo JM, Sanmartín I, and Gómez P
- Subjects
- Food Industry, Hazardous Substances isolation & purification, Industrial Waste, Minerals chemistry, Wastewater chemistry
- Abstract
The mineralization of industrial wastewater coming from food industry using an emerging homogeneous sonophotolytic oxidation process was evaluated as an alternative to or a rapid pretreatment step for conventional anaerobic digestion with the aim of considerably reducing the total treatment time. At the selected operation conditions ([H(2)O(2)]=11,750ppm, pH=8, amplitude=50%, pulse length (cycles)=1), 60% of TOC is removed after 60min and 98% after 180min when treating an industrial effluent with 2114ppm of total organic carbon (TOC). This process removed completely the toxicity generated during storing or due to intermediate compounds. An important synergistic effect between sonolysis and photolysis (H(2)O(2)/UV) was observed. Thus the sonophotolysis (ultrasound/H(2)O(2)/UV) technique significantly increases TOC removal when compared with each individual process. Finally, a preliminary economical analysis confirms that the sono-photolysis with H(2)O(2) and pretreated water is a profitable system when compared with the same process without using ultrasound waves and with no pretreatment., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
41. Photocatalytic treatment of an industrial effluent using artificial and solar UV radiation: an operational cost study on a pilot plant scale.
- Author
-
Durán A, Monteagudo JM, and San Martín I
- Subjects
- Pilot Projects, Waste Disposal, Fluid economics, Hydrogen Peroxide chemistry, Industrial Waste, Iron chemistry, Photolysis, Ultraviolet Rays, Waste Disposal, Fluid methods
- Abstract
The aim of this work was to study the operation costs of treating a real effluent from an integrated gasification combined cycle (IGCC) power station located in Spain. The study compares different homogeneous photocatalytic processes on a pilot plant scale using different types of radiation (artificial UV or solar UV with a compound parabolic collector). The efficiency of the processes was evaluated by an analysis of the total organic carbon (TOC) removed. The following processes were considered in the study: (i) a photo-Fenton process at an artificial UV pilot plant (with the initial addition of H(2)O(2)), (ii) a modified photo-Fenton process with continuous addition of H(2)O(2) and O(2) to the system and (iii) a ferrioxalate-assisted solar photo-Fenton process at a compound parabolic collector (CPC) pilot plant. The efficiency of these processes in degrading pollutants has been studied previously, and the results obtained in each of those studies have been published elsewhere. The operational costs due to the consumption of electrical energy, reagents and catalysts were calculated from the optimal conditions of each process. The results showed that the solar photo-Fenton system was economically feasible, being able to achieve up to 75% mineralization with a total cost of 6 €/m(3), which can be reduced to 3.6 €/m(3) by subtracting the electrical costs because the IGCC plant is self-sufficient in terms of energy., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
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42. Optimization of the mineralization of a mixture of phenolic pollutants under a ferrioxalate-induced solar photo-Fenton process.
- Author
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Monteagudo JM, Durán A, Aguirre M, and San Martín I
- Subjects
- Algorithms, Chromatography, High Pressure Liquid, Hydrogen Peroxide analysis, Hydrogen-Ion Concentration, Kinetics, Neural Networks, Computer, Oxalates analysis, Oxidation-Reduction, Oxygen analysis, Photochemistry, Solar System, Spectrophotometry, Ultraviolet, Temperature, Environmental Pollutants analysis, Hydrogen Peroxide chemistry, Hydroxybenzoates analysis, Iron chemistry, Minerals analysis, Oxalates chemistry, Solar Energy
- Abstract
The mineralization of solutions containing a mixture of three phenolic compounds, gallic, p-coumaric and protocatechuic acids, in a ferrioxalate-induced solar photo-Fenton process was investigated. The reactions were carried out in a pilot plant consisting of a compound parabolic collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and neuronal networks that included the following variables: pH, temperature, solar power, air flow and initial concentrations of H(2)O(2), Fe(II) and oxalic acid. Under optimal conditions, total elimination of the original compounds and 94% TOC removal of the mixture were achieved in 5 and 194 min, respectively. pH and initial concentrations of H(2)O(2) and Fe(II) were the most significant factors affecting the mixture mineralization. The molar correlation between consumed hydrogen peroxide and removed TOC was always between 1 and 3. A detailed analysis of the reaction was presented. The values of the pseudo-first-order mineralization kinetic rate constant, k(TOC), increased as initial Fe(II) and H(2)O(2) concentrations and temperature increased. The optimum pH value also slightly increased with greater Fe(II) and hydrogen peroxide concentrations but decreased when temperature increased. OH and O(2)(-) radicals were the main oxidative intermediate species in the process, although singlet oxygen ((1)O(2)) also played a role in the mineralization reaction., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
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43. Mineralization of integrated gasification combined-cycle power-station wastewater effluent by a photo-Fenton process.
