Background:Patent foramen ovale (PFO) is a congenital anatomical variant which is associated with strokes in young adults. Contrary to vascular risk factors and atherosclerosis, a PFO is present from birth. However, it is completely unknown how an anatomical structure that is already present at birth in a large proportion of the population, can convert into a PFO that causes stroke in a few. Recent studies reported a significant association between certain trigger factors and ischemic stroke in young adults. This study aims to investigate these triggers in PFO-associated stroke.Methods:The ODYSSEY Study, a multicenter prospective cohort study between 2013 and 2021, included patients aged 18-49 years experiencing their first-ever ischemic event. Participants completed a questionnaire about exposure to potential trigger factors. A case-crossover design was used to assess the relative risks (RR) with 95% confidence intervals (95% CI). The primary outcome was the relative risk of potential trigger factors for PFO-associated stroke.Results:1043 patients completed the questionnaire and had an ischemic stroke of which 124 patients had a PFO-associated stroke (median age 42.1 years, 45.2% men). For patients with PFO-associated stroke the RR was 26.0 (95% CI 8.0-128.2) for fever, 24.2 (95% CI 8.5-68.7) for flu-like disease and RR 3.31 (95% CI 2.2-5.1) for vigorous exercise.Conclusion:In conclusion, flu-like disease, fever and vigorous exercise may convert an asymptomatic PFO into a stroke causing PFO in young adults.

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卵圆孔未闭相关中风患者的触发因素：病例交叉研究

背景：卵圆孔未闭（PFO）是一种先天性解剖变异，与年轻人中风有关。与血管危险因素和动脉粥样硬化相反，PFO 从出生起就存在。然而，目前还完全不知道大部分人出生时就存在的解剖结构如何转化为卵圆孔未闭（PFO），导致少数人中风。最近的研究报告了某些触发因素与年轻人缺血性中风之间的显着关联。本研究旨在调查 PFO 相关中风的这些触发因素。方法：ODYSSEY 研究是一项 2013 年至 2021 年的多中心前瞻性队列研究，纳入了首次发生缺血事件的 18-49 岁患者。参与者完成了一份有关潜在触发因素暴露情况的调查问卷。使用病例交叉设计来评估具有 95% 置信区间 (95% CI) 的相对风险 (RR)。主要结局是 PFO 相关中风潜在触发因素的相对风险。 结果：1043 名患者完成了问卷调查，并患有缺血性中风，其中 124 名患者患有 PFO 相关中风（中位年龄 42.1 岁，45.2% 男性）。对于 PFO 相关中风患者，发烧的 RR 为 26.0 (95% CI 8.0-128.2)，流感样疾病的 RR 为 24.2 (95% CI 8.5-68.7)，剧烈运动的 RR 为 3.31 (95% CI 2.2-5.1)结论：总而言之，流感样疾病、发烧和剧烈运动可能会将无症状 PFO 转变为导致年轻人 PFO 的中风。