Radionuclide esophageal transit scintigraphy in chronic indeterminate and cardiac forms of Chagas disease.

OBJECTIVES: This study was designed to investigate digestive and heart associations, using esophageal transit scintigraphy in three different groups: patients exclusively with the dilated cardiac form of Chagas disease (DCCh), an indeterminate form of Chagas disease, and healthy controls. As a hypothesis, we assumed that autonomic chagasic denervation is a global process. MATERIALS AND METHODS: Twenty healthy controls and 75 outpatients with Chagas disease, divided into indeterminate form (n = 33) and (DCCh, n = 42), underwent esophageal scitigraphy. The esophageal transit time (ETT) and percentage of esophageal emptying (%EE) were analyzed by group and correlated with left ventricular ejection fraction (LVEF). RESULTS: ETT alterations were found in 57% of indeterminate form and 80% of DCCh. The observed values of ETT and %EE in Chagas disease groups were significantly different from the controls (P-value <0.001). The lowest median ETT was observed for the controls (median = 8.0), followed by indeterminate form (median = 16.5) and DCCh (median = 60.0). Regarding %EE, a higher median value was observed for the controls (median = 92.3), followed by indeterminate form (median = 86.7) and DCCh (median = 56.9). In the DCCh group, ETT and %EE were significantly correlated with LVEF values (r = 0.398; P = 0.015) and (r = 0.475; P = 0.003), respectively. CONCLUSION: An association between left ventricular systolic dysfunction and functional esophageal alterations was observed which was interpreted as indirect evidence of concomitance of gastrointestinal and cardiac disorders. We also found that the greater the impairment of the esophagus's autonomic function, the worse the cardiac dysfunction.

Sympathetic Dysautonomia in Heart Failure by 123I-MIBG: comparison between Chagasic, non-Chagasic and heart transplant patients.

BACKGROUND: Heart failure (HF) is a severe public health problem because of its high morbidity and mortality and elevated costs, thus requiring better understanding of its course. In its complex and multifactorial pathogenesis, sympathetic hyperactivity plays a relevant role. Considering that sympathetic dysfunction is already present in the initial phases of chronic Chagas cardiomyopathy (CCC) and frequently associated with a worse prognosis, we assumed it could be more severe in CCC than in cardiomyopathies of other etiologies (non-CCC). OBJECTIVES: To assess the cardiac sympathetic dysfunction 123I-MIBG) of HF, comparing individuals with CCC to those with non-CCC, using heart transplant (HT) patients as denervated heart parameters. METHODS: We assessed 76 patients with functional class II-VI HF, being 25 CCC (17 men), 25 non-CCC (14 men) and 26 HT (20 men), by use of cardiac 123I-metaiodobenzylguanidine 123I-MIBG) scintigraphy, estimating the early and late heart-to-mediastinum ratio (HMR) of 123I-MIBG uptake and cardiac washout (WO%). The 5% significance level was adopted in the statistical analysis. RESULTS: The early and late HMR values were 1.73 ± 0.24 and 1.58 ± 0.27, respectively, in CCC, and 1.62 ± 0.21 and 1.44 ± 0.16 in non-CCC (p = NS), being, however, higher in HT patients (p < 0.001). The WO% values were 41.65 ± 21.4 (CCC), 47.37 ± 14.19% (non-CCC) and 43.29 ± 23.02 (HT), p = 0.057. The late HMR values showed a positive weak correlation with left ventricular ejection fraction (LVEF) in CCC and non-CCC (r = 0.42 and p = 0.045; and r = 0.49 and p = 0.015, respectively). CONCLUSION: Sympathetic hyperactivity 123I-MIBG) was evidenced in patients with class II-IV HF, LVEF < 45%, independently of the HF etiology, as compared to HT patients.

Sympathetic Dysautonomia in Heart Failure by 123I-MIBG: comparison between Chagasic, non-Chagasic and heart transplant patients / Disautonomia Simpática na Insuficiência Cardíaca pela 123I-MIBG: Comparação entre Pacientes Chagásicos, não-Chagásicos e Transplantados Cardíacos

