Dear Editor,

We have read with great interest the article published in your journal titled “Predictors of stroke or systemic embolism in patients with non-valvular atrial fibrillation with CHA₂DS₂-VASc score of 0” by Choi et al. (2023). The authors evaluated the predictors of atrial fibrillation in patients with CHA₂DS₂-VASc score of 0. We would like to draw attention to a few points about this article.

The major finding of the study was that risk of stroke or embolism rate was very low. Interestingly, the most of the patients were followed up without anticoagulation and no stroke was observed. We believe that especially the short follow-up period has shown a significantly lower risk of stroke in the study. On the other hand, it has been reported that atrial fibrillation (AF) is observed in 24% of all strokes and 12% in non-fatal strokes (Akyea et al., 2021; Tsao et al., 2022). Considering the retrospective nature of the study and the fact that two patients were even on anticoagulants, it may be difficult to say exactly how many of the patients who reached the primary outcome were guilty of AF.

Another point, the fact that patients with left ventricular end diastolic diameter of 46 mm and above were not evaluated in terms of heart failure with preserved ejection fraction (HFpEF) seems to be the limitation of the study. It is possible that the CHA₂DS₂-VASc score was calculated as 0 even though some patients had heart failure, ignoring the fact that the incidence of heart failure is approximately 1% especially under the age of 55, the lack of natriuretic peptide evaluation and the threshold for the resting E/e’ ratio is 9 in HFpEF diagnosis (McDonagh et al., 2021).

Finally, we would like to draw attention to obesity that is important in the development of AF and stroke and systemic embolism, as the mean weight was almost close to overweight range in the study. We also have seen that age is actually an important predictor in terms of shedding light on future studies on the prediction of outcomes.

亲爱的编辑，

我们非常感兴趣地阅读了Choi 等人在贵刊上发表的题为“CHA ₂ DS ₂ -VASc评分为 0 的非瓣膜性心房颤动患者中风或全身性栓塞的预测因子”的文章。（2023 年）。_{作者评估了 CHA 2} DS ₂ -VASc 评分为 0的患者房颤的预测因子。我们想提请注意本文的几个要点。

该研究的主要发现是中风或栓塞率的风险非常低。有趣的是，大多数患者在未接受抗凝治疗的情况下接受随访，未观察到卒中。我们认为，特别是较短的随访期已表明研究中中风的风险显着降低。另一方面，据报道，在 24% 的所有中风和 12% 的非致命性中风中观察到心房颤动 (AF)（Akyea 等人，2021 年；Tsao 等人，  2022年 ）。考虑到该研究的回顾性性质以及两名患者甚至服用抗凝剂的事实，可能很难准确地说出达到主要结果的患者中有多少人患有房颤。

另一点，左心室舒张末期直径为 46 mm 及以上的患者未根据射血分数保留的心力衰竭 (HFpEF) 进行评估，这似乎是该研究的局限性。有可能 CHA ₂ DS ₂ -VASc 评分被计算为 0，即使一些患者有心力衰竭，忽略心力衰竭的发生率约为 1%，尤其是 55 岁以下，缺乏利钠肽评估在 HFpEF 诊断中，静息 E/e' 比率的阈值为 9（McDonagh 等人，  2021 年）。

最后，我们想提请注意肥胖对 AF 和中风以及全身性栓塞的发展很重要，因为研究中的平均体重几乎接近超重范围。我们还看到，年龄实际上是一个重要的预测指标，可以阐明未来的结果预测研究。