Emergency Medicine Journal 2024

Original research

Diagnosis of Acute Aortic Syndrome in the Emergency Department (DAShED) study: an observational cohort study of people attending the emergency department with symptoms consistent with acute aortic syndrome Rachel McLatchie‍ ‍, 1 Matthew J Reed‍ ‍, 1,2 Nicola Freeman, 1 Richard A Parker, 3 Sarah Wilson‍ ‍, 4 Steve Goodacre‍ ‍, 5 Alicia Cowan, 6 Jessica Boyle, 7 Benjamin Clarke, 1 Ellise Clarke, 1 on behalf of the DAShED investigators

ABSTRACT Background The diagnosis of acute aortic syndrome (AAS) is commonly delayed or missed in the ED. We describe characteristics of ED attendances with symptoms potentially associated with AAS, diagnostic performance of clinical decision tools (CDTs) and physicians and yield of CT aorta angiogram (CTA). Methods This was a multicentre observational cohort study of adults attending 27 UK EDs between 26 September 2022 and 30 November 2022, with potential AAS symptoms: chest, back or abdominal pain, syncope or symptoms related to malperfusion. Patients were preferably identified prospectively, but retrospective recruitment was also permitted. Anonymised, routinely collected patient data including components of CDTs, was abstracted. Clinicians treating prospectively identified patients were asked to record their perceived likelihood of AAS, prior to any confirmatory testing. Reference standard was radiological or operative confirmation of AAS. 30-day electronic patient record follow-up evaluated whether a subsequent diagnosis of AAS had been made and mortality. Results 5548 patients presented, with a median age of 55 years (IQR 37–72; n=5539). 14 (0.3%; n=5353) had confirmed AAS. 10/1046 (1.0%) patients in whom the ED clinician thought AAS was possible had AAS. 5/147 (3.4%) patients in whom AAS was considered the most likely diagnosis had AAS. 2/3319 (0.06%) patients in whom AAS was considered not possible did have AAS. 540 (10%; n=5446) patients underwent CT, of which 407 were CTA (7%). 30-day follow-up did not reveal any missed AAS diagnoses. AUROC (area under the receiver operating characteristic) curve for ED clinician AAS likelihood rating was 0.958 (95% CI 0.933 to 0.983, n=4006) and for individual CDTs were: Aortic Dissection Detection Risk Score (ADD-RS) 0.674 (95% CI 0.508 to 0.839, n=4989), AORTAs 0.689 (95% CI 0.527 to 0.852, n=5132), Canadian 0.818 (95% CI 0.686 to 0.951, n=5180) and Sheffield 0.628 (95% CI 0.467 to 0.788, n=5092). Conclusion Only 0.3% of patients presenting with potential AAS symptoms had AAS but 7% underwent CTA. CDTs incorporating clinician gestalt appear to be most promising, but further prospective work is needed,

Handling editor Richard Body ► Additional supplemental material is published online only. To view, please visit the journal online (http://dx.doi. org/1 0.1136/e mermed-2023- 213266). For numbered affiliations see end of article. Correspondence to Professor Matthew J Reed, Emergency Medicine Research Group Edinburgh (EMERGE), Royal Infirmary of Edinburgh, Edinburgh, EH16 4SA, UK; m attreed@ed.a c.uk Received 3 April 2023 Accepted 30 September 2023 Published Online First 9 November 2023

INTRODUCTION Acute aortic syndrome (AAS) could be consid- ered as a wolf in sheep’s clothing in our emer- gency departments (EDs). AAS incorporates aortic dissection (AD), intramural haematoma (IMH) and penetrating aortic ulcer (PAU) and has a ‘lethal triad’; it is rare, has high mortality, and presents in atypical ways. 1 AAS affects approximately 4000 people in the UK per annum, 2 many not receiving timely diagnosis and treatment, and is responsible for 43 000–47 000 deaths annually in the USA. 3 HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY ⇒ We illustrate the diagnostic challenge of AAS and the limitations of methods for selecting patients for CT. The best decision aid to facilitate decision to CT and to outperform ED clinician gestalt is not yet clear. More research is required in truly undifferentiated ED populations such as these. WHAT IS ALREADY KNOWN ON THIS TOPIC ⇒ ED diagnosis of acute aortic syndrome (AAS) is a substantial challenge and many patients do not receive timely diagnosis and treatment. Over-investigation with too low a threshold for CT scanning of the thoracic aorta cannot be the solution. There is little research in truly undifferentiated ED populations, or in non- North American populations with different thresholds for CT and most previous studies of AAS clinical decision tools have limited inclusion to those patients undergoing CT aorta angiogram. WHAT THIS STUDY ADDS ⇒ In this multicentre observational study including 5548 patients with symptoms potentially attributable to AAS , 0.3% of patients presenting with potential AAS symptoms did have AAS and 10% of patients with potential AAS symptoms undergo CT. A third of proven patients with AAS still endure a diagnostic delay over 24 hours from time of arrival.

► http://d x.d oi.o rg/1 0.1 136/ emermed-2 023-213727

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including evaluation of the role of D-dimer. Trial registration number NCT05582967; NCT05582967.

To cite: McLatchie R, Reed MJ, Freeman N, et al . Emerg Med J 2024; 41 :136–144.

McLatchie R, et al . Emerg Med J 2024; 41 :136–144. doi:10.1136/emermed-2023-213266

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