Accuracy of a diagnostic strategy combining aortic dissection detection risk score and D-dimer levels in patients with suspected acute aortic syndrome

Aims: The European Society of Cardiology recently proposed a novel diagnostic algorithm combining the aortic dissection detection (ADD) risk score with D-dimer level assessment for detecting acute aortic syndromes (AASs) in patients presenting with chest pain. The diagnostic accuracy of this strategy is yet to be validated. Methods: We retrospectively identified 376 patients with chest pain and available D-dimer on admission to the emergency department of our institution between January 2011 and May 2014. The ADD risk score was calculated using retrospective blinded chart review. A score ⩽1 was defined as ‘low probability’, whereas a score >1 as ‘high probability’. AASs were diagnosed in 85 (22.6%) patients. Results: Patients with AAS more frequently had a ‘high probability’ score than AAS-negative patients (63.5% vs 1.0%; P<0.001). An ADD risk score ⩾1 had a sensitivity of 98.8% and a specificity of 64.6% for diagnosing AAS with a failure rate of 0.5%, whereas an ADD risk score ⩾2 had a sensitivity of 63.5% and a specificity of 98.9% with a failure rate of 9.7%. Among the patients with a ‘low probability’ score, D-dimer had a sensitivity and specificity for the detection of AAS, respectively, of 93.5% and 63.2%, with a negative predictive value of 98.9% and a failure rate of 1.1%. Conclusions: A ‘high probability’ ADD score detected AAS with good specificity. A ‘low probability’ score combined with negative D-dimer safely and efficiently ruled out AAS with a low failure rate.