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La fibrilación auricular (FA) y el aleteo auricular (AA) son las taquicardias más comunes en la aurícula. Afectan al 2% de la población general, y su prevalencia aumenta de forma considerable después de los 60 años. Constituyen dos presentaciones de arritmia de un mismo mecanismo de reentrada. Además de los síntomas a veces incapacitantes (palpitaciones, cansancio, mareos), confieren un mayor riesgo de episodios cardioembólicos y de insuficiencia cardíaca, cuya prevención es esencial. Así, los anticoagulantes se inician si la puntuación CHA2DS2-VASc es alta, y mantener el ritmo sinusal es un objetivo fundamental. Aunque los fármacos se recomiendan como terapia de primera línea, la ablación es mucho más eficaz, sin los efectos nocivos de un antiarrítmico a largo plazo. Por lo tanto, la ablación se considerará al principio del tratamiento: en la práctica, tan pronto como fracase el primer fármaco antiarrítmico. El principio de este procedimiento, que tiene una tasa de riesgo baja, pero cuyo impacto es potencialmente grave, debe discutirse durante una consulta con un especialista en arritmología. La taquicardia auricular focal (TAF) es infrecuente, benigna y afecta a personas jóvenes. Por lo tanto, sólo se tratan las formas sintomáticas o responsables de cardiopatía arrítmica.

Le traitement par ablation, recommandé en première intention après échec du traitement anti-arythmique médicamenteux, nécessite l’utilisation de dispositifs médicaux (DM) très coûteux.

A study on a flat sheet membrane test unit for nanofiltration (NF) and reverse osmosis (RO) with synthetic and natural waters was carried out in order to evaluate the performance of four NF/RO membranes for the removal of selected organic micro-pollutants. The influence of molecular weight and membrane material on removal efficiencies was shown. Perfluorinated compounds and X-ray contrast agents with molecular weights larger than 300 g/mol are rejected to a percentage of more than 90%. Pharmaceuticals and antibiotics show rejection values larger than 60%. For the substances with a molecular weight between 100 and 200 g/mol there is a large range of rejection values depending on the membrane type. RO membranes usually achieve higher rejection values than NF membranes. Rejection also depends on the type of organic micro-pollutant. Although NF/RO membranes do not reject substances selectively, NF/RO is a suitable treatment technology for their removal if this is desired. However, it has to be considered that water composition is changed drastically by NF/RO such that a post treatment of the permeate may be required to keep up with the drinking water standards. For full-scale application also the dosage of antiscalants has to be taken into account. In Germany there is a lively discussion about the discharge of concentrates when authorities have to decide on the realization of NF/RO plants.

Ozonation of the complexing agent ethylenediaminetetra(methylenephosphonic acid) (EDTMP) was studied with bench-scale experiments. As it turned out that EDTMP is totally oxidized within a few seconds, a mechanism for the reaction of EDTMP with ozone is presented which predicts the formation of the herbicide N-phosphonomethylglycine (glyphosate) and its major metabolite aminomethylphosphonic acid (AMPA). The experimental results confirm the predicted mechanism as well as the formation of glyphosate and AMPA during ozonation of waters containing EDTMP.

The main components of organic micro pollution regularly found in the river Elbe, belong to the wide spectrum of pesticides, nitro and chloro benzenes and the chelating agents, especially ethylenediaminetetraacetic acid (EDTA). The level of organic micro pollution with pesticides and the other organic micro pollutants in the upper and middle reaches of the river Elbe between Schmilka and Wittenberge was determined over a period of nearly three years. Four sample preparation methods (SPE: solidphase extraction and LLE: liquid-liquid extraction both with and without derivatization) have been used to analyze a wide spectrum of pesticides with different polarities by GC/ECD, NPD and MS. The pesticide pollution caused by the triazines decreases significantly from 0.35 µg/l (mean value) in 1992 up to 0.15 µg/l (mean value) in 1994. The correlation with the river water flow shows the diffuse character of the triazine input. In the last year of the pesticide screening a change to the more polar substances such as phenoxyalkanoic acid and nitrophenol pesticides as well as chloralkanoic acid pesticides have been noticed. The origin of trichloroacetic acid (TCA) can be explained by the waste influence, supported by the good correlation of the TCA course with the chloroform concentrations determined.

In presence of disinfectants, PAH are remobilized from the coal tar lining of water distribution mains. Reactions of the PAH with chlorine and chlorine dioxide can lead to chlorinated PAH that might show higher mutagenic effects than the parent PAH. The application of the solid-phase microextraction as a sampling preparation method in combination with a gas chromatographic mass spectrometric device is a reliable and useful method to achieve detection limits in the lower nanogramme-per-liter level for PAH and chlorinated PAH. Thus, the reactions of four PAH (anthracene, fluoranthene, fluorene, and phenanthrene) with chlorine and chlorine dioxide under conditions prevalent in drinking water distribution systems could be investigated. In batch experiments with demineralized and drinking water at pH 7, the concentrations of fluoranthene, fluorene, and phenanthrene remained constant, whereas anthracene reacted quantitatively with both disinfectants. In these reactions, no chlorinated products could be detected, only mono-hydroxyanthracene and anthraquinone were formed. A reaction mechanism for both reaction products is proposed. The results suggest that oxidation is the major pathway of the reaction of PAH with disinfectants in the systems under investigation.

An ethanol extract derived from the roots of Eleutherococcus senticosuswas found to influence markedly the cytokine synthesis of activated whole blood cultures of ten healthy volunteers. Whereas the synthesis of Rantes was increased over a wide range of concentrations, the release of IL‐4, IL‐5 and IL‐12 was significantly inhibited. An inhibition at higher concentrations, switching to a stimulation at lower doses of the extract was seen with G‐CSF, IL‐6 and IL‐13. From these particular immuno‐pharmacological effects of Eleutherococcus senticosuswe suggest this herbal preparation possesses immuno‐modulatory potency, rather than just being immuno‐suppressive or ‐stimulating. Copyright © 2001 John Wiley & Sons, Ltd.

An ethanol extract derived from the roots of Eleutherococcus senticosus was found to influence markedly the cytokine synthesis of activated whole blood cultures of ten healthy volunteers. Whereas the synthesis of Rantes was increased over a wide range of concentrations, the release of IL-4, IL-5 and IL-12 was significantly inhibited. An inhibition at higher concentrations, switching to a stimulation at lower doses of the extract was seen with G-CSF, IL-6 and IL-13. From these particular immuno-pharmacological effects of Eleutherococcus senticosus we suggest this herbal preparation possesses immuno-modulatory potency, rather than just being immuno-suppressive or -stimulating. Copyright © 2001 John Wiley & Sons, Ltd.

La principale cause de décès chez l’hémodialysé est la mort subite qui représente 25 % de la mortalité. Dans la population générale, elle est liée dans la grande majorité des cas à une tachyarythmie ou une bradyarythmie. Ces troubles du rythme et de la conduction sont favorisés par les variations électrolytiques et volémiques brutales, l’ischémie myocardique, les myocardiopathies et l’activité sympathique. Or toutes ces conditions sont fréquentes chez les patients insuffisants rénaux chroniques hémodialysés. L’objectif de cette étude est de déterminer les facteurs favorisants les troubles du rythme et de la conduction, notamment ceux liés au traitement par l’hémodialyse, à l’aide d’un holter implantable (ILR, Reveal XT®, Medtronic) permettant la surveillance en continu de ces troubles.