Hrev_master Emergency Care Journal 2023; volume 19: Dear Editor, We thank Vercelli et al.1 for their comments on our paper: Why do emergency department clinicians miss acute aortic syndrome? A case series and descriptive analysis. We fully agree with the authors, that investigating the heart and aorta using POCUS may allow for an earlier diagnosis and there- fore more expedient treatment of a patient with acute aortic syn- drome (AAS). We would also agree with the authors that POCUS is a point of care test with good specificity for the detection of AAS (i.e., it may be good at ruling in the diagnosis) but has poor sensi- tivity for the detection of AAS (i.e., it is not good at ruling out the diagnosis). Similar to other emergency conditions, POCUS also has a bias in that it is likely to be better at detecting AAS patients who exhibit the classic symptoms and signs of the condition, those who are sicker; and patients for whom the treating clinician has a high pre- test probability of AAS and who are unlikely to be discharged without definitive Computed Tomography Angiography of the aorta (CTA) imaging. It is those patients who do not exhibit the classic symptoms and signs of the condition, who may be less physiologically unwell and in whom the treating clinician has a lower pre-test probability of AAS who are more likely to be misdiagnosed or to suffer delayed diagnosis. These patients are also more likely to not have findings on POCUS. We also note that the use of POCUS to evaluate the heart and aorta is not routine in all emergency departments or countries. Whilst POCUS, where expertise to do this in a timely manner is available, is no doubt a great timely addition to the diagnostic work up, clinicians must ensure that they are not falsely reassured by a normal POCUS exam and should still consider CTA to definitely rule out the diagnosis where appropriate. References 1. Vercelli A, Berardi E, Poggiali E. Comments on “Why do emergency department clinicians miss acute aortic syndrome? A case series and descriptive analysis”. Emerg care J 2023;19:11433. 2. McLatchie R, Wilson S, Reed M, et al. Why do emergency department clinicians miss acute aortic syndrome? A case series and descriptive analysis. Emerg Care J 2023;19:11153. Emergency Care Journal 2023; volume 19:11470 [Emergency Care Journal 2023; 19:11470] [page 67] Authors’ response to Comments on “Why do emergency department clinicians miss acute aortic syndrome? A case series and descriptive analysis” Matthew J. Reed,1,2 Rachel McLatchie,1 Sarah Wilson,3 Francoise Ticehurst,3 Kathryn Easterford,1 Salma Alawiye,1 Alicia Cowan,1 Aakash Gupta1 1Emergency Medicine Research Group Edinburgh (EMERGE), Department of Emergency Medicine, Royal Infirmary of Edinburgh, Edinburgh; 2Acute Care Group, Usher Institute of Population Health Sciences and Informatics, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh; 3Emergency Department, Wexham Park Hospital, Frimley Health NHS Foundation Trust, Slough, UK Correspondence: Matthew J. Reed, Emergency Medicine Research Group Edinburgh (EMERGE), Department of Emergency Medicine, Royal Infirmary of Edinburgh, Edinburgh, UK. Tel.: +44(0)1312421284. E-mail: mattreed@ed.ac.uk Key words: aortic dissection; diagnostic accuracy; aorta; emer- gency; diagnosis. Contributions: MR and SW, wrote the manuscript. All the authors viewed the final version. Conflict of interest: the authors declare no potential conflict of inter- est, and all authors confirm accuracy. Availability of data and materials: all data generated or analyzed during this study are included in this published article. Ethics approval: the study was deemed to be a service evaluation and therefore ethical approval was not required. Informed consent: not applicable. Availability of data and materials: not applicable. Consent to participate: not applicable. Informed consent: not applicable. Funding: MR is supported by an NHS Research Scotland Career Researcher Clinician award. Received for publication: 15 May 2023. Accepted for publication: 16 May 2023. This work is licensed under a Creative Commons Attribution 4.0 License (by-nc 4.0). ©Copyright: the Author(s), 2023 Licensee PAGEPress, Italy Emergency Care Journal 2023; 19:11470 doi:10.4081/ecj.2023.11470 Publisher's note: all claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher. No n- co mm er cia l u se on ly