- Author
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Durán A, Monteagudo JM, San Martín I, and Aguirre M
- Subjects
- Air, Hydrogen-Ion Concentration, Neural Networks, Computer, Pilot Projects, Power Plants, Ultraviolet Rays, Hydrogen Peroxide chemistry, Industrial Waste analysis, Iron chemistry, Waste Disposal, Fluid methods, Water Pollution, Chemical prevention & control
- Abstract
The aim of this work was to study the mineralization of wastewater effluent from an integrated-gasification combined-cycle (IGCC) power station sited in Spain to meet the requirements of future environmental legislation. This study was done in a pilot plant using a homogeneous photo-Fenton oxidation process with continuous addition of H(2)O(2) and air to the system. The mineralization process was found to follow pseudo-first-order kinetics. Experimental kinetic constants were fitted using neural networks (NNs). The NNs model reproduced the experimental data to within a 90% confidence level and allowed the simulation of the process for any values of the parameters within the experimental range studied. At the optimum conditions (H(2)O(2) flow rate=120 mL/h, [Fe(II)]=7.6 mg/L, pH=3.75 and air flow rate=1 m(3)/h), a 90% mineralization was achieved in 150 min. Determination of the hydrogen peroxide consumed and remaining in the water revealed that 1.2 mol of H(2)O(2) was consumed per each mol of total organic carbon removed from solution. This result confirmed that an excess of dissolved H(2)O(2) was needed to achieve high mineralization rates, so continuous addition of peroxide is recommended for industrial application of this process. Air flow slightly improved the mineralization rate due to the formation of peroxo-organic radicals which enhanced the oxidation process., (2010 Elsevier Ltd. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
44. Photocatalytic treatment of IGCC power station effluents in a UV-pilot plant.
- Author
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Durán A, Monteagudo JM, San Martín I, and Sánchez-Romero R
- Subjects
- Catalysis, Conservation of Natural Resources legislation & jurisprudence, Ferrous Compounds, Hydrogen Peroxide, Hydrogen-Ion Concentration, Oxidation-Reduction, Pilot Projects, Temperature, Waste Management legislation & jurisprudence, Photochemical Processes, Ultraviolet Rays, Waste Management methods
- Abstract
The aim of this work is to improve the quality of water effluents coming from an Integrated Gasification Combined Cycle (IGCC) power station to meet with future environmental legislation. This study has been made using an homogeneous photocatalytic oxidation process (UV/Fe(II)/H(2)O(2)) in a pilot plant. The efficiency of the process was determined from the analysis of the following parameters: cyanides, formates and TOC content. In the first stage, a factorial experimental design allowed to determine the influence of operation variables (initial concentration of H(2)O(2) and Fe(II), pH and temperature) on the degradation kinetics. pH was always kept in a value >9.5 during cyanides destruction to avoid gaseous HCN formation and lowered later to enhance formates degradation. Experimental kinetic constants were fitted using neural networks (NNs). Under the optimum conditions ([H(2)O(2)]=1700 ppm, [Fe(II)]=2 ppm, pH 2 after cyanides destruction, and T=30 degrees C), it is possible to degrade 100% of cyanides in 15 min and 76% of formates in 120 min. The use of an homogeneous process with UV light can offer an economical and practical alternative to heterogeneous photocatalysis for the destruction of environmental pollutants present in thermoelectric power stations effluents, since it can treat very high flowrates using a lower H(2)O(2) concentration. Furthermore, it does not require additional operations to recover the solid catalyst and regenerate it due to deactivation as occurs in heterogeneous catalysis.
