Perfusão da artéria pulmonar não melhora os índices de fator natriurético cerebral (BNP) em estudo experimental em suínos / Pulmonary artery perfusion does not improve brain natriuretic peptide (BNP) levels in suine experimental research

OBJETIVO: Avaliar se perfusão controlada do tronco pulmonar durante circulação extracorpórea (CEC) modifica os níveis de BNP expressos pelo miocárdio ventricular. MÉTODOS: Estudo experimental com 32 porcos, divididos em dois grupos de acordo com estratégia de CEC - grupo I (cardioplegia) e grupo II (coração batendo). Ambos os grupos foram alocados em três subgrupos, de acordo com a estratégia de perfusão pulmonar - subgrupo A (controle: sem perfusão pulmonar), subgrupo B (perfusão pulmonar com sangue arterial) e subgrupo C (perfusão com sangue venoso). Nos subgrupos B e C, pulmões foram perfundidos por 30 minutos, utilizando pressão arterial média pulmonar (PAPM) préoperatória como pressão de perfusão, a qual foi controlada com manômetro. PAPM e resistência vascular pulmonar (RVP) foram medidas após saída de CEC com cateter de Swan-Ganz. No período pré-operatório e após 30 minutos de perfusão pulmonar, fragmentos de miocárdio ventricular direito foram coletados para avaliar expressão de peptídeo natriurético cerebral (BNP) e padrão histológico tecidual. Técnicas de imunohistoquímica e hematoxilina-eosina foram utilizadas para determinar, respectivamente, expressão de BNP e lesões inflamatórias miocárdicas. RESULTADOS: Nos animais submetidos à perfusão controlada do tronco pulmonar, houve redução pós-operatória da PAPM (P=0,03) e da RVP (P=0,005). Não houve diferenças entre os subgrupos do grupo I (P=0,228) e subgrupos do grupo II (P=0,325) quanto à expressão pós-operatória de BNP. Não houve diferenças entre subgrupos com e sem perfusão pulmonar quanto à intensidade das lesões inflamatórias miocárdicas identificadas no pós-operatório (P>0,05). CONCLUSÃO: Perfusão controlada do tronco pulmonar por 30 minutos não foi suficiente para promover alterações substanciais na expressão de BNP e no padrão histológico miocárdico do ventrículo direito.

OBJECTIVE: Assess if the main pulmonary artery controlled perfusion over cardiopulmonary bypass (CPB) modifies BNP levels expressed by the ventricular myocardium. METHODS: Experimental research involving 32 pigs, divided into two groups according to CPB strategy - group I (cardioplegia) and group II (beating heart). Both groups were allocated into three subgroups according to lung perfusion strategy - subgroup A (control: no lung perfusion), subgroup B (lung perfusion with arterial blood) and subgroup C (lung perfusion with venous blood). In subgroups B and C, lung was perfused for 30 minutes, using preoperative mean pulmonary artery pressure (MPAP) as perfusion pressure, which was monitored through manometer. MPAP and pulmonary vascular resistance (PVR) were measured after coming off CPB using Swan-Ganz catheter. At preoperative time and 30 minutes after lung perfusion, specimens were taken from the right ventricular myocardium aiming to assess brain natriuretic peptide (BNP) and histologic pattern. Immunohistochemical and hematoxylin-eosin techniques were used to determine, respectively, BNP expression and inflammatory myocardial lesions. RESULTS: In animals submitted to controlled lung perfusion, there was a postoperative reduction of MPAP (P=0.03) and PVR (P=0.005).There was no differences among subgroups within the group, I (P=0.228) and subgroups within group II (P=0.325) as to postoperative BNP expression. There were no differences among subgroups with and without lung perfusion as to postoperative inflammatory lesions (P>0.05). CONCLUSION: Main pulmonary artery controlled perfusion for 30 minutes did not yield substantial modifications in BNP expression and histologic pattern of the right ventricular myocardium.

Pulmonary artery perfusion does not improve brain natriuretic peptide (BNP) levels in suine experimental research.

OBJECTIVE: Assess if the main pulmonary artery controlled perfusion over cardiopulmonary bypass (CPB) modifies BNP levels expressed by the ventricular myocardium. METHODS: Experimental research involving 32 pigs, divided into two groups according to CPB strategy--group I (cardioplegia) and group II (beating heart). Both groups were allocated into three subgroups according to lung perfusion strategy--subgroup A (control: no lung perfusion), subgroup B (lung perfusion with arterial blood) and subgroup C (lung perfusion with venous blood). In subgroups B and C, lung was perfused for 30 minutes, using preoperative mean pulmonary artery pressure (MPAP) as perfusion pressure, which was monitored through manometer. MPAP and pulmonary vascular resistance (PVR) were measured after coming off CPB using Swan-Ganz catheter. At preoperative time and 30 minutes after lung perfusion, specimens were taken from the right ventricular myocardium aiming to assess brain natriuretic peptide (BNP) and histologic pattern. Immunohistochemical and hematoxylin-eosin techniques were used to determine, respectively, BNP expression and inflammatory myocardial lesions. RESULTS: In animals submitted to controlled lung perfusion, there was a postoperative reduction of MPAP (P = 0.03) and PVR (P = 0.005).There was no differences among subgroups within the group, I (P = 0.228) and subgroups within group II (P = 0.325) as to postoperative BNP expression. There were no differences among subgroups with and without lung perfusion as to postoperative inflammatory lesions (P > 0.05). CONCLUSION: Main pulmonary artery controlled perfusion for 30 minutes did not yield substantial modifications in BNP expression and histologic pattern of the right ventricular myocardium.

