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Summary: Introduction: the amino-terminal pro brain-type natriuretic peptide (NT-proBNP) is a diagnostic and prognostic biomarker in heart failure. Its use as a prognosis predictor of postoperative evolution in cardiac surgery has not been established. Objective: to determine if the value of preoperative NT in cardiac surgery is associated with postoperative evolution parameters. Primary objective: to evaluate its association with the length of stay in intensive care unit. Secondary objectives: to evaluate its association with the time of mechanical ventilation and inotropic agents requirements. To determine the evolution of NT-proBNP concentration after cardiopulmonary bypass. Methods: multicentric retrospective study, endorsed by the Research Committee of the National Institute of Cardiac Surgery and the Ethic Research Committee of the Clinic Hospital. It included patients who underwent cardiac surgery between March and August 2018. NT-proBNP was measured during anesthesia induction and after cardiopulmonary bypass. A possible association of preoperative NT-proBNP with risk factors and type of procedure performed was studied. By analysing the ROC curve, the area under curve (AUC) was calculated and then, the best cut-off value of NT-proBNP to predict prolonged intensive care unit stay was determined. Intensive care unit stays, mechanical ventilation and inotropic requirements were defined as prolonged when they exceeded 2 days, 6 and 24 hours respectively. Through the use of multivaried logistics, the predicting value of NT-proBNP was determined for each one of the aforementioned variables. A value of alfa 0.05 was considered significant. Results: a total of 155 patients were included in the study. Age, creatininemia, and left ventricular ejection fraction were 65.8±11.4 years, 1.15±1.10 mg/dl and 52.8±11.9% respectively. Female prevalence was 30.3%, arterial hypertension 77.4%, diabetes mellitus 25.2% and dyslipidemia 50.3%. In 42.6% isolated myocardial revascularization was performed, in 12.9% myocardial revascularization plus one or more valve procedures, and in 44.5% isolated valve procedures. In all cases there was a significant reduction between preoperative (443 pg/ml, interquartile range 143-1.193) and postoperative NT-proBNP (362 pg/ml, interquartile range 138-939) (p<0.001). Age, creatininemia, left ventricular ejection fraction, functional classification IV of the New York Heart Association and dyslipidemia turned out to be predictors of preoperative NT-proBNP. Preoperative NT-proBNP was higher in patients with prolonged intensive care unit stay, mechanical ventilation and inotropic requirements. However, it turned out to be an independent predictor only for prolonged intensive care unit stay. (OR=1.62; IC95%:1.11-2.35. p=0.012). The best cut-off value for prolonged intensive care unit stay was 409 pg/ml (AUC=0.68). Conclusion: preoperative determination of NT-proBNP is an efficient tool to predict postoperative evolution. Cardiopulmonary bypass is associated to a significant drop in that marker.

Resumo: Introdução: a porção terminal amino do peptído natriurético tipo B é um biomarcador diagnóstico e prognóstico na insuficiência cardíaca. Seu uso como preditor prognóstico no pós-operatório de cirurgia cardíaca não está estabelecido. Objetivo: determinar se o valor de NT-proBNP no período pré-operatório de cirurgia cardíaca está associado a parâmetros de evolução pós-operatória. Objetivo primário: avaliar sua associação com tempo prolongado de internação em unidade de terapia intensiva. Objetivos secundários: associação com tempo de ventilação mecânica e necessidade inotrópica. Determinar a evolução da concentração de NT-proBNP após circulação extracorpórea. Método: estudo multicêntrico retrospectivo endossado pelo Comitê de Pesquisa do Instituto Nacional de Cirurgia Cardíaco e pelo Comitê de Ética da Pesquisa do Hospital da Clínica. Foram incluídos pacientes operados de março a agosto de 2018. O NT-proBNP foi dosado durante a indução anestésica e após a circulação extracorpórea. O NT-proBNP foi comparado de acordo com os fatores de risco e procedimentos realizados. A área da curva (AUC) foi determinada pela análise da curva ROC e o melhor ponto de corte NT-proBNP foi estabelecido na previsão do tempo prolongado de internação em unidade de terapia intensiva. O tempo de internação em unidade de terapia intensiva, tempo de ventilação mecânica e necessidade inotrópica prolongada foram definidos como maiores que 2 dias, 6 e 24 horas, respectivamente. Um alfa de 0,05 foi considerado significativo. Resultados: 155 pacientes foram incluídos. Idade, creatininemia e fração de ejeção do ventrículo esquerdo foram 65,8± 11,4 anos, 1,15 ± 1,10 mg/dl e 52,8 ± 11,9 %, respectivamente. A prevalência do sexo feminino foi 30,3%, hipertensão arterial 77,4%, diabetes mellitus 25,2% e dislipidemia 50,3%. Em 42,6%, foi realizada revascularização do miocárdio isolada, em 12,9% revascularização do miocárdio associada a um ou mais procedimentos valvares, e em 44,5% procedimentos puros da válvula. Em todos os casos, houve uma diminuição significativa entre o pré-operatório (443 pg/ml, rango interquartílico 143-1.193) e o pós-operatório de NT-proBNP (362 pg/ml, rango interquartilico 138-939) (p <0,001). Idade, cretininemia, fração de ejeção do ventrículo esquerdo, classe funcional IV da New York Heart Association e dislipidemia foram preditores de NT-proBNP pré-operatório. NT-proBNP pré-operatório foi elevado em pacientes com tempo prolongado de internação em unidade de terapia intensiva, tempo de ventilação mecânica e necessidade inotrópica prolongada, mas apenas acabou por ser preditor independente em internação prolongada em unidade de terapia intensiva (OR=1,62; IC95%:1,11-2,35. p=0,012). O melhor valor de corte para internação prolongada foi de 409 pg/ml (AUC = 0,68). Conclusão: a determinação pré-operatória de NT-proBNP é útil como ferramenta na previsão da evolução pós-operatória. A circulação extracorpórea está associada a uma diminuição significativa desse marcador.

