ADvISED Study of D-Dimer with Aortic Dissection Detection Risk Score (ADD-RS)
The Article: Nazerian P et al, “Diagnostic Accuracy of the Aortic Dissection Detection Risk Score Plus D-Dimer for Acute Aortic Syndromes: The ADvISED Prospective Multicenter Study.” Circulation. 2018 Jan 16;137(3):250-258. PubMed Full-text at Journal Site
The Study: D-dimer has long been suspect to have substantial though imperfect sensitivity to detect aortic dissection (and acute aortic syndromes more broadly). This study prospectively assessed the sensitivity D-dimer testing in combination with the aortic dissection detection risk score (ADD-RS), which was previously found to be 96% sensitive on the large IRAD registry from which it was developed (Rogers AM et al, “Sensitivity of the aortic dissection detection risk score, a novel guideline-based tool for identification of acute aortic dissection at initial presentation: results from the international registry of acute aortic dissection.” Circulation. 2011 May 24;123(20):2213-8. PubMed Full-text at Journal Site).
Patients with a D-dimer < 500 and no more than one high-risk comorbidity, complaint, or exam finding (see list below of the Risk Factors which make up the ADD-RS tool) were considered to have been “ruled out.” Consecutive patients were recruited from 6 hospitals (mostly in Italy), and had both acute aortic syndrome in the primary clinician’s differential diagnosis and chest/abdominal/back pain, syncope, or perfusion deficit.
ADD-RS Components: Conditions: recent aortic manipulation, known aortic valve disease or thoracic aneurysm, Marfan syndrome, family history of aortic syndrome Complaints: chest/back/abdominal pain described as abrupt, severe, ripping, or tearing Exam findings: new aortic regurgitation murmur or focal neurologic deficit (only if pain), pulse or systolic pressure differential, hypotension or shock
The Results: Of the 1850 patients included, 241 had some sort of acute aortic syndrome. The overall sensitivity of the ADD-RS score with a D-dimer < 500 was 99.8%, with a lower 95% confidence interval of 99%. 1 of the 22 patients with a D-dimer < 500 but more than 1 risk factor had an acute aortic syndrome, and 8 patients total with D-dimer < 500 had an acute aortic syndrome. The single missed dissection patient with no risk factors had a widened mediastinum, and the other patients with negative D-dimers had fairly classic histories with sudden pain. The negative likelihood ratio of a D-dimer < 500 was 0.05 (95%CI 0.03-0.1). 806 patients never had conclusive diagnostic imaging, but all but 2 of these had 14-day clinical follow-up. The authors estimated that use of this tool could reduce aortic imaging for 3 out of 5 patients in this group.
The Takeaway: D-dimer may be helpful in ruling out acute aortic syndromes, but the data to support it’s use still lags behind established tools like PERC.