Avaliação dos níveis plasmáticos do peptídeo natriurético NT-proBNP em cães da raça Poodle em diferentes estágios da doença valvar crônica mitral / Evaluation of plasma levels of NT-proBNP natriuretic peptide in Poodle dogs at different stages of chronic mitral valve disease

A doença valvar crônica mitral (DVCM) é comum em cães e pode não causar sintomas clínicos da insuficiência cardíaca (IC) durante anos. O peptídeo natriurético tipo B (BNP) é armazenado nos miócitos ventriculares e secretado para circulação com seu fragmento NT-proBNP, quando ocorre aumento. Este estudo avaliou os níveis plasmáticos do peptídeo natriurético NT-proBNP em cães da raça Poodle em diferentes estágios da DVCM, seguindo as diretrizes do American College of Veterinary Internal Medicine (ACVIM, 2009). Amostras de sangue foram coletadas para determinação do biomarcador NT-proBNP para comparação entre grupos. As medianas do NT-proBNP nos grupos estudados foram: 551pmol/L (controle), 302pmol/L (grupo B1), 1.033pmol/L (grupo B2), 954pmol/L (grupo C) e 5.541pmol/L (grupo D). Mediante o uso de um ponto de corte ideal de >709pmol/L, foi possível identificar os cães com aumento cardíaco verdadeiro daqueles sem aumento cardíaco, com sensibilidade de 75% e especificidade de 100%. O NT-proBNP aumentou de acordo com o avanço dos estágios da DVCM, sendo os estágios B2, C e D aqueles com valores mais elevados desse biomarcador. Para o estágio B2, a mensuração do NT-proBNP mostrou ser uma excelente ferramenta para diagnosticar precocemente o aumento cardíaco em cães da raça Poodle.(AU)

Chronic mitral valve disease (CMVD) is common in dogs, it may not cause clinical symptoms of heart failure (HF) for years. The type B natriuretic peptide (BNP) is stored in the ventricular myocytes and secreted for circulation with its NT-proBNP fragment, when an increase occurs. This study evaluated the plasma levels of the NT-proBNP natriuretic peptide in Poodles at different stages of CMVD, following the guidelines of the American College of Veterinary Internal Medicine (ACVIM, 2009). Blood samples were collected for determination of NT-proBNP biomarker for comparison between groups. This median NT-proBNP in the studied groups were: 551pmol/L (Control), 302pmol/L (Group B1), 1,033pmol/L (Group B2), 954pmol/L (Group C) and 5,541pmol/L (Group D). Using an ideal cutoff of > 709pmol/L it was possible to identify dogs with true heart enlargement of those without a cardiac increase with sensitivity of 75% and specificity of 100%. NT-proBNP increased according to the progress of the stages of CMVD, being that stages B2, C and D, with the highest values of the biomarker. To stage B2, the NT-proBNP measurement proved to be an excellent tool for early diagnosis of cardiac enlargement in Poodles.(AU)

Association of levels of N-terminal-pro-B-type natriuretic peptide with localisation of thrombus in acute pulmonary embolism.

Background and objectives. Brain-natriuretic peptide (BNP) is a potent natriuretic, diuretic hormone that is released from heart into the circulation. We aimed to investigate whether N-terminal-pro-BNP (pro-BNP) could predict localisation of thrombus in patients with acute pulmonary embolism. Methods. Emergency patients found to have thrombosis in the pulmonary artery on helical computed tomography were enrolled. The thrombi which were localised in the main/right or left pulmonary artery were classified as central and those at segmentary/sub-segmentary levels as peripheral. The patients were evaluated by an echocardiogram and pro-BNP levels were measured. Results. Forty-nine patients were enrolled. The thrombus was unilateraly located in 63.3 percent patients and peripherally in 81.6 percent. The difference in pro-BNP levels between those with central and peripheral thrombi was significant (p<0.05). Pro-BNP levels of patients with and without evidence of right ventricular overload (pulmonary hypertension, right heart dilatation, interventricular septal hypokinaesia) were also significantly different (respectively, p<0.001, p<0.01, p<0.01). The pro-BNP levels of patients who were followed up in the intensive care unit and needed thrombolytic treatment were significantly higher (respectively p<0.001, p<0.01). Conclusions. Higher pro-BNP levels indicate higher probability of more central location of thrombus, resulting in a more adverse clinical course. Further studies are needed to determine the predictive values of pro-BNP levels for localisation of pulomnary embolus.