Abstract Background: Heart failure (HF) is a severe public health problem because of its high morbidity and mortality and elevated costs, thus requiring better understanding of its course. In its complex and multifactorial pathogenesis, sympathetic hyperactivity plays a relevant role. Considering that sympathetic dysfunction is already present in the initial phases of chronic Chagas cardiomyopathy (CCC) and frequently associated with a worse prognosis, we assumed it could be more severe in CCC than in cardiomyopathies of other etiologies (non-CCC). Objectives: To assess the cardiac sympathetic dysfunction 123I-MIBG) of HF, comparing individuals with CCC to those with non-CCC, using heart transplant (HT) patients as denervated heart parameters. Methods: We assessed 76 patients with functional class II-VI HF, being 25 CCC (17 men), 25 non-CCC (14 men) and 26 HT (20 men), by use of cardiac 123I-metaiodobenzylguanidine 123I-MIBG) scintigraphy, estimating the early and late heart-to-mediastinum ratio (HMR) of 123I-MIBG uptake and cardiac washout (WO%). The 5% significance level was adopted in the statistical analysis. Results: The early and late HMR values were 1.73 ± 0.24 and 1.58 ± 0.27, respectively, in CCC, and 1.62 ± 0.21 and 1.44 ± 0.16 in non-CCC (p = NS), being, however, higher in HT patients (p < 0.001). The WO% values were 41.65 ± 21.4 (CCC), 47.37 ± 14.19% (non-CCC) and 43.29 ± 23.02 (HT), p = 0.057. The late HMR values showed a positive weak correlation with left ventricular ejection fraction (LVEF) in CCC and non-CCC (r = 0.42 and p = 0.045; and r = 0.49 and p = 0.015, respectively). Conclusion: Sympathetic hyperactivity 123I-MIBG) was evidenced in patients with class II-IV HF, LVEF < 45%, independently of the HF etiology, as compared to HT patients.

Resumo Fundamentos: A insuficiência cardíaca (IC) representa um grave problema de saúde pública pela alta morbimortalidade e custos envolvidos, exigindo uma melhor compreensão de sua evolução. Em sua patogênese, complexa e multifatorial, a hiperatividade simpática ocupa relevante papel. Considerando que a disfunção simpática está presente já nas fases iniciais da cardiopatia chagásica crônica (CCC), frequentemente associando-se a um pior prognóstico, supomos que pudesse ser mais grave na CCC que nas demais etiologias (não-CCC). Objetivos: Avaliar a disfunção simpática cardíaca (123I-MIBG) da IC, comparando-se os portadores de CCC aos não-CCC, utilizando os pacientes transplantados cardíacos (TC) como parâmetro de coração desnervado. Métodos: Estudamos 76 pacientes com IC classe funcional II-VI, sendo 25 CCC (17 homens), 25 não-CCC (14 homens) e 26 TC (20 homens), pela cintilografia cardíaca (123I-MIBG), estimando-se a captação (HMR) precoce e tardia e o washout cardíaco (Wc%). Nas análises estatísticas, o nível de significância foi de 5%. Resultados: Os valores da HMR precoce e da tardia foram 1,73 ± 0,24 e 1,58 ± 0,27, respectivamente, na CCC, e 1,62 ± 0,21 e 1,44 ± 0,16 na não-CCC (p = NS), sendo, porém, mais elevados nos TC (p < 0,001). Os valores de Wc% foram 41,65 ± 21,4 (CCC), 47,37 ± 14,19% (não-CCC) e 43,29 ± 23,02 (TC), p = 0,057. Os valores de HMR tardia apresentaram correlação positiva fraca com a fração de ejeção de ventrículo esquerdo (FEVE) na CCC e na não-CCC (r = 0,42 e p = 0,045; e r = 0,49 e p = 0,015, respectivamente). Conclusão: Evidenciou-se a presença de hiperatividade simpática (123I-MIBG) em pacientes com IC classe II-IV, FEVE < 45%, independentemente da etiologia da IC, quando comparados aos pacientes TC.

Projeto imagem da semana / Image of the week project

O ensino médico, de modo geral, envolve a associação entre teoria e prática, o que é de particular importância no ensino da área de diagnóstico por imagem. A metodologia do ensino baseado em problemas, associada ao ensino a distância, permite alcançar um público amplo e estimular o raciocínio clínico, o espírito crítico e o autodidatismo, características essenciais ao profissional médico. Nesse âmbito, surgiu o projeto "Imagem da Semana", que consiste em uma página no site da Faculdade de Medicina aberta ao público, na qual semanalmente é publicado um novo caso clínico, associado a uma imagem e a uma pergunta objetiva. O visitante é encorajado a responder à pergunta corretamente para ter acesso à discussão do caso e aprender mais sobre o diagnóstico e os diagnósticos diferenciais da doença abordada. O projeto tem sido muito bem recebido pela comunidade acadêmica, servindo também para a educação continuada de médicos generalistas e especialistas, além de divulgar o conhecimento produzido na universidade. Acreditamos que a democratização do conhecimento é um passo importante rumo à melhoria do ensino médico.

It is known that the teaching of medicine involves associating theory and practice. This is of particular importance in the teachings of diagnosis by image. The methodology of problem based learning allows for the reaching of a wide range of people and stimulates clinical and critical thinking and self teaching, essential characteristics of every physician. Having this in mind, we started the project "Image of the Week". The project consists of an internet page in the medical school's website where every week a case and an image is published, together with an objective question. The visitor is encouraged to answer the question correctly to gain access to the case discussion and be able to learn more about the diagnosis and differential diagnosis of the presented disease. The project has been very successful in the academic community and has also been used for continued education by general practitioners and medical specialists, besides sharing the knowledge produced in the University. We believe that the democratization of knowledge is a big step towards the improvement of medical teaching.