Stroke history and Chagas disease are independent predictors of silent cerebral microembolism in patients with congestive heart failure.

BACKGROUND: Chagas disease is endemic in South and Central America, where 18 million individuals are infected by Trypanosoma cruzi, causing congestive heart failure (CHF) and cardioembolic stroke. Transcranial Doppler (TCD) is able to detect real-time microembolic signals (MES) to the brain vessels and may represent a surrogate marker of stroke risk. We aimed to determine predictors of MES in a population of patients with CHF. METHODS: Consecutive CHF patients from a university-based cardiomyopathy clinic underwent TCD recording of the middle cerebral artery for 60 min by a single investigator who was blinded to all clinical data including cardiomyopathy etiology. Predictors of MES were sought by multivariable logistic regression analysis. RESULTS: From April 2004 to February 2009, 144 patients were studied, including 62 (44.6%) patients with Chagas disease. MES were detected in 9 (6.2%) patients and were more frequent in patients with Chagas disease than in patients with other causes of CHF (12.9 vs. 1.2%, p = 0.005). In multivariate analysis corrected for age and left-ventricular ejection fraction, predictors of MES were Chagas disease (odds ratio = 1.15, 95% confidence interval = 1.05-1.26, p = 0.004) and stroke history (odds ratio = 1.27, 95% confidence interval = 1.08-1.50, p = 0.005). CONCLUSIONS: Chagas disease and stroke history are risk factors for MES independent of cardiac disease severity. Other mechanisms besides structural cardiac disease may be operative, increasing embolic risk in Chagas disease.

Chagas disease is independently associated with brain atrophy.

Chagas disease (CD) remains a major cause of cardiomyopathy and stroke in developing countries. Brain involvement in CD has been attributed to left ventricular dysfunction, resulting in chronic brain ischemia due to hypoperfusion and/or embolic infarcts. However, cognitive impairment in CD may occur independently of cardiac disease. Therefore, we aimed to investigate head computed tomography (CT) findings in patients with Chagas disease cardiomyopathy (CDC) in comparison with other cardiomyopathies (OC). We studied 73 patients with CDC (n = 41) or OC (n = 32) matched for age and gender. These patients underwent head CT, rated by an investigator blinded to all clinical information. Head CT was rated for the presence of lacunar or territorial infarcts, as well as for measuring the total volumes of the brain, cerebellum and ventricles. Total brain volume was smaller in CDC as compared to OC patients (1,135 +/- 150 vs. 1,332 +/- 198 cm(3), P < 0.001). Cerebellar and ventricular volumes did not differ between the groups. The prevalence of brain infarcts did not differ significantly between the groups. Chagas disease was the only independent predictor of brain atrophy in the multivariable analysis (OR = 1.38; 95% CI = 1.06-1.79, P = 0.017). Chagas disease is associated with brain atrophy independent of structural cardiac disease related to cardiomyopathy. Brain atrophy, rather than multiple infarcts, may represent the main anatomical substrate of cognitive impairment in Chagas disease.

Cognitive dysfunction in chronic Chagas disease cardiomyopathy.

Chagas disease (CD) remains a major cause of stroke in developing countries, but cognitive repercussion of CD has not been well studied. OBJECTIVE: To compare the frequency and pattern of cognitive dysfunction in patients with CD cardiomyopathy (CDC) and other cardiomyopathies (OC). METHODS: We studied 37 patients with CDC and 42 patients with OC with similar age, educational level and cardiac systolic function. Cognitive tests were applied to both groups by a single examiner blinded to CD status. Logistic regression multivariable models were constructed to ascertain predictors of cognitive dysfunction for each test. RESULTS: Cognitive dysfunction was detected in 9 (24%) CDC patients and 6 (14%) OC patients by Mini Mental State Exam (MMSE) corrected for educational level. Independent predictors of abnormal MMSE (p<0.05) included stroke history (OR=5.51; 95% CI=1.27-24.01) and digoxin use (OR=0.23, 95% CI=0.06-0.89), while CD showed a trend toward statistical significance (OR=4.63; 95% CI=0.87-24.73, p=0.07). Delayed recall of Rey's Complex Figure Test was significantly worse in CD patients, where this remained a significant predictor in the multivariable analysis (OR=4.67; 95% CI=1.23-17.68). CONCLUSIONS: Cognitive dysfunction is frequent in Chagas disease and should be considered as an outcome measure in Chagas disease studies.

A doença de Chagas (DC) permanence uma causa importante de acidente vascular cerebral em países em desenvolvimento, mas a repercussão cognitiva dessa doença não tem sido bem estudada. OBJETIVO: Comparar a frequência e padrão de disfunção cognitiva em pacientes com cardiomiopatia associada à DC (CDC) em comparação com outras cardiomiopatias (OC). MÉTODOS: Foram estudados 37 pacientes com CDC e 42 portadores de OC com idade, nível de instrução e função sistólica cardíaca semelhantes. Testes cognitivos foram realizados em ambos os grupos por um único investigador cegado quanto ao diagnóstico de DC. Modelos de regressão logística multi-variável foram construídos para detectar preditores de disfunção cognitiva para cada teste. RESULTADOS: Disfunção cognitiva foi detectada em 9 (24%) pacientes com CDC e 6 (14%) com OC pelo Mini Exame do Estado Mental (MEEM) corrigido pelo nível de instrução. Preditores independentes de MEEM anormal (p<0,05) foram: história de AVC (OR=5,51; IC 95%=1,27­24,01) e uso de digoxina (OR=0,23, IC 95%=0,06­0,89); DC mostrou tendência a significância estatística (OR=4,63; IC 95%=0,87­24,73, p=0,07). Pacientes com CDC apresentaram pior desempenho na evocação tardia da figura complexa de Rey. Neste teste, a DC se manteve um preditor significante de disfunção cognitiva na análise multivariável (OR=4,67; IC 95%=1,23­17,68). CONCLUSÕES: Disfunção cognitiva é frequente na doença de Chagas e deve ser considerada como desfecho quantificado nos estudos da doença de Chagas.