Amnésia global transitória: uma síndrome enigmática

• Autor(a) principal: Mariana Martins Lima de Sardo Patrício
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://hdl.handle.net/10216/134536
• topic: Ciências médicas e da saúde; Medical and Health sciences

Transient global amnesia (TGA) is a clinical syndrome characterized by an inability to form new memories. This amnesic state can last up to 24 hours and gradually disappears without any treatment and with no sequels left. Concerning its etiology, TGA still remains poorly understood. In this review, an updated perspective regarding TGA risk factors, triggers, pathophysiology and patient management will be presented. For this review, 290 articles were selected. A PubMed literature research was conducted with the term "Transient global amnesia" and was limited to publications written in English since 2010. Additionally, relevant articles referenced in the initial database were also included. The results indicate that TGA incidence between genders is equivalent. However, the age of the individuals has shown to be a major risk factor since this condition affects predominantly people over 50 years old. Several other epidemiologic correlations to TGA were found such as migraine history, Valsalva maneuver preceding an episode and psychiatric disorders. Nevertheless, none of these factors is consistently present. The TGA diagnosis is essentially clinical. Neuroimaging studies may be used particularly in emergency department context for the differential diagnosis with vascular disease and for research projects. The TGA pathophysiology is a very controversial topic and has led to a vast diversity of explanatory hypothesis. Hippocampus dysfunction is globally recognized as the underlying mechanism to all the conceptual models described so far. Due to its self-limited course, patient management requires clinical vigilance until complete resolution of symptoms and providence of explanations to the patients and their family or care-givers. In conclusion, TGA is considered a benign entity with a low recurrence rate. In order to improve these patients management and to prevent future episodes, this study highlights that further investigation is needed concerning its etiology and potential long-term effects. Key words: Amnesia; Transient global amnesia; Hippocampus; Memory; Cognition; Cognitive diseases