- Published
- 2009
- Full Text
- View/download PDF
45. Treatment of IGCC power station effluents by physico-chemical and advanced oxidation processes.
- Author
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Durán A, Monteagudo JM, Sanmartín I, García-Peña F, and Coca P
- Subjects
- Cyanides chemistry, Hydrogen Peroxide chemistry, Oxidants, Photochemical chemistry, Oxidation-Reduction, Ultraviolet Rays, Waste Disposal, Fluid instrumentation, Industrial Waste analysis, Power Plants, Waste Disposal, Fluid methods, Water Purification methods
- Abstract
The aim of this work was to improve the quality of aqueous effluents coming from the Gasification Unit in an Integrated Gasification Combined Cycle (IGCC) Thermoelectric Power Station, with the purpose of fulfilling the future more demanding normative. To this end, an integral wastewater treatment including coagulation, flocculation, neutralization, photocatalytic oxidation, and ion-exchange has been studied. A final scheme has been proposed to remove pollutants. All the parameters of the treated wastewater are below pouring specifications. In the first stage, the wastewater was treated with CaCl2 (optimal dose=11 g CaCl2/g F-) as coagulant and a commercial anionic polyelectrolyte (optimal dose=0.02 g/g F-) as flocculant to remove fluoride ions (99%) and suspended solids (92%). The water was then neutralized, improving the degree of transmission of ultraviolet light, allowing the faster photo-degradation of pollutants. The photochemical study included different systems (H2O2, UV/H2O2, Fenton, Fenton-like, UV/Fenton, UV/Fenton-like and UV/H2O2/O2). In the Fenton-like system, the influence of two parameters (initial concentration of H2O2 and amount of Cu(II)) on the degradation of cyanide and formate (taken as the reference of the process) was studied. Experimental results were fit using neural networks (NNs). Results showed that the photocatalytic process was effective for total cyanide destruction after 60 min, while 180 min was needed to remove 80% of formates. However, a more simple system with UV/H2O2/O2 yields similar results and is preferred for industrial application due to fewer complications. Finally, an ion-exchange process with Amberlite IRA-420 was proposed to remove the excess of chlorides added as a consequence of the initial coagulation process.
- Published
- 2009
- Full Text
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46. Solar TiO2-assisted photocatalytic degradation of IGCC power station effluents using a Fresnel lens.
- Author
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Monteagudo JM, Durán A, Guerra J, García-Peña F, and Coca P
- Subjects
- Catalysis, Hydrogen-Ion Concentration, Photochemistry, Industrial Waste, Power Plants, Sunlight, Titanium chemistry
- Abstract
The heterogeneous TiO2 assisted photocatalytic degradation of wastewater from a thermoelectric power station under concentrated solar light irradiation using a Fresnel lens has been studied. The efficiency of photocatalytic degradation was determined from the analysis of cyanide and formate removal. Firstly, the influence of the initial concentration of H2O2 and TiO2 on the degradation kinetics of cyanides and formates was studied based on a factorial experimental design. Experimental kinetic constants were fitted using neural networks. Results showed that the photocatalytic process was effective for cyanides destruction (mainly following a molecular mechanism), whereas most of formates (degraded mainly via a radical path) remained unaffected. Finally, to improve formates degradation, the effect of lowering pH on their degradation rate was evaluated after complete cyanide destruction. The photooxidation efficiency of formates reaches a maximum at pH around 5-6. Above pH 6, formate anion is subjected to electrostatic repulsion with the negative surface of TiO2. At pH<4.5, formate adsorption and photon absorption are reduced due to some catalyst agglomeration.
