Head-to-head comparison of dipyridamole, dobutamine and pacing stress echocardiography for the detection of myocardial ischemia in an animal model of coronary artery stenosis

To compare the sensitivity of dipyridamole, dobutamine and pacing stress echocardiography for the detection of myocardial ischemia we produced a physiologically significant stenosis in the left circumflex artery of 14 open-chest dogs (range: 50 to 89 percent reduction in luminal diameter). In each study, dobutamine (5 to 40 æg kg-1 min-1 in 3-min stages) and pacing (20 bpm increments, each 2 min, up to 260 bpm) were performed randomly, and then followed by dipyridamole (up to 0.84 mg/kg over 10 min). The positivity of stress echocardiography tests was quantitatively determined by a significant (P<0.05) reduction of or failure to increase absolute and percent systolic wall thickening in the stenotic artery supplied wall, as compared to the opposite wall (areas related to the left anterior descending artery). Systolic and diastolic frozen images were analyzed off-line by two blinded observers in the control and stress conditions. The results showed that 1) the sensitivity of dobutamine, dipyridamole and pacing stress tests was 57, 57 and 36 percent, respectively; 2) in animals with positive tests, the mean percent change of wall thickening in left ventricular ischemic segments was larger in the pacing (-19 Ý 11 percent) and dipyridamole (-18 Ý 16 percent) tests as compared to dobutamine (-9 Ý 6 percent) (P = 0.05), but a similar mean reduction of wall thickening was observed when this variable was normalized to a control left ventricular segment (area related to the left anterior descending artery) (pacing: -16 Ý 7 percent; dipyridamole: -25 Ý 16 percent; dobutamine: -26 Ý 10 percent; not significant), and 3) a significant correlation was observed between magnitude of coronary stenosis and left ventricular segmental dysfunction induced by ischemia in dogs submitted to positive stress tests. We conclude that the dobutamine and dipyridamole stress tests showed identical sensitivities for the detection of myocardial ischemia in this one-vessel disease animal model with a wide range of left circumflex artery stenosis. The pacing stress test was less sensitive, but the difference was not statistically significant. The magnitude of segmental left ventricular dysfunction induced by ischemia was similar in all stress tests evaluated

Immunophenotype of normal and leukemic bone marrow B-precursors in a Brazilian population. A comparative analysis by quantitative fluorescence cytometry

The distinction between normal and leukemic bone marrow (BM) B-precursors is essential for the diagnosis and treatment monitoring of acute lymphoblastic leukemia (ALL). In order to evaluate the potential use of quantitative fluorescence cytometry (QFC) for this distinction, we studied 21 normal individuals and 40 patients with CD10+ ALL. We characterized the age-related changes of the CD10, CD19, TdT, CD34 and CD79a densities in normal and leukemic BM. Compared to normal adults, the B-precursors from normal children expressed significantly lower values of CD34-specific antibody binding capacity (SABC) (median value of 86.6 vs 160.2 arbitrary units (a.u.) in children and adults, respectively). No significant age-related difference was observed in the expression of the other markers in the normal BM, or in any of the markers in the leukemic BM. Based on the literature, we set the cut-off value for the normal CD10 expression at 45 x 10Ý a.u. for both age groups. For the remaining markers we established the cut-off values based on the minimum-maximum values in the normal BM in each age group. The expression of CD10 was higher than the cut-off in 30 ALL cases and in 18 of them there was a concomitant aberrant expression of other markers. In 9 of the 10 CD10+ ALL with normal CD10 SABC values, the expression of at least one other marker was aberrant. In conclusion, the distinction between normal and leukemic cells by QFC was possible in 38/40 CD10+ ALL cases

Síndrome do intestino curto: aspectos fisiopatológicos, clínicos e suporte nutricional de longa duraçäo / Short bowel syndrome: physiopathological and clinical aspects, and long-term nutritional support

Os pacientes com Síndrome do Intestino Curto (SIC) necessitam de suporte nutricional parenteral, sem o que a taxa de mortalidade é superior a 80 por cento. A unidade Metabólica do Hospital de Clínicas da Faculdade de Medicina de Ribeirao Preto mantém programa de suporte nutricional parenteral em regime ambulatorial para o paciente com SIC, estabelecido de acordo com a necessidade individual de cada paciente, o que é determinado pela avaliaçao periódica do estado nutricional por meio de critérios clínicos, dietéticos, antropométricos e bioquímicos. Este artigo discute os aspectos fisiopatológicos e clínicos da SIC, bem como a conduta do suporte nutricional de longa duraçao empregada nos pacientes tratados na Unidade Metabólica do Hospital de Clínicas da Faculdade de Medicina de Ribeirao Preto.