Resumen: El siguiente artículo reporta el caso clínico de una paciente portadora de trombosis valvular bioprotésica en posición aórtica. La trombosis sobre válvula bioprotésica es una patología de baja prevalencia pero que puede conducir a un aumento en la tasa de accidentes cerebrovasculares, así como a largo plazo ser un factor coadyuvante de degeneración bioprotésica. Actualmente, el diagnóstico de la misma se realiza mediante ecocardiografía por el hallazgo de un incremento del gradiente medio transvalvular mayor a 50%, engrosamiento de los velos o movimiento anormal de los mismos, con una especificidad de 93%. El tratamiento con warfarina mostró ser efectivo en 83% de los pacientes, según un estudio prospectivo, así como en el caso de nuestra paciente que luego del tratamiento presenta una clara mejoría sintomática con disminución de los gradientes transvalvulares.

Summary: The following article reports a clinical case of a patient with bioprosthetic valvular thrombosis in aortic position. Bioprothesis valve thrombosis is a pathology of low prevalence but it can result in an increase in the rate of stroke as well as in the long term, a factor promoting bioprosthetic degeneration. Currently the diagnosis of the bioprothesis valve thrombosis is made by echocardiography by the finding of an increase in the mean transvalvular gradient greater than 50%, thickening of the cups and / or an abnormal movement of them with a specificity of 93%. Treatment with warfarin has shown to be effective in 83% of patients according to a prospective study, as well as in the case of our patient, with a clear symptomatic improvement as well as a decrease in mean transvalvular gradient after treatment.

Resumen: Introducción y objetivos: existe tendencia a procurar un aumento de los beneficios de la cirugía de revascularización mediante el uso de ambas arterias mamarias internas (DAMI). Nuestro objetivo fue analizar los resultados nacionales a largo plazo del uso de DAMI en una población de pacientes con ángor estable con indicación de revascularización aislada. Métodos: se recabaron los datos de pacientes operados desde 2006 a 2015 en Uruguay. Se extrajeron variables demográficas, operatorias y de seguimiento. Evaluamos mortalidad operatoria, mediastinitis y sobrevida. Estratificamos la población por edad en menor o mayor o igual a 65 años. Para disminuir la heterogeneidad entre grupos realizamos comparación mediante puntaje de propensión (PS) en menores de 65 años. Resultados: se incluyeron 2.791 pacientes. Los pacientes con DAMI eran más jóvenes (57,3?8,5 vs 65,9?8,6 años, p=0,001), con menor porcentaje de sexo femenino (15,6% vs 28,2%, p=0,001), menor incidencia de hipertensión (74,1% vs 79,8%, p=0,012) y menor Euroscore (1,35 vs 4,23, p=0,001). En ³65 años, DAMI resultó ser predictor independiente de mortalidad operatoria y peor sobrevida. En ?λτ;65 años pareados por PS, los pacientes con DAMI tuvieron mayor sobrevida, pero DAMI no fue predictor independiente para la misma. La revascularización completa en pacientes con una mamaria igualó la sobrevida a DAMI. La incidencia de mediastinitis fue similar en ambos grupos en todos los casos. Conclusiones: el uso de DAMI resultó perjudicial en pacientes 65 años. Dicha técnica ofrece mejores resultados en pacientes menores de 65 años, aunque su beneficio como predictor independiente parecería estar confundido por otras variables como la edad y la revascularización completa.

Summary: Introduction and objectives: there is a tendency to increase the benefits of surgery in coronary artery disease using both internal mammary arteries (BIMA). Our objective was to evaluate our long term national results in patients with stable coronary artery disease who receive isolated coronary artery bypass grafts (CABG) using BIMA. Methods: patients operated between 2006 and 2015 were included. Patients’ demographic, operative and postoperative variables were extracted. The outcomes were operative mortality, deep sternal infection and survival. Our population was stratified by age in ?λτ; and ³ 65 years old. In order to decreased group heterogeneity, propensity match (PM) was performed. Results: 2.791 patients were included. Patients with BIMA were younger (57.3?8,5 vs 65,9?8,6 years old, p=0,001), lower incidence of females (15,6% vs 28,2%, p=0,001), of hypertension (74,1% vs 79,8%, p=0,012) and lower Euroscore (1,35 vs 4,23, p=0,001). In patients ³ 65 years old, BIMA was an independent predictor for worse operative mortality and survival. In PM patients ?λτ; 65 years old, BIMA was associated with improved survival but failed to be an independent predictor for it. Patients who received single internal mammary artery and had complete revascularization had similar survival to BIMA patients. Deep sternal infection was similar between groups in both strata. Conclusions: the use of BIMA was found to be an independent predictor for worse outcomes in patients ³ 65 years old. BIMA has better results for patients ?λτ; 65 years old although its independent benefit is confused by other variables such as age and complete revascularization.