Juvenile dermatomyositis (JDM) and severe pulmonary involvement: case report / Dermatomiosite juvenil (DMJ) e comprometimento pulmonar grave: relato de caso

A dermatomiosite juvenil (DMJ) é uma doença inflamatória não supurativa dos músculos esqueléticos e da pele.Outros órgãos podem estar envolvidos, como, por exemplo, os pulmões. As complicações pulmonares estão associadas a altas taxas de morbimortalidade e podem ocorrer na fase aguda da doença. Devido à raridade, dificuldade no diagnóstico e gravidade do acometimento pulmonar, relatamos o caso de uma menina de 3 anos com DMJ e envolvimento pulmonar que evoluiu para óbito.

Juvenile dermatomyositis (JDM) is an inflammatory, non-pustular disorder of skeletal muscles and skin. Other organs, such as the lungs, can be involved. Pulmonary complications are associated with high morbimortality rates and can develop in the acute phase of the disease. Due to its rarity, diagnosis difficulty and severity pulmonary involvement, we report the case of a 3-year-old girl with JDM and pulmonary involvement and evolution to death.

Microscopic and ultrastructural evaluation of the saphenous vein endothelium for CABG prepared by the no touch technique.

OBJECTIVE: Saphenous vein grafts (SV) used in coronary artery bypass grafting have a limited life and vein occlusion may be the final adverse effect. Efforts to develop new techniques to harvest the saphenous vein may improve the viability of the graft. METHODS: Twenty patients were randomly divided into two groups with the objective of evaluating the vascular endothelium. The No Touch (NT) technique consists in removing the saphenous vein with perivascular tissue. The conventional technique consists in harvesting with "in situ" removal of the perivascular tissue. The standard saphenous vein harvesting procedure used bridged incisions. Characteristics of the vein were considered. Evaluation of the endothelium was achieved by electron microscopy and histologic analysis using hematoxylin eosin staining. The Picrosirius and Masson Trichrome methods were used to analyze subendothelial collagen. RESULTS: Electron microscopy demonstrated that the NT Group had larger non-denudated endothelial areas as well as a smaller number of degraded cells. Histological analysis showed the form and integrity of the saphenous vein layers. A larger amount of collagen fibers were identified in the NT Group. CONCLUSIONS: The NT technique better preserves the saphenous vein endothelium suggesting a more viable graft in the long term.

Avaliação microscópica e ultra-estrutural do endotélio de veia safena preparada pela técnica "no touch" / Microscopic and ultrastructural evaluation of the saphenous vein endothelium for CABG prepared by the no touch technique

OBJETIVO: O enxerto de veia safena (VS) utilizado em revascularização miocárdica possui uma vida útil, sendo o estágio final a oclusão do vaso. Esforços em adquirir novas técnicas de coleta da VS podem possibilitar uma viabilidade maior do enxerto. MÉTODOS: Vinte pacientes foram randomizados e divididos em dois grupos com o objetivo de avaliação do endotélio vascular. A técnica "no touch" (NT) consiste em retirar o segmento de VS com o tecido perivascular. A técnica convencional consiste em retirar a VS, com remoção "in situ" do tecido perivascular e conseqüente vasoespasmo. Houve um padrão de retirada das VS com incisões longitudinais escalonadas. Características da VS foram consideradas. A avaliação do endotélio das VS foi realizada usando microscópio eletrônico (ME) pelo método de varredura e de transmissão. Cortes histológicos das VS foram corados em Hematoxilina-Eosina (HE). O colágeno subendotelial foi analisado pelos métodos de Picro-Sirius e Tricrômio de Masson. RESULTADOS: A ME evidenciou que o Grupo NT possui maiores áreas endoteliais não desnudadas, além de um menor número de células degradadas. A coloração em HE nos permitiu verificar a forma e a integridade das camadas das VS. Há um predomínio maior de fibras colágenas coradas no Grupo NT. CONCLUSÕES: A técnica NT permite uma melhor preservação endotelial da VS, sugerindo um enxerto mais viável em longo prazo.

OBJECTIVE: Saphenous vein grafts (SV) used in coronary artery bypass grafting have a limited life and vein occlusion may be the final adverse effect. Efforts to develop new techniques to harvest the saphenous vein may improve the viability of the graft. METHODS: Twenty patients were randomly divided into two groups with the objective of evaluating the vascular endothelium. The No Touch (NT) technique consists in removing the saphenous vein with perivascular tissue. The conventional technique consists in harvesting with "in situ" removal of the perivascular tissue. The standard saphenous vein harvesting procedure used bridged incisions. Characteristics of the vein were considered. Evaluation of the endothelium was achieved by electron microscopy and histologic analysis using hematoxylin eosin staining. The Picrosirius and Masson Trichrome methods were used to analyze subendothelial collagen. RESULTS: Electron microscopy demonstrated that the NT Group had larger non-denudated endothelial areas as well as a smaller number of degraded cells. Histological analysis showed the form and integrity of the saphenous vein layers. A larger amount of collagen fibers were identified in the NT Group. CONCLUSIONS: The NT technique better preserves the saphenous vein endothelium suggesting a more viable graft in the long term.