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Resumen: Introducción y objetivos: Numerosos estudios han demostrado los beneficios del levosimendán en pacientes con insuficiencia cardiaca crónica y aguda; sin embargo, los resultados son contradictorios cuando se analiza el uso de levosimendán previo a cirugía de revascularización miocárdica y disfunción ventricular severa. El objetivo de este estudio es valorar el rendimiento del precondicionamiento con levosimendán en cirugía de revascularización coronaria en pacientes con disfunción ventricular severa. Métodos: Se realizó un estudio de cohortes retrospectivo emparejado por escala de propensión. Participantes: pacientes intervenidos desde enero de 2009 a octubre de 2019 de cirugía de revascularización coronaria, asociada o no a cirugía mitral de etiología isquémica/funcional con FEVI ≤ a 35%. Se dividieron en dos cohortes, según si recibieron levosimendán (Levo) o no (NoLevo) previamente a la intervención, quedando tras el emparejamiento 64 pacientes por cohorte. Variables analizadas: morbimortalidad postoperatoria, reingreso y mortalidad en el seguimiento. Análisis estadístico: los datos categóricos se compararon mediante χ2 o test de Fisher, y los cuantitativos mediante t de Student o W de Wilcoxon. Se estimó el RR/HR para valorar la asociación entre el uso de levosimendán preoperatorio y las variables resultado. Resultados: El uso de levosimendán preoperatorio no disminuyó la mortalidad (RR = 0,86, p = 0,770), ni la estancia hospitalaria, ni tampoco las complicaciones postoperatorias. La supervivencia libre de reingreso cardiológico, mortalidad en seguimiento por cualquier causa y de causa cardiaca fue similar entre cohortes. Conclusiones: Los resultados obtenidos no apoyan el uso extendido de levosimendán previo a la cirugía de revascularización miocárdica en pacientes con disfunción ventricular severa. Abstract: Introduction and objectives: Numerous studies have demonstrated the benefit of levosimendan in patients with chronic and acute heart failure. However, when it comes to its preoperatory use in coronary by-pass surgery in patients with severe ventricular dysfunction, there are some contradictory results. The objective of this study is assessing preconditioning efficiency with levosimendan in surgical myocardial revascularization in patients with severe ventricular dysfunction. Methods: We design a propensity score-matched cohort study. The study included patients with a LVEF less or equal to 35% who underwent isolated coronary artery by-pass grafting or associated to ischemic/functional mitral surgery from January 2009 to October 2019. They were split into two cohorts whether they received levosimendan preoperatively (Levo) or not (NoLevo); after matching there were 64 patients per cohort. Outcome variables were postoperative morbi-mortality, readmission and follow-up mortality. Statistical analysis: categorical data were compared with a Chi-square or Fisher exact test, and quantitative data with a t-Student or W-Wilcoxon tests. RR/HR were estimated for assessing the association between preoperative use of levosimendan and outcomes. Results: Preoperative levosimendan use did not decreased in-hospital mortality (RR = 0,86, p = 0.770), and neither do hospital stay, nor postoperative complications. Event-free survival was similar between cohorts in terms of cardiological readmissions, all-cause and cardiological follow-up mortality. Conclusions: Our results do not support the widespread use of levosimendan previously to myocardial revascularization surgery in patients with severe ventricular dysfunction.

Introduction Acute arterial embolism is a potential severe complication after cardiac surgery: it can be a clinical manifestation of early prosthetic valve (PV) thrombosis, whose incidence is higher in case of mechanical mitral valve or in presence of subtherapeutic anticoagulation, hemodynamic (atrial fibrillation) or haemostatic (obesity, anaemia, renal failure) predisposing factors (1). EACTA guidelines recommend to start anticoagulation during the first 24 hours after surgery, balancing the haemorragic risk(2). Although, in presence of specific comorbidities and risk factors, life-threatening thrombotic events can complicate postoperative period even following the international recommendations. Methods We report a 73-year-old man, suffering from chronic lymphocytic leukaemia (without treatment) and paroxysmal AF who received mitral mechanical valve replacement with a On-X 27/29 mm valve placed on anti-anatomic position because of a severe mitral insufficiency (with chordal systolic anterior movement) and single coronary artery by-pass graft. Unfractionated heparin (UFH) and acetylsalicylic acid were started 18 hours after surgery, in order to maintain an aPTT ratio of 1.5 to 2.5. On postoperative day (POD) 4 patient presented sudden pain and signs of acute hypoperfusion in left leg (distal femoral artery territory), requiring urgent surgery. Transthoracic echocardiography was performed but limited by artefacts and suboptimal acoustic windows. Considering the high risk surgery and the usefulness of early transoesophageal echocardiography (TOE), the patient received a general anaesthesia with tracheal intubation. Results Successful open embolectomy on the common femoral artery was performed; UFH perfusion was maintained during the whole duration of the procedure without haemorrhagic complication. Intraoperative TEO detected spontaneous echo contrast in left atrial appendage and reduced motion with impaired coaptation of the right leaflet (red arrows in figure); neither valvular-atrial-ventricular thrombus nor increased transvalvular gradient nor regurgitation were found. Postoperative TEO (POD 3) showed a PV with normal leaflets movement, without significative stenosis/regurgitation. Warfarin was started on POD 4 and heparin bridging was discontinued when INR target range was reached. Discussion In patient with multiple thrombotic risk factor (id malignancy, AF) adequate anticoagulation level can be difficult to reach: in these cases, serious thrombotic complications must be highly suspected even when guidelines have been followed. Prompt diagnosis and aggressive treatment are crucial to guarantee a good prognosis. Early TOE and a “tailored” anticoagulation therapy play a fundamental role in the management of such complications.

