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Background: The investigation of ischemic stroke etiology is commonly limited to the heart and extracranial vessels. However, the diagnosis of intracranial stenosis may carry important therapeutic implications. We aimed to determine the prevalence of intracranial stenosis and compare the predictors of intracranial and extracranial stenosis in patients with ischemic stroke. Methods: Consecutive patients admitted to a university-based outpatient stroke clinic were submitted to 64-slice CT angiography (CTA) of the intracranial and extracranial brain vessels. Clinical, demographic and laboratory characteristics were compared between patients with or without a critical (>70%) intracranial or extracranial arterial stenosis. Ankle-brachial index (ABI) was measured to quantify peripheral arterial disease, defined by a low ABI (<=0.9). Multivariable logistic regression analysis was performed including variables with a possible (P<0.1) association in univarible analyses, searching for predictors of intracranial and extracranial stenosis. Results: One hundred-five patients were studied, mean age 59 +/- 14 years, 55% female. Intracranial stenosis occurred in 13% of the sample, while extracranial stenosis occurred in 14%. Clinical characteristics such as age, sex and major cerebrovascular risk factors did not discriminate between patients with or without intracranial stenosis. No association was found between intracranial and extracranial stenosis. The predictors of intracranial stenosis in the multivariable analysis were low ABI (OR=21.2; 95% CI 1.8-250.0) and abdominal circumference (OR=1.11 for every 1 cm increase; 95% CI=1.01-1.22), while the only predictor of extracranial stenosis was smoking history (OR 1.02 for every 1 pack-year; 95% CI 1.01-1.04). Low ABI was the best screening tool for intracranial stenosis (sensitivity 89%, specificity 70%, positive predictive value 32%, negative predictive value 98%). Conclusion: Classical cerebrovascular risk factors do not discriminate between patients with or without intracranial stenosis. Abdominal circumference and ABI may be useful clinical screening tools for intracranial stenosis.

Introduction: Chagas disease is a major cause of cardiomyopathy and cardioembolic stroke in Latin America. However, stroke has been reported in patients without cardiomyopathy. Hypothesis: We aimed to determine if Chagas is associated with combined events of stroke or death. Methods: Open hospital-based cohort of consecutive stroke-free individuals with suspected heart failure or asymptomatic Chagas (positive serologic test only) followed from February, 2002 to July, 2015. Endpoint was combined events of stroke or death. Potential confounders included age, sex, cerebrovascular risk factors, echocardiographic left ventricular ejection fraction and EKG rhythm, adjusted in a multivariable Cox regression. Results: Participants were 556 individuals, mean age 55 (+/- 12) years, followed for a mean of 2.3 (+/- 1.5) years, leading to 1297 person-years of observation. Chagas was present in 288 (52%) and cardiomyopathy in 444 (80%) individuals at baseline. There were 2.2 strokes and 8.4 stroke or death events per 100 person-years among patients with Chagas, when compared to 1.3 strokes and 6.5 stroke or death events per 100 person-years among non-chagasic patients. In the model adjusted for potential confounders, Chagas remained an independent predictor of stroke or death (hazard ratio = 2.52; 95% confidence interval = 1.29 - 4.95, p=0.007). Conclusions: Chagas disease is associated a 2.5-fold increase in the rate of early stroke or death independently of cardiac disease. Non-cardioembolic mechanisms for stroke should be further investigated in this population.

Background: Chagas disease (CD) is a major cause of stroke and cardiomyopathy in Latin America. Brain atrophy has been associated with CD independently of stroke or cardiac disease, but cognitive effects of this finding has not been explored. Our objective was to compare cognitive impairment in patients with CD and non-CD cardiomyopathy; and to correlate these findings with quantification of brain and cerebellar volumes. Methods: Consecutive patients from a cardiomyopathy clinic without a history of stroke were submitted to a structured interview including clinical information and cognitive tests (Mini Mental State Exam - MMSE, digit span, clock drawing test, delayed memory test). Brain MRI was performed and brain and cerebellar volumes quantified by ITK-SNAP software. MR spectroscopy quantified N-acetylaspartate (NAA)-, choline- and myoinositol-to-creatine ratios. Results: 118 patients were recruited; mean age 54 +/- 12 years, 53% female, 49% with CD. Despite a better systolic cardiac function by echocardiography (ejection fraction 45 vs 38%, P=0.006), patients with CD performed worse on various cognitive tests (MMSE, delayed memory test and clock drawing test, P<0.01). Cerebellar volumes, but not brain volumes, were significantly smaller in CD vs non-CD cardiomyopathy (125 vs 136ml, P=0.035) and correlated with clock drawing test results (rS=0.219, P=0.024). In a multivariable analysis, delayed memory impairment, NAA/creatine ratio and cerebellar volumes were independently associated with Chagas disease. Conclusions: Cognitive dysfunction in CD occurred independently of cardiac disease severity and was associated with cerebellar atrophy.