RESUMO Antecedentes: Uma das potenciais fontes embólicas no acidente vascular cerebral (AVC) de origem indeterminada é o forame oval patente (FOP). Objetivo: O objetivo do presente estudo foi identificar as características do shunt direita-esquerda em paciente com AVC de etiologia indeterminada, presumidamente embólica, e comparar tais características com pacientes apresentando AVC por outras causas não embólicas. Métodos: Trata-se de um estudo retrospectivo com 168 pacientes com AVC e forame oval patente, separados em dois grupos: AVC embólico de etiologia indeterminada e AVC por outras causas não embólicas. Todos os pacientes foram submetidos a Doppler transcraniano, para avaliar a presença de shunt direita-esquerda por meio do teste de embolia paradoxal. Além da quantificação de microbolhas, também foi avaliada a presença de shunt em repouso e sob manobra de Valsalva. Resultado: Do total, 96 pacientes foram incluídos no primeiro grupo (AVC indeterminado) e 72, no segundo grupo (AVC não embólico). No primeiro grupo, 65 pacientes exibiram shunt com passagem de mais de 10 microbolhas (67,5%), enquanto no segundo grupo isso aconteceu em 51,4% (p=0,038) dos casos. Além disso, 75 pacientes (78,1%) do primeiro grupo tiveram teste positivo ao repouso, comparados com 42 pacientes (58,3%) no segundo grupo (p=0,007). Conclusão: O presente estudo demonstrou que até 70% dos pacientes com AVC de etiologia indeterminada e forame oval apresentaram shunts maiores; em mais de 75%, houve passagem de microbolhas ao repouso. Esses achados sugerem que as características do shunt, como quantidade de microbolhas e passagem ao repouso, devem ser levadas em consideração na avaliação do FOP como possível mecanismo subjacente ao AVC.

Abstract Background: Patent foramen ovale (PFO) has been considered a potential mechanism of embolic stroke of undetermined origin. Objective: The aim of the present study was to identify the features of the right-to-left shunt (RLS) in patients with undetermined embolic ischemic stroke and compare them with those of patients with non-cardioembolic ischemic stroke. Methods: A retrospective study was conducted with 168 patients with stroke and RLS separated into the following two groups: the undetermined embolic stroke group (UES group) and non-cardioembolic stroke group (NCES group). All patients were assessed by transcranial Doppler to evaluate the presence and quantification of microembolic signals (MES) at rest and under Valsalva maneuver. Results: Of all patients evaluated in the current study, 96 were included in the UES group and 72 in the NCES group. In the UES group, 65 patients had RLS with ≥10 MES (67.7%), which was higher than that observed in the NCES group (51.4%, p=0.038). According to the moment of the cardiac cycle, 75 patients (78.1%) in the UES group had a positive test at rest compared to 42 (58.3%) in the NCES group (p=0.007). Conclusions: The current study demonstrated that almost 70% of patients with undetermined embolic stroke and PFO presented a large RLS and more than 75% had RLS at rest. These findings suggest that the size of the shunt should be taken into account when evaluating whether PFO could be a possible mechanism underlying cryptogenic stroke.

Abstract Background: Stroke related to atrial fibrillation (AF) is associated with high recurrence and mortality rates. Embolic Stroke of Undetermined Source (ESUS) is associated with fewer vascular risk factors, less disability, and a high recurrence rate. Objective: To compare risk factors, functional outcomes and the occurrence of primary endpoint (a composite of recurrent stroke, cardiovascular death, and myocardial infarction) between AF stroke and ESUS patients. Method: A retrospective analysis was conducted including all consecutive patients with first-ever ischemic stroke admitted to the Hospital de Clinicas (Clinical Hospital) of the Federal University of Paraná from October 2012 to January 2017 (n=554). There were 61 patients with stroke due to AF and 43 due to ESUS. Both groups were compared for demographic characteristics and vascular risk factors. Logistic regression models were performed to assess the impact of each variable on the primary endpoint in a 12-month follow-up. Statistical significance was considered for p-values < 0.05. Results: ESUS patients, as compared to AF patients, were younger and more likely to be smokers. ESUS patients presented a mean CHADS2VASc score of 4, while the AF group presented a score of 5 (p <0.001). The primary endpoint was observed in 9 (20.9%) ESUS and 11 (18.0%) AF patients over a 12-month period (p=0.802). Higher glucose levels upon hospital admission (p=0.020) and a higher modified Rankin Scale upon hospital discharge (p=0.020) were predictors of the primary endpoint occurrence. Conclusion: AF and ESUS stroke patients presented very similar independence rates upon hospital discharge and outcomes after 12 months, despite some baseline differences, including stroke recurrence, vascular death, and myocardial infarction.

RESUMO Introdução: A sífilis é uma doença endêmica, especialmente em países de baixa e média renda, com acometimento vascular descrito em grandes vasos (aortite), porém nenhuma relação clara foi reconhecida em paciente com acidente vascular cerebral, exceto para aqueles com sífilis meningovascular. Objetivos: Investigar a relação entre história positiva de sífilis determinada pelo status sorológico e o mecanismo do acidente vascular cerebral isquêmico, particularmente doença de pequenos vasos. Métodos: Ao todo, 269 pacientes com AVC isquêmico foram testados para sífilis. Pacientes com diagnóstico de neurossífilis foram excluídos. Todos os pacientes foram classificados segundo o fenótipo ASCOD quando a doença de pequenos vasos era o mecanismo causal provável (S1) ou não-pequenos vasos quando este mecanismo era incerto (S2), pouco provável (S3) ou não detectado (S0). Resultados: O teste para sífilis foi positivo em 32 (12%) pacientes. Quando comparados, pacientes com sorologia positiva e o grupo com teste não reagente, a única diferença significativa foi a doença de pequenos vasos como mecanismo causal (S1) em pacientes com sorologia positiva: 9 (28%) vs. 22 (9%), p<0.01. Conclusão: O presente estudo mostra que o teste sorológico positivo para sífilis tem maior ocorrência em pacientes com o primeiro AVC isquêmico com a doença de pequenos vasos como um mecanismo causal possível. Tal achado pode estar relacionado à disfunção endotelial que ocorre durante a sífilis.

ABSTRACT Background: Syphilis is an endemic disease, particularly in low- and middle-income countries, with vascular involvement in large vessels (aortitis), but no clear relationship with stroke patients, except for those who presented with meningovascular neurosyphilis. Objective: To investigate the relationship between a positive history of syphilis determined by serological testing and ischemic stroke etiology, particularly small vessel disease (SVD). Methods: In total, 269 first-ever ischemic stroke patients admitted to the stroke unit were tested for syphilis. Patients with neurosyphilis were excluded. All patients were classified according to the ASCOD phenotyping as SVD — when SVD was the potential causal mechanism (S1) — or non-SVD — when SVD was uncertain (S2), unlike (S3), or not detected (S0). Results: Syphilis was positive in 32 (12%) patients. When comparing patients with positive and negative serology, the only significant difference was SVD as the causal mechanism (S1) in patients with positive results: 9 (28%) vs. 22 (9%), p<0.01. Conclusion: The current study showed that the frequency of positive syphilis serological test was higher in patients with first-ever ischemic stroke and SVD as the potential causal mechanism. This finding could be related to the endothelial dysfunction occurring in syphilis.