-Cognitive symptoms are common in patients with congestive heart failure (CHF) and are usually attributed to low cerebral blood flow. In the present study, we aimed to evaluate global cognitive function (Mini Mental State Exam -MMSE) in relation to both cardiac function (evaluated by echocardiogram) and cere b rovascular hemodynamics (evaluated by transcranial Doppler -TCD) in CHF patients. In 83 patients studied, no correlation was found between echocardiographic parameters and MMSE scores. In contrast, a significant correlation was found between right middle cerebral art e ry (RMCA) mean flow velocity and MMSE score (r=0.231 p=0.039), as well as between RMCA pulsatility index and MMSE score (r s = -0.292 p=0.015). After excluding patients with a previous history of stroke, only RMCA pulsatility index c o rrelated with MMSE score (r s =-0,314 p=0,007). The relationship between high cere b rovascular re s i s t a n c e and worse cognitive scores suggest that microembolism may be responsible for a significant pro p o rtion of cognitive symptoms in CHF patients.KEY WORDS: transcranial Doppler, congestive heart failure, cognitive dysfunction cere b rovascular disord e r s .Disfunção cognitiva na insuficiência cardíaca congestiva: evidência de etiologia micro e m b ó l ica ao Doppler transcraniano RESUMO -Sintomas cognitivos são comuns em pacientes com insuficiência cardíaca congestiva (ICC) e são geralmente atribuídos a um regime de baixo fluxo sanguíneo cerebral. Neste estudo, objetivamos avaliar a função cognitiva global (Mini Exame do Estado Mental -MEEM) em pacientes com ICC e sua relação com o grau de disfunção cardíaca (avaliada pelo ecocardiograma) e a hemodinâmica cerebral (avaliada pelo Doppler transcraniano -DTC). Em 83 pacientes estudados, nenhuma correlação foi encontrada entre a pontuação no MEEM e parâmetros ecocardiográficos. Em contraste, uma correlação significativa foi encontrada entre a velocidade média na artéria cerebral média direita (ACMD) e a pontuação no MEEM (r=0,231 p=0,039), assim como entre o índice de pulsatilidade na ACMD e a pontuação no MEEM (r s =-0,292 p=0,015). Após excluir pacientes com histórico prévio de acidente vascular encefálico, somente o índice de pulsatilidade na ACMD manteve uma correlação com a pontuação no MEEM (r s =-0,314 p=0,007). A relação entre maior resistência vascular cerebral e pior desempenho cognitivo sugere que microembolia pode ser re s p o nsável por uma proporção significativa de sintomas cognitivos em pacientes com ICC. PALAVRAS-CHAVE: Doppler transcraniano, insuficiência cardíaca congestiva, acidente vascular cerebral.

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.

Chagas disease (CD) remains a major cause of stroke in developing countries, but cognitive repercussion of CD has not been well studied.ObjectiveTo compare the frequency and pattern of cognitive dysfunction in patients with CD cardiomyopathy (CDC) and other cardiomyopathies (OC).MethodsWe 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.ResultsCognitive 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).ConclusionsCognitive dysfunction is frequent in Chagas disease and should be considered as an outcome measure in Chagas disease studies.

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.