ABSTRACT Introduction: Stroke remains a major complication of cardiac surgery. Despite all efforts, the incidence of postoperative stroke remains as high as 6%. We aimed to investigate risk factors for ischemic stroke in a contemporary cohort of patients undergoing cardiac surgery. Methods: This is a retrospective cohort study of 678 consecutive adult patients who underwent cardiac surgery requiring cardiopulmonary bypass in a tertiary hospital in Brazil between July 1, 2011, and December 31, 2018. The primary outcome was the rate of early (perioperative and seven-day postoperative) stroke, defined as the occurrence of the outcome during the index admission. We developed a predictive model of stroke using the Poisson regression analysis with robust variance. Results: Postoperative stroke occurred in 24 patients (3.5%), 23 (3.3%) were ischemic, and 21 (3.0%) were diagnosed in the first 72 hours after surgical procedure. After multivariate analysis, the following factors were significantly associated with stroke: previous stroke/transient ischemic attack (relative risk [RR]=2.75; 95% confidence interval [CI], 1.11-6.82), carotid artery disease (RR=4.0; 95% CI, 1.43-11.0), previous atrial fibrillation (RR=3.26, 95% CI, 1.31-8.1), and postoperative platelets > 200,000/mm3 (RR=2.26; 95% CI, 1.01-5.1). Conclusion: We developed a contemporary model to determine risk predictors for stroke after cardiac surgery. This model may help clinicians to identify patients at risk and could be useful in clinical practice.

Resumo Nosso estudo descreve um caso fatal de flegmasia cerúlea dolens e trombose venosa maciça em um paciente usando regularmente rivaroxabana para o tratamento de trombose de seio venoso cerebral. A investigação laboratorial foi positiva para o anticoagulante lúpico. A evolução única do caso aumenta a possibilidade de uma síndrome de hipercoagulabilidade adquirida, bem como a positividade para o anticoagulante lúpico. Destacamos o fato de que o teste recomendado como primeira linha para o diagnóstico de anticoagulante lúpico (veneno de víbora de Russel diluído) é o mais afetado pela rivaroxabana, levando a uma alta prevalência de resultados falso-positivos. Também discutimos os potenciais diagnósticos para o presente caso e revisamos o estado da arte atual dos novos agentes de anticoagulação oral usados nessa situação incomum. Até o presente momento, não há recomendações para o uso de tais agentes como primeira opção na trombose de seios venosos cerebrais ou nas síndromes de hipercoagulação.

Abstract Our study describes a fatal case of phlegmasia cerulea dolens and massive venous thrombosis in a patient taking rivaroxaban regularly to treat cerebral venous sinus thrombosis. Blood tests samples were positive for lupus anticoagulant. The unique evolution of the case, as well as the positivity for lupus anticoagulant, raises the possibility of an acquired hypercoagulation syndrome. We highlight the fact that the test recommended as the first line for lupus anticoagulant diagnosis (dilute Russell viper venom time) is the most affected by rivaroxaban, leading to a high prevalence of false-positive results. We also discuss potential diagnoses for the current case and review the current state-of-the-art of use of the novel oral anticoagulation agents in this unusual situation. So far, there are no recommendations to use such agents as first options in cerebral venous sinus thrombosis or in hypercoagulation syndromes.