Rosália Moraes Torres

The Valsalva maneuver in Chagas disease patients without cardiopathy

BACKGROUND The Valsalva maneuver is a simple and reliable test of parasympathetic heart control that can also be used as a trigger of cardiac arrhythmia. Few studies are available about the Valsalva maneuver in Chagas disease patients without cardiac involvement and their results are contradictory. In a cross-sectional study, we compared Chagas disease patients without cardiac involvement and normal individuals using the Valsalva maneuver in order to study the vagal cardiac control and the occurrence of cardiac arrhythmia in the early phase of Chagas disease. METHODS Fifty-nine patients with Chagas disease without cardiac involvement and 37 controls were submitted to a carefully standardized Valsalva maneuver. Cardiac vagal control was assessed by the Valsalva ratio and the occurrence of cardiac arrhythmia was recorded and coded. RESULTS The two groups were comparable in terms of left ventricular ejection fraction and left ventricular end-diastolic dimension. When compared to the control group, patients with Chagas disease had significantly lower Valsalva ratios (1.81+/-0.41 versus 2.01+/-0.41, P=0.017) which were not significantly correlated with age, left ventricular function or the presence of radiological esophageal abnormalities. Atrioventricular block (mainly 2nd degree Mobitz type I) occurred exclusively in Chagas disease patients (15,6%, P=0.021) and may indicate an early involvement of the AV node. Premature ventricular contraction was more frequent in Chagas disease patients (16.9% versus 8.1%, P=0.217), although the difference was not statistically significant. CONCLUSION The Valsalva maneuver is a useful test to detect early vagal dysfunction in Chagas disease patients without cardiac involvement.

Low Doses of Simvastatin Therapy Ameliorate Cardiac Inflammatory Remodeling in Trypanosoma cruzi-Infected Dogs

Chagas cardiomyopathy remodeling is based on the presence of Trypanosoma cruzi in heart tissue and on the complex inflammatory response leading to a myocardium fibrosis and alterations in conductive and functional heart parameters. This study aims to evaluate Simvastatin on the inflammatory response and heart functionality using dogs infected with Y strain of T. cruzi. Animals were treated daily with Simvastatin (20 mg) for 6 months and submitted to clinical and immunopathological evaluations. Simvastatin reduced heart expression and serum levels of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) but not interleukin-10 (IL-10), possibly favoring blood parasitism but reducing inflammation and fibrosis in the left ventricle and right atrium. Simvastatin also ameliorated ejection fraction, diastolic diameter, and mass index of the left ventricle 6 months after infection. This study suggests that more investigation should be performed on the use of statins as a prophylactic therapy against cardiac remodeling because of their effects on modifying immune response and benefiting functional parameters in dogs with T. cruzi-induced ventricular dysfunctions.

Premature acute myocardial infarction in a child with nephrotic syndrome.

Abstract We report a case of acute myocardial infarction in a nephrotic child. A 7-year-old boy with a 4-year history of steroid-unresponsive nephrotic syndrome due to mesangial proliferation disease presented with acute vomiting and chest pain. An electrocardiogram showed ST elevation and pathological Q waves in leads consistent with anterior and septal myocardial infarction. Subsequent cardiac catheterization showed no evidence of atherosclerotic coronary artery disease, and thrombotic occlusion of the anterior descending coronary artery was the likely cause of the event. Myocardial scintigraphy showed extensive myocardial damage. The child had no long history of extreme hypercholesterolemia or hypertriglyceridemia. The case suggests that children with long-lasting nephrotic syndrome may be at increased risk for ischemic cardiovascular events, due to hyperlipidemia as well as a hypercoagulability state. The literature is reviewed regarding the relationship between nephrotic syndrome and the incidence of ischemic heart disease.

Avaliação da prevalência de hipertensão pulmonar na esclerose sistêmica

OBJETIVO: Avaliar a prevalencia da hipertensao pulmonar (HP) em pacientes com diagnostico de esclerose sistemica (ES) em acompanhamento num servico universitario terciario. METODOS: Foram avaliados 57 pacientes com ES, em acompanhamento no Servico de Reumatologia do HC-UFMG, atraves de exame clinico dirigido ao aparelho cardiorrespiratorio, testes de funcao pulmonar e ecodopplercardiograma (ECO). Foram considerados criterios diagnosticos para HP: pressao sistolica de arteria pulmonar (PSAP) > 40mmHg e/ou presenca de outros sinais diretos ou indiretos de HP identificados durante o ECO. RESULTADOS: Dezesseis pacientes (28%) apresentaram diagnostico de HP, sendo 13 com PSAP > 40 mmHg e 3 com sinais indiretos de HP; 8 pacientes apresentaram HP isolada e 8 HP secundaria a fibrose pulmonar. Em 9 pacientes havia sinais sugestivos de cor pulmonale ao ECO. Destes pacientes, 6 apresentaram PSAP > 40mmHg e 3 entre 35 e 40mmHg; dentre eles, 1 era assintomatico e 8 apresentavam sinais sugestivos de HP ao exame fisico. Dentre as variaveis clinicas e laboratoriais observadas, somente encontramos correlacao de HP com a velocidade de hemossedimentacao (VHS) elevada (p = 0,004). CONCLUSOES: A prevalencia de HP associada a ES encontrada neste estudo foi semelhante a outras da literatura, apesar das limitacoes nesta comparacao. A investigacao da HP atraves do ECO e uma pratica acessivel, de grande auxilio para o diagnostico precoce do acometimento vascular pulmonar. No entanto, e necessario que seja revisto o ponto de corte da PSAP medida ao ECO para diagnostico de HP relacionada a ES.