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1.
J Thorac Cardiovasc Surg ; 147(3): 1021-8, 1029.e1-2, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24342900

RESUMEN

OBJECTIVE: The impact of paravalvular aortic regurgitation (PAR) on hemodynamic performance after transcatheter aortic valve implantation (TAVI) remains disputable. Common parameters such as the diastolic blood pressure or the blood pressure amplitude do not provide reproducible results. The aim of our study was to evaluate the impact of PAR on hemodynamics and outcome using the relative amplitude index (RAI). METHODS: PAR was prospectively evaluated by echocardiography before discharge in 110 patients. The RAI was calculated according to the formula: RAI = [(Post-TAVI BP amplitude)/(Post-TAVI SBP) - (Pre-TAVI BP amplitude)/(Pre-TAVI SBP)] × 100%, where BP is blood pressure and SBP is systolic blood pressure. Correlations of increased RAI with perioperative outcome were investigated and factors influencing mortality were isolated. RESULTS: The incidence of moderate and severe PAR after TAVI was 9% and 1%, respectively. Diastolic pressure or post-TAVI amplitude did not correlate to perioperative outcome. RAI increased from 2 when PAR was <2+ to 7 when PAR was ≥2+ (P = .006). A cut-off value of RAI ≥14 was associated with increased perioperative mortality (29 vs 5%; P = .013) and acute renal injury requiring dialysis (71 vs 18%; P = .001). RAI ≥14 was also associated with higher follow-up mortality at 1 year (57 vs 16%; P = .007). RAI ≥14 (odds ratio [OR], 3.390; 95% confidence interval [CI], 1.6-7.194; P = .00146), PAR ≥2+ (OR, 4.717; 95% CI, 1.828-12.195; P = .00135), and perioperative renal replacement therapy (OR, 12.820; 95% CI, 5.181-31.250; P = .00031) were found to be independent predictors of mortality at 1 year. CONCLUSIONS: The RAI is a useful tool to predict perioperative and 1-year outcome in patients with PAR after TAVI.


Asunto(s)
Insuficiencia de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/terapia , Cateterismo Cardíaco/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Hemodinámica , Anciano , Anciano de 80 o más Años , Insuficiencia de la Válvula Aórtica/epidemiología , Insuficiencia de la Válvula Aórtica/mortalidad , Insuficiencia de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/fisiopatología , Austria/epidemiología , Presión Sanguínea , Cateterismo Cardíaco/mortalidad , Distribución de Chi-Cuadrado , Femenino , Implantación de Prótesis de Válvulas Cardíacas/métodos , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Humanos , Incidencia , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Sístole , Factores de Tiempo , Resultado del Tratamiento
4.
Waste Manag ; 24(6): 581-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15219916

RESUMEN

In this work, the impact of moisture on the volatility of heavy metals present in municipal solid wastes (MSW) in a laboratory scale simulated incinerator was studied, using synthetic waste consisting of 5.4 g of wood powder, 2.6 g lava, 1.9 polythene, 0.19 g polyvinyl chloride, and a given quantity of water and heavy metals represented by lead, zinc and copper in forms of metallic, chlorides and oxides. It is found that the presence of high moisture in MSW will greatly reduce the volatilization of heavy metals in MSW in the incineration process. The volatilization behavior of chlorides, oxides and the metallic species with respect to the effect of moistures is quite different. For copper, the presence of moisture in MSW depresses the volatilization of oxides, and increases that of chloride and the metallic species, while in contrast, the volatilization of both lead and zinc is always depressed by the presence of moisture in MSW, regardless of the chemical forms used. The chemical mechanisms, which govern the volatilization behaviors of different chemical forms in the incineration process, are proposed. Hydrolysis, dewatering of hydrolyzed species, sublimation, chemical transformation of less volatiles to more volatiles or reverse, may participate in and affect the volatilization of heavy metals in MSW.


Asunto(s)
Contaminantes Atmosféricos/análisis , Incineración , Metales Pesados/análisis , Metales Pesados/química , Modelos Teóricos , Hidrólisis , Volatilización , Agua/química
5.
Adv Space Res ; 31(1): 201-10, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12580172

RESUMEN

The C.E.B.A.S. MINI-MODULE is the miniaturized space flight version of the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.). It fits into a large middeck locker tray and is scheduled to be flown in the STS 85 and in the NEUROLAB missions. Its volume is about 9 liters and it consists of two animal tanks, a plant cultivator, and a bacteria filter in a monolithic design. An external sensor unit is connected to a data acquisition/control unit. The system integrates its own biological life support. The CO2 exhaled by the consumers (fishes, snails, microorganisms) is assimilated by water plants (Ceratophyllum demersum) which provide them with oxygen. The products of biomass degradation and excretion (mainly ammonia ions) are converted by bacteria into nitrite and nitrate. The latter is taken up by the plants as a nitrogen source together with other ions like phosphate. The plants convert light energy into chemical energy and their illumination is regulated via the oxygen concentration in the water by the control unit. In ground laboratory tests the system exhibited biological stability up to three month. The buffer capacity of the biological filter system is high enough to eliminate the degradation products of about one half of the dead animal biomass as shown in a "crash test". A test series using the laboratory model of the flight hardware demonstrated the biological stability and technical reliability with mission-identical loading and test duration. A comprehensive biological research program is established for the C.E.B.A.S. MINI-MODULE in which five German and three U.S.-American universities as well as the Russian Academy of Sciences are involved.


Asunto(s)
Acuicultura , Sistemas Ecológicos Cerrados , Sistemas de Manutención de la Vida/instrumentación , Vuelo Espacial/instrumentación , Animales , Biomasa , Biomphalaria/crecimiento & desarrollo , Biomphalaria/metabolismo , Ciprinodontiformes/crecimiento & desarrollo , Ciprinodontiformes/metabolismo , Estudios de Evaluación como Asunto , Oxígeno/análisis , Desarrollo de la Planta , Plantas/metabolismo , Agua/análisis
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