Abstract Objective: On pump beating/non-beating coronary artery bypass grafts (CABG) has been compared in patients with unstable angina and/or severe left ventricular dysfunction. There is scarce evidence regarding the beneficial use of on-pump beating CABG in patients with stable angina and normal left ventricular function. Our aim was to study the postoperative results using both techniques in this group of patients. Methods: One thousand one hundred and forty-five patients with stable angina underwent on-pump isolated CABG in Uruguay from 2011 to 2015. Patients were grouped into beating/non-beating CABG. Operative mortality and long-term survival were evaluated as primary outcome. Logistic regression analysis was performed to define the predictive role of aortic cross clamp (AXC) on prolonged inotropic support, ventilator support and intraoperative glycemia. Results: Among the included patients, 988 underwent aortic cross clamp. No differences were found in operative mortality, stroke and long-term survival among both groups. Patients without AXC showed higher intraoperative values of glycemia and higher incidence of postoperative prolonged mechanical ventilator support (7.6% vs. 2.4%; P=0.001). The need for prolonged inotropic support was lower in this group of patients (27.4% vs. 49.5%; P<0.001). Conclusion: On-pump beating CABG has similar operative mortality and long-term survival compared with conventional AXC. Higher intraoperative glycemia and higher incidence for prolonged mechanical ventilator is associated with on-pump beating CABG. On the contrary, higher incidence for prolonged inotropic support is associated with AXC. Taking these factors into consideration, both techniques are safe and allow the surgeon to choose the most comfortable option.

Setenta y ocho pacientes consecutivos (media de 63±10 años, 79,5% hombres) con antecedentes de infarto de miocardio e indicación de cirugía de by-pass coronario (CBC), fueron estudiados con ecodobutamina a bajas dosis antes (ED1) y a los tres meses de seguimiento (ED2), para evaluar su utilidad clínica en la detección de viabilidad miocárdica. Determinamos la utilidad clínica esperada global para pacientes (P; n=67) y para los territorios coronarios disinérgicos revascularizados (T; n=126) usando la estrategia clásica: resultados de ED1 con los resultados del ecocardiograma basal de seguimiento (EB2) y aplicándoles una estrategia complementaria que sometía los falsos positivos (FP) y falsos negativos (FN) a los resultados de ED2. Las utilidades asignadas en cada nodo del árbol de decisión fueron máxima (1,0), submáxima (0,75) e intermedia (0,50), usando el método del repliegue como modelo matemático para la estrategia clásica. Para la complementaria: 0,89, 0,75 y 0,50, respectivamente. Resultados: las utilidades esperadas para P y T, cuando se realizó ED1 fueron 0,84 y 0,89 para el diagnóstico de viabilidad, 0,85 y 0,82 para confirmarla y 0,83 y 0,82 para no confirmarla en EB2, respectivamente. Las utilidades esperadas cuando se realiza ED2 para P y T fueron en FP 0,74 y 0,76 y en FN 0,47 y 0,45, respectivamente. Conclusiones: los resultados de la ecodobutamina a bajas dosis son de gran utilidad clínica para la pesquisa de músculo viable o cicatrizal antes de la CBC, así como también cuando se encuentran resultados discordantes en el seguimiento, especialmente con los FP.

Seventy-eight consecutive patients (mean 63±10 years, 79,5% men) with a story of myocardial infarction and indication of coronary by-pass surgery (CBC) were studied with low-dose dobutamine echocardiography before (ED1) and and at three months follow-up (ED2) to evaluate its clinical utility in the detection of viable myocardium. We determined the expected utilities of global patients (P n=67) and coronary territories (T n= 126) with the classic strategy: ED1 and results of the rest follow-up echocardiogram (EB2) and applying to it a complementary strategy which submitted false positives (FP) and false negatives (FN) to ED2 results. Assigned utilities in each node of the decision tree are: maximal (1,0), sub-maximal (0,75) and intermedium (0,50) using the folding method as mathematical model. Results: global P and T expected utilitities with the decision of performing an ED1 are 0,84 and 0,89 respectively for viability detection, 0,85 and 0,82 to confirm it and 0,83 and 0,82 to not confirm it respectively in EB2. The expected utilities with the decision of performing an ED2 to FP are 0,74 and 0,76 (viability was detected in 66% of P and in 58% of T) and 0,47 and 0,45 respectively, applied to FN. Conclusions: low-dose dobutamine echocardiography brings high clinical utility in finding viable or scar myocardium before CBC, and when discordant results are found in follow-up, in particular with FP.