The DAShED (Diagnosis of Aortic Syndrome in the ED) Study

NCT ID: NCT05582967

Last Updated: 2023-03-23

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 5548 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2022-09-26
• Study Completion Date: 2023-01-21

Brief Summary

Acute aortic syndrome (AAS) is a life-threatening emergency condition affecting the upper aorta affecting ~4000 people in the (United Kingdom; UK) a year with an ED misdiagnosis rate as high as 38%. Previous research has identified several strategies combining clinical probability scoring with blood tests (D-Dimer) to rule out the condition but when applied to a large population (ED) with relatively low numbers of actual cases, these result in a high rate of computed tomographic angiography (CTA) scanning. Current guidelines reflect the uncertainty of existing evidence.

This study, the first phase of three, aims to describe the characteristics of ED attendances with possible AAS, to determine the service implications of using different diagnostic strategies and inform future research. The investigators plan to recruit all ED attendances with possible AAS over a 1-4 week period. The investigators plan a prospective and retrospective approach to data collection adopting a waived-consent strategy with endpoint measures describing the characteristics of patients presenting with possible AAS.

Detailed Description

AAS is a life-threatening emergency condition which presents to the ED. Around 4,000 people suffer per year in the UK [1], many not receiving timely diagnosis and treatment. 25% of patients are not diagnosed until 24 hours after arriving in the ED due to the varied nature of presentation [2]. Chest pain is the most common presenting symptom of AAS (80%) although back pain (40%) and abdominal pain are not uncommon [1]. These symptoms account for over 2 million ED attendances per year in England [National Health Service; NHS Digital A&E 2021] and are overwhelmingly due to causes other than AAS. The estimated incidence of AAS is 1 in every 980 ED attendances with atraumatic chest pain [3], thus creating a substantial diagnostic challenge.

Prognosis is best when patients are treated early, and mortality increases 2% per hour of delay. [4] The misdiagnosis rate during the initial ED visit for AAS is estimated to be between 1 in 3 to 1 in 7 AASs [5], leading to worse outcomes [6,7] whilst CTA over testing leads to diagnostic yields as low as 2-3%. [2,8]. CTA scanning of the aorta has high sensitivity and specificity for diagnosing AAS, but an unrestricted CT strategy will incur significant costs, has ionising radiation risks, resource implications, CT delays for non-AAS patients and the burden of 'incidentalomas'.

Clinicians therefore need to use CTA selectively but there is no validated scoring system to help this decision. Several have been proposed [1, 9-14] including the ADD-RS score, the Canadian clinical practice guideline Clinical Decision Aid [13], the AORTAs score [14] and the Sheffield score [unpublished]. D-Dimer has been suggested as a rule-out biomarker in low pre-test probability patients (95-98% sensitivity) [15,16] and has been incorporated into the Aortic Dissection Detection-Risk Stratification (ADD-RS) score to reduce CTA rate in low pre-test probability patients. None have been studied in truly undifferentiated ED populations, or in the UK where CTA threshold is different compared to North America. It is currently unclear whether any have sufficient sensitivity to be acceptable to clinicians, which is the most accurate, and whether they are likely to lead to CTA and D-Dimer over testing. Assessment of CTA rate and CT positivity has also not previously been studied. The Royal College of Emergency Medicine has recently released a national guideline advocating any patient with an ADD-RS score of >=1 (no D-dimer incorporated) should have a CT aorta performed (unless other cause for symptoms identified and evidenced). The recommendation is not based on UK-validated clinical evidence, however, and clinical impacts of the recommendation are yet to be seen.

In view of these diagnostic challenges, the investigators aim in our programme of work to ultimately to assess which of the four aforementioned clinical decision tools is most effective, assess external validity, and assess clinical impact. This study (Phase 1; DAShED) will involve prospective data collection on all characteristics of four different risk scores, in addition to evaluation of patient characteristics, potential CT aorta rates with different strategies, and enrolment rates at participating sites. This will inform Phase 2, which will involve full interventional external validation study of the decision aid(s) selected in Phase 1 (including biomarker collection); the main objective being to select the score to subject to assessment of clinical impact (intervention step-wedge trial) in Phase 3.

This is an observational cohort study of all people attending the ED with symptoms of possible AAS, including new-onset chest, back or abdominal pain, syncope or symptoms related to malperfusion.

Conditions

Aortic Dissection

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Interventions

Completion of focused Electronic Case Report Form

All patients will have a focussed Electronic Case Report Form completed collecting information around Presenting complaint, Past Medical History, Family History, Physical Examination findings, and Investigations.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• People attending the ED with symptoms of AAS, including those with new-onset chest, back or abdominal pain, syncope or symptoms related to malperfusion.
• ≥16 years old

Exclusion Criteria

• No symptoms of AAS.
• <16 years old

• Minimum Eligible Age: 16 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Edinburgh

OTHER

Sponsor Role: collaborator

NHS Lothian

OTHER_GOV

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Rachel McLatchie

Role: PRINCIPAL_INVESTIGATOR

Accord Clinical Research

Locations

Royal United Hospital

Bath, , United Kingdom

Bristol Royal Infirmary

Bristol, , United Kingdom

North Bristol NHS Trust

Bristol, , United Kingdom

Addenbrookes hospital

Cambridge, , United Kingdom

Royal Infirmary of Edinburgh

Edinburgh, , United Kingdom

St Johns Hospital

Edinburgh, , United Kingdom

Frimley Health

Frimley, , United Kingdom

Queen Elizabeth University Hospital

Glasgow, , United Kingdom

Royal Alexandra Hospital

Glasgow, , United Kingdom

James Paget University Hospital

Great Yarmouth, , United Kingdom

Harrogate

Harrogate, , United Kingdom

Raigmore

Inverness, , United Kingdom

Queen Elizabeth Hospital NHS Foundation Trust

Kings Lynn, , United Kingdom

Victoria Hospital

Kirkcaldy, , United Kingdom

Lewisham and Greenwich NHS Trust

Lewisham, , United Kingdom

Luton & Dunstable University Hospital

Luton, , United Kingdom

Wythenshawe Hospital

Manchester, , United Kingdom

Milton Keynes Universoty Hospital NHS Foundation Trust

Milton Keynes, , United Kingdom

Royal Victoria Infirmary

Newcastle, , United Kingdom

Royal Oldham Hospital

Oldham, , United Kingdom

John Radcliffe Hospital

Oxford, , United Kingdom

Royal Glamorgan Hospital

Pont-y-clun, , United Kingdom

Royal Berkshire NHS Foundation Trust

Reading, , United Kingdom

Sheffield Teaching Hospitals NHS Foundation Trust

Sheffield, , United Kingdom

Wexham Park

Slough, , United Kingdom

Countries

United Kingdom

References

McLatchie R, Reed MJ, Freeman N, Parker RA, Wilson S, Goodacre S, Cowan A, Boyle J, Clarke B, Clarke E; DAShED investigators. 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. Emerg Med J. 2024 Feb 20;41(3):136-144. doi: 10.1136/emermed-2023-213266.

Reference Type: DERIVED

PMID: 37945311 (View on PubMed)

Related Links

http://www.emergeresearch.org/trial/dashed/

Study website

Other Identifiers

22/PR/0807

Identifier Type: OTHER

Identifier Source: secondary_id

315948

Identifier Type: OTHER

Identifier Source: secondary_id

AC22083

Identifier Type: -

Identifier Source: org_study_id