Introduction

Up to one-third of ischemic strokes remained cryptogenic despite extensive investigations. Atrial fibrillation may be detected in a significant proportion of patients with embolic stroke of undetermined source, particularly after the introduction of implantable loop recorder in clinical practice.

Methods

We retrospectively included all the consecutive patients with embolic stroke of undetermined source referred to our units in the period November 2013 to December 2018 and in which an implantable loop recorder was positioned within 6 months from stroke event. Prevalence and predictors of atrial fibrillation were investigated.

Results

One hundred thirty-eight patients with embolic stroke of undetermined source fulfilling inclusion criteria were identified. The crude prevalence of atrial fibrillation at the end of observation period was of 45.7%. Incidence rates at 6, 12, 18, 24, and 36 months resulted, respectively, 31.8% (95% CI, 30.4–46.7), 38.0% (95% CI, 30.4–46.9), 42.6% (95% CI, 34.5–51.6), 46.6% (95% CI, 38.2–55.8), and 50.4% (95% CI, 41.6–59.9). On multivariate analysis, only excessive supraventricular electric activity and left atrial enlargement resulted to be significant predictors of atrial fibrillation (p = 0.037 and p < 0.0001, respectively).

Conclusions

Atrial fibrillation may be detected in a relevant proportion (up to 50%) of patients with embolic stroke of undetermined source if a careful and extensive diagnostic work-up is employed. Excessive supraventricular electric activity and left atrial enlargement are significant predictors of the occurrence of atrial fibrillation in these patients.

中文翻译：

---

不明来源栓塞性卒中患者房颤的患病率和预测因素：一项真实的单中心回顾性研究

介绍

尽管进行了广泛的调查，但仍有多达三分之一的缺血性中风仍然是隐源性的。在很大比例的不明来源栓塞性卒中患者中可能会检测到心房颤动，特别是在临床实践中引入植入式环路记录仪之后。

方法

我们回顾性纳入了 2013 年 11 月至 2018 年 12 月期间转诊至我们单位的所有不明来源栓塞性卒中患者，其中在卒中事件发生后 6 个月内放置了植入式环路记录器。研究了房颤的患病率和预测因素。

结果

确定了 138 名满足纳入标准的不明来源栓塞性卒中患者。观察期结束时房颤的粗患病率为45.7%。6、12、18、24 和 36 个月的发生率分别为 31.8%（95% CI，30.4-46.7）、38.0%（95% CI，30.4-46.9）、42.6%（95% CI，34.5） –51.6)、46.6%（95% CI，38.2–55.8）和 50.4%（95% CI，41.6–59.9）。在多变量分析中，只有过度的室上电活动和左心房扩大是心房颤动的重要预测因子（分别为p  = 0.037 和p  < 0.0001）。

结论

如果采用仔细和广泛的诊断检查，可能会在相关比例（高达 50%）的不明来源栓塞性卒中患者中检测到心房颤动。过度的室上电活动和左心房扩大是这些患者发生心房颤动的重要预测因素。