- Published
- 2008
- Full Text
- View/download PDF
47. Photocatalytic degradation of pollutants from Elcogas IGCC power station effluents.
- Author
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Durán A, Monteagudo JM, San Martín I, García-Peña F, and Coca P
- Subjects
- Catalysis, Cyanides radiation effects, Formates radiation effects, Hydrogen Peroxide chemistry, Hydrogen-Ion Concentration, Industrial Waste, Neural Networks, Computer, Photochemistry, Power Plants, Titanium chemistry, Ultraviolet Rays, Waste Disposal, Fluid methods, Water Pollutants, Chemical radiation effects, Water Purification methods, Zinc Oxide chemistry, Cyanides chemistry, Formates chemistry, Water Pollutants, Chemical chemistry
- Abstract
The aim of this work is to improve the quality of water effluents coming from Elcogas IGCC power station (Puertollano, Spain) with the purpose of fulfilling future more demanding normative, using heterogeneous photocatalytic oxidation processes (UV/H(2)O(2)/TiO(2) or ZnO). The efficiency of photocatalytic degradation for the different catalysts (TiO(2) and ZnO) was determined from the analysis of the following parameters: cyanides, formates and ammonia content. In a first stage, the influence of two parameters (initial concentration of H(2)O(2) and amount of catalyst) on the degradation kinetics of cyanides and formates was studied based on a factorial experimental design. pH was always kept in a value >9.5 to avoid gaseous HCN formation. The degradation of cyanides and formates was found to follow pseudo-first order kinetics. Experimental kinetic constants were fitted using neural networks (NNs). The mathematical model reproduces experimental data within 90% of confidence and allows the simulation of the process for any value of parameters in the experimental range studied. Moreover, a measure of the saliency of the input variables was made based upon the connection weights of the neural networks, allowing the analysis of the relative relevance of each variable with respect to the others. Results showed that the photocatalytic process was effective, being the degradation rate of cyanides about five times higher when compared to removal of formates. Finally, the effect of lowering pH on the degradation of formates was evaluated after complete cyanides destruction was reached (10 min of reaction). Under the optimum conditions (pH 5.2, [H(2)O(2)]=40 g/l; [TiO(2)]=2g/l), 100% of cyanides and 92% of initial NH(3) concentration are degraded after 10 min, whereas 35 min are needed to degrade 98% of formates.
- Published
- 2007
- Full Text
- View/download PDF
48. Solar photocatalytic degradation of reactive blue 4 using a Fresnel lens.
- Author
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Durán A and Monteagudo JM
- Subjects
- Hydrogen Peroxide chemistry, Hydrogen-Ion Concentration, Iron chemistry, Photochemistry instrumentation, Triazines radiation effects, Water Pollutants, Chemical chemistry, Water Pollutants, Chemical radiation effects, Water Purification methods, Photochemistry methods, Sunlight, Triazines chemistry
- Abstract
The heterogeneous photocatalytic degradation of reactive blue 4 dye (RB4) solutions under Fenton reagent and TiO(2) assisted by concentrated solar light irradiation using a Fresnel lens has been studied. Multivariate experimental design was applied to study the kinetic process. The efficiency of photocatalytic degradation was determined from the analysis of color and total organic carbon (TOC) removal. Factorial experimental design allowed to determine the influence of four parameters (pH and initial concentrations of TiO(2), Fe(II) and H(2)O(2)) on the value of the decoloration kinetic rate constant. Experimental data were fitted using neural networks (NNs). The mathematical model reproduces experimental data within 86% of confidence and allows the simulation of the process for any value of parameters in the experimental range studied. Also, a measure of the saliency of the input variables was made based upon the connection weights of the neural networks, allowing the analysis of the relative relevance of each variable with respect to the others. Results showed that acidic pHs (pH=3.6) are preferred for the complete dye decoloration. The optimum catalyst concentration is 1.2g TiO(2)/l. The use of a low cost catalyst and its activation using a Fresnel lens to concentrate solar energy significantly accelerates the degradation process when compared with direct solar radiation alone and can offer an economical and practical alternative for the destruction of environmental organic compounds.