Protese traqueal - estudo experimental em caes. / Tracheal prosthesis experimental study in dogs

Este trabalho destinou-se a estudar um novo substituto traqueal. Usando uma placa proteica de poliester (Rhodergon), revestida por silicone em uma de suas faces, a protese traqueal era moldada em cilindros de acrilico de tamanhos diferentes. Foram feitas nao colapsaveis atraves de aneis metalicos incompletos, aplicados a sua face externa e protegidos por uma fina camada de silicone. Onze caes mesticos tiveram um segmento de sua traqueia cervical (de tres a cinco aneis cartilaginosos) substituidos por uma dessas proteses. As anastomoses foram realizadas usando-se fios de sutura monifilamentares (polipropileno prolene 5-0) em tecnicas diferentes. Os resultados foram avaliados atraves de observacoes clinicas, radiograficas, endoscopicas. Finalmente todos os animais foram para autopsia. A protese traqueal mostrou-se satisfatoria como um conduto aereo nao colapsavel mas os resultados obtidos foram insatisfatorios em virtude da ocorrencia de infeccao, deiscencia e estenose

Correlações entre a medida intra-operatória da área útil valvar com parâmetros clínicos e hemodinâmicos em pacientes portadores de estenose mitral / Correlation of intraoperative measurement of valvar useful area with clinical and hemodynamic parameters in patients with mitral stenosis

No presente trabalho, estudou-se a area util valvar mitral,medida intraoperatoriamente pelo metodo proposto por Sader(1975) e sua correlacao com parametros clinicos e hemodinamicos de pacientes portadores de estenose mitral. Obteve-se correlacao significante entre a area valvar mitral e o grau funcional de acordo com New York Heart Association. Obtiveram-se tambem correlacoes significantes (p < 0,05) entre a area valvar mitral, indice cardiaco,fluxo atraves da valva mitral, resistencia vascular sistemica, resistencia arteriolar sistemica, resistencia pulmonar estabelecida pela valva estenotica e resistencia vascular pulmonar. Nao se obtiveram correlacoes significantes (p < 0,05) com a pressao capilar pulmonar, gradiente atraves da valva mitral, resistencia arteriolar pulmonar, trabalho do ventriculo direito e trabalho do ventriculo esquerdo

Estudo do fluxo sanguineo periferico medico pela pletismografia de oclusao venosa em pacientes portadores de estenose mitral. / Peripheral blood flow measured by plethysmography of venous occlusion in patients with mitral stenosis

Realizaram-se medidas do fluxo sanguineo periferico do pe, por plestimografia de oclusao venosa em 11 pacientes portadores de estenose mitral, submetidos a cateterismo cardiaco, e a medida da area util da valva mitral durante intervencao cirurgica Os valores foram baixos na maioria dos pacientes e a correlacao entre o fluxo sanguineo periferico e a area util da valva mitral bem como o indice cardiaco, volume sistolico e resistencia arteriolar sistemica nao foram extatisticamente significantes.Concluem que os achados nao sugerem que o fluxo sanguineo periferico dependa do grau de estenose da valva.Diante do volume de informacoes que contestam a participacao universal do sistema nervoso autonomo simpatico os autores invocam a autorregulacao local para explicar as respostas da circulacao periferica nos portadores de estenose mitral

Estudo da funcao pulmonar em pacientes portadores de estenose mitral. / Pulmonary function in patients with mitral stenosis

Os autores apresentam os resultados de estudos da funcao pulmonar em 20 pacientes submetidos a espirometria e gasometria arterial no pre-operatorio da cirurgia cardiaca para correcao da estenose mitral. Procedeu-se a medida intraoperatoria da area util valvar mitral cujos valores nao apresentaram nenhuma correlacao significante com os diversos parametros da funcao pulmonar

Endocardite em protese de dura-mater provocada pelo Acremonium kiliense. / Endocarditis in prosthesis of dura mater caused by Acremonium kiliense

Os autores registram caso de endocardite em protese de dura-mater, com evolucao desfavoravel, seguida de embolia com abscesso froto-parietal, a direita. Acremonium kiliense GRUTZ, 1925 foi isolado em cultura pura, das duas lesoes. O exame histopatologico revelou a presenca de filamentos micelianos septados, formando massas compactas, diferentes dos encontrados em casos de aspergilose, candidiase e zigomicose. Nao existiam sinais clinicos de qualquer comprometimento do sistema imunologico do paciente