Primary graft dysfunction after heart transplantation (HTx) has a very high mortality rate, especially if the left ventricle (PGD-LV) is involved. Early diagnosis is important to select the appropriate therapy to improve prognosis. The value of high-sensitivity troponin T (HS-TNT) measurement obtained at patient arrival at the intensive care unit was analyzed in 71 HTx patients. Mild or moderate PGD-LV was defined by hemodynamic compromise with one of the following criteria: left ventricular ejection fraction 15 mm Hg, pulmonary capillary wedge pressure >20 mm Hg, cardiac index 10) or newly placed intra-aortic balloon pump. The mean recipient age was 54 +/- 12 years (73% men), and donor age was 47 +/- 11 years. Ischemic time was 200 +/- 51 minutes, and coronary bypass time was 122 +/- 31 minutes. Nine (13%) HTx patients were diagnosed with PGD-LV post-HTx, 8 with biventricular dysfunction. Four patients died, 2 with PGD-LV (22%) and 2 without PGD (4%). Mean HS-TNT before HTx was 158 +/- 565 ng/L, and post-HT was 1621 +/- 1269 ng/L. The area under the curve (receiver-operator characteristic) of HS-TNT to detect patients at risk of PGD-LV was 0.860 (P < .003). A cutoff value of HS-TNT >2000 ng/L had a sensitivity of 75% and specificity of 87% to identify patients at risk of PGD-LV. Multivariate analysis identified HS-TNT >2000 ng/L (P < .02) and coronary bypass-time (P < .01) as independent predictors of PGD-LV. HS-TNT >2000 ng/L at intensive care admission after HT and prolonged coronary bypass time were the most powerful predictors of PGD-LV. HS-TNT may be helpful for early detection of HTx patients at risk of PGD-LV.

399 La canalizacion de vias venosas centrales en las unidades de reanimacion es un acto rutinario con un 15% de incidencias de complicaciones. El uso de ecografia bidimensional para su cateterizacion tiene un grado de evidencia tipo Ia. Presentamos el caso de un paciente de 73 anos que preciso la cateterizacion de la vena femoral para colocar un sistema de hemodiafiltracion durante el postoperatorio de una sustitucion valvular aortica y revascularizacion coronaria. El acceso venoso habia sido imposible previamente con la tecnica habitual sin utilizar la ecografia. El uso del ecografo (Esaote‚ MyLab 25), con sonda lineal 5-10 MHz, permitio visualizar la situacion posterior de la vena femoral derecha respecto a la arteria, a 2,5 cm de profundidad. La orientacion tangencial de la aguja respecto a la arteria, permitio la puncion venosa y canalizacion de forma habitual mediante la tecnica de Seldinger evitando la puncion arterial accidental.

Resume On presente un modele physique decrivant, apres une reduction accidentelle du debit de sodium dans un reacteur rapide, la fusion, le mouvement et la relocalisation du materiau de gainage du combustible. L’echauffement du combustible est egalement calcule. Ce modele est base sur une approximation monodimensionnelle des equations de Navier-Stokes regissant les ecoulements de la gaine et de la vapeur de sodium. Il tient compte des transferts de masse, de quantite de mouvement et d’energie entre phases. Les hypotheses et les equations generales du modele sont indiquees. Ces dernieres sont resolues par une methode numerique explicite. Une analyse sequentielle des resultats obtenus dans un cas concret ainsi qu'une comparaison avec des resultats experimentaux disponibles sont egalement exposes. La comparaison des resultats des calculs et de l’experience permet de constater que les principaux evenements sont bien decrits.

A precise and reproducible high-performance liquid chromatographic method for the determination of pentylenetetrazol in serum and brain tissue is described. The procedure employs reversed-phase chromatography, monitoring the eluant at 202 nm. Quantification is based on peak-height ratio of the drug to the internal standard (p-methylphenobarbital). A linear response is obtained to 100 micrograms/ml (serum) or micrograms/g (brain tissue). Within-day and between-day precision are smaller than 5%, and analytical recovery is greater than 95%. Numerous drugs tested do not interfere with the assay. The method has been used to investigate the kinetics of pentylenetetrazol distribution in serum and in discrete areas of rat brain.