- Published
- 2007
- Full Text
- View/download PDF
49. Fresnel lens to concentrate solar energy for the photocatalytic decoloration and mineralization of orange II in aqueous solution.
- Author
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Monteagudo JM and Durán A
- Subjects
- Azo Compounds chemistry, Benzenesulfonates chemistry, Carbon analysis, Catalysis, Color, Coloring Agents chemistry, Hydrogen Peroxide chemistry, Hydrogen-Ion Concentration, Lenses, Photochemistry, Solar Energy, Titanium chemistry, Waste Disposal, Fluid, Water Pollutants, Chemical chemistry, Water Purification methods, Azo Compounds radiation effects, Benzenesulfonates radiation effects, Coloring Agents radiation effects, Sunlight, Ultraviolet Rays, Water Pollutants, Chemical radiation effects
- Abstract
The decoloration and mineralization of the azo dye orange II under conditions of artificial ultraviolet light and solar energy concentrated by a Fresnel lens in the presence of hydrogen peroxide and TiO(2)-P25 was studied. A comparative study to demonstrate the viability of this solar installation was done to establish if the concentration reached in the focus of the Fresnel lens was enough to improve the photocatalytic degradation reaction. The degradation efficiency was higher when the photolysis was carried out under concentrated solar energy irradiation as compared to UV light source in the presence of an electron acceptor such us H(2)O(2) and the catalyst TiO(2). The effect of hydrogen peroxide, pH and catalyst concentration was also determined. The increase of H(2)O(2) concentration until a critical value (14.7 mM) increased both the solar and artificial UV oxidation reaction rate by generating hydroxyl radicals and inhibiting the (e(-)/h(+)) pair recombination, but the excess of hydrogen peroxide decreases the oxidation rate acting as a radical or hole scavenger and reacting with TiO(2) to form peroxo-compounds, contributing to the inhibition of the reaction. The use of the response surface methodology allowed to fit the optimal values of the parameters pH and catalyst concentration leading to the total solar degradation of orange II. The optimal pH range was 4.5-5.5 close to the zero point charge of TiO(2) depending on surface charge of catalyst and dye ionization state. Dosage of catalyst higher than 1.1 gl(-1) decreases the degradation efficiency due to a decrease of light penetration.
- Published
- 2006
- Full Text
- View/download PDF
50. Fenton's oxidation of food processing wastewater components. Kinetic modeling of protocatechuic acid degradation.
- Author
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Rivas FJ, Frades J, Alonso MA, Montoya C, and Monteagudo JM
- Subjects
- Catalysis, Hydrogen Peroxide chemistry, Iron, Kinetics, Oxidation-Reduction, Temperature, Food Industry, Hydroxybenzoates chemistry, Industrial Waste analysis
- Abstract
The oxidation of protocatechuic acid (PA), a typical phenol-type compound present in food processing wastewater, has been carried out by means of Fenton's reagent. Both the H2O2 and Fe(II) initial concentrations increase the PA degradation rate. Temperature also enhances the PA conversion when raised from 283 to 313 K, a further increase to 323 K results in a lower PA removal. Increasing the PA initial concentration leads to a decrease of conversion values but an opposite effect in terms of removal rate. pH values in the range 3-4 resulted in the total inhibition of the oxidation process. Similar PA depletion rates were experienced regardless of the oxidation state of the catalyst (ferrous or ferric iron). Additionally, an attempt based on the classic Fenton's chemistry plus some other stages accounting for the Fe(II) regeneration from Fe(III) and the inefficient H2O2 decomposition was conducted to model the process.
- Published
- 2005
- Full Text
- View/download PDF
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