Electrical impedance tomography in pulmonary arterial hypertension.

The characterization of pulmonary arterial hypertension (PAH) relies mainly on right heart catheterization (RHC). Electrical impedance tomography (EIT) provides a non-invasive estimation of lung perfusion that could complement the hemodynamic information from RHC. To assess the association between impedance variation of lung perfusion (ΔZQ) and hemodynamic profile, severity, and prognosis, suspected of PAH or worsening PAH patients were submitted simultaneously to RHC and EIT. Measurements of ΔZQ were obtained. Based on the results of the RHC, 35 patients composed the PAH group, and eight patients, the normopressoric (NP) group. PAH patients showed a significantly reduced ΔZQ compared to the NP group. There was a significant correlation between ΔZQ and hemodynamic parameters, particularly with stroke volume (SV) (r = 0.76; P < 0.001). At 60 months, 15 patients died (43%) and 1 received lung transplantation; at baseline they had worse hemodynamics, and reduced ΔZQ when compared to survivors. Patients with low ΔZQ (≤154.6%.Kg) presented significantly worse survival (P = 0.033). ΔZQ is associated with hemodynamic status of PAH patients, with disease severity and survival, demonstrating EIT as a promising tool for monitoring patients with pulmonary vascular disease.

Post-mortem histological pulmonary analysis in patients with HIV/AIDS.

OBJECTIVES: Certain aspects of pulmonary pathology observed in autopsies of HIV/AIDS patients are still unknown. This study considers 250 autopsies of HIV/AIDS patients who died of acute respiratory failure and describes the demographic data, etiology, and histological pulmonary findings of the various pathologies. METHODS: The following data were obtained: age, sex, and major associated diseases (found at the autopsy). Pulmonary histopathology was categorized as: diffuse alveolar damage; pulmonary edema; alveolar hemorrhage; and acute interstitial pneumonia. Odds ratio of the HIV/AIDS-associated diseases developing a specific histopathological pattern was determined by logistic regression. RESULTS: A total of 197 men and 53 women were studied. The mean age was 36 years. Bacterial bronchopneumonia was present in 36% (91 cases) and Pneumocystis jiroveci pneumonia in 27% (68) of patients. Pulmonary histopathology showed acute interstitial pneumonia in 40% (99), diffuse alveolar damage in 36% (89), pulmonary edema in 13% (33), and alveolar hemorrhage in 12% (29) of patients. Multivariate analysis showed a significant and positive association between Pneumocystis jiroveci pneumonia and acute interstitial pneumonia (Odds ratio, 4.51; 95% CI, 2.46-8.24; p<0.001), severe sepsis and/or septic shock and diffuse alveolar damage (Odds ratio, 3.60; 95% CI, 1.78-7.27; p<0.001), and cytomegalovirus and acute interstitial pneumonia (Odds ratio, 2.22; 95% CI, 1.01-4.93; p=0.05). CONCLUSIONS: This report is the first autopsy study to include demographic data, etiologic diagnosis, and respective histopathological findings in patients with HIV/AIDS and acute respiratory failure. Further studies are necessary to elucidate the complete pulmonary physiopathological mechanism involved with each HIV/AIDS-associated disease.

Post-mortem histological pulmonary analysis in patients with HIV/AIDS

OBJECTIVES: Certain aspects of pulmonary pathology observed in autopsies of HIV/AIDS patients are still unknown. This study considers 250 autopsies of HIV/AIDS patients who died of acute respiratory failure and describes the demographic data, etiology, and histological pulmonary findings of the various pathologies. METHODS: The following data were obtained: age, sex, and major associated diseases (found at the autopsy). Pulmonary histopathology was categorized as: diffuse alveolar damage; pulmonary edema; alveolar hemorrhage; and acute interstitial pneumonia. Odds ratio of the HIV/AIDS-associated diseases developing a specific histopathological pattern was determined by logistic regression. RESULTS: A total of 197 men and 53 women were studied. The mean age was 36 years. Bacterial bronchopneumonia was present in 36 percent (91 cases) and Pneumocystis jiroveci pneumonia in 27 percent (68) of patients. Pulmonary histopathology showed acute interstitial pneumonia in 40 percent (99), diffuse alveolar damage in 36 percent (89), pulmonary edema in 13 percent (33), and alveolar hemorrhage in 12 percent (29) of patients. Multivariate analysis showed a significant and positive association between Pneumocystis jiroveci pneumonia and acute interstitial pneumonia (Odds ratio, 4.51; 95 percent CI, 2.46 - 8.24; p < 0.001), severe sepsis and/or septic shock and diffuse alveolar damage (Odds ratio, 3.60; 95 percent CI, 1.78 -7.27; p < 0.001), and cytomegalovirus and acute interstitial pneumonia (Odds ratio, 2.22; 95 percent CI, 1.01 - 4.93; p = 0.05). CONCLUSIONS: This report is the first autopsy study to include demographic data, etiologic diagnosis, and respective histopathological findings in patients with HIV/AIDS and acute respiratory failure. Further studies are necessary to elucidate the complete pulmonary physiopathological mechanism involved with each HIV/AIDS-associated disease.

Isquemia miocárdica silenciosa / Silent myocardial ischemia

A isquemia miocárdica é o evento fisiopatológico final da doença arterial coronária (DAC). Quando desprovida de sintomatologia é denominada "isquemia miocárdica silenciosa", sendo a responsável pela maior parte dos eventos isquêmicos totais. Ainda permanecem incertos os porquês da näo percepçäo dolorosa ("angina") de certos episódios isquêmicos, bem como dos mecanismos fisiopatológicos que as desencadeiam. Claro está, no entanto, que os eventos silenciosos e sintomáticos näo se diferem quanto às alteraçöes miocárdicas estruturais e funcionais. O diagnóstico de isquemia silenciosa se estabelece quando da detecçäo de alteraçöes objetivas e características de dano miocárdico isquêmico. Dentre os métodos se configuram, principalmente, a eletrocardiografia de esforço, a monitorizaçäo eletrocardiográfica ambulatorial, o teste de perfusäo com tálio-201 e o ecocardiograma de esforço. Há outros, porém de menor utilizaçäo. Destaca-se a isquemia silenciosa pela sua importante relaçäo com o prognóstico dos portadores de DAC. Muitos estudos relatam participaçäo significativa daquela nos variados desfechos da DAC (angina, infarto agudo do miocárdio e morte súbita). O enfoque terapêutico varia para cada paciente, podendo iniciar-se com a mudança do estilo de vida (alteraçäo dos fatores de risco). A terapêutica medicamentosa se baseia na utilizaçäo de drogas antiisquêmicas (nitratos, beta-bloqueadores e antagonistas dos canais de cálcio) e antiplaquetários. o tratamento mais agressivo inclui a angioplastia coronária, a colocaçäo de stents e a cirurgia de revascularizaçäo do miocárdio.