Objectives: In patients at low clinical probability of acute aortic syndromes (AASs), decision on advanced aortic imaging is cumbersome. Integration of the aortic dissection detection risk score (ADD-RS) with D-dimer (DD) provides a potential pipeline for standardized diagnostic rule-out. We systematically reviewed and summarized supporting data.
Methods: Cross-sectional studies assessing integration of ADD-RS with DD for diagnosis of AASs were identified on MEDLINE, EMBASE and Web Of Science databases. Two reviewers independently screened articles, assessed quality, and extracted data. The quality of design and reporting was evaluated with the QUADAS-2 and STARD tools. Individual patient data were obtained, to allow analysis of both conventional (500 ng/mL) and age-adjusted (DDage-adj ) DD cutoffs. Data were summarized for four diagnostic strategies combining ADD-RS = 0 or ≤ 1, with DD < 500 ng/mL or < DDage-adj . The statistical heterogeneity of the diagnostic variables was estimated with Higgins' I2 . Pooled values were calculated for variables showing nonsignificant heterogeneity.
Results: After screening of 680 studies, four articles (including a total of 3,804 patients) met inclusion criteria. One prospective study provided a low risk of bias/applicability concerns, while methodologic limitations were found in the other three retrospective studies. Statistical heterogeneity was negligible for sensitivity and negative likelihood ratio (LR) values and significant for specificity and positive LR values of all diagnostic strategies. Pooled sensitivity was 99.9% (95% confidence interval [CI] = 99.3% to 100%, I2 = 0) for ADD-RS = 0 and DD < 500 ng/mL or < DDage-adj , 98.9% (95% CI = 97.9% to 99.9%, I2 = 0) for ADD-RS ≤ 1 and DD < 500 ng/mL, and 97.6% (95% CI = 96.3% to 98.9%, I2 = 0) for ADD-RS ≤ 1 and DD < DDage-adj .
Conclusions: Despite methodologic limitations, integration of ADD-RS = 0 or ≤ 1 with DD < 500 ng/mL shows negligible heterogeneity and consistently high sensitivity across studies, thus supporting reliability for diagnostic rule-out of AASs. Data supporting ADD-RS = 0 plus DDage-adj appear preliminary and require further scrutiny.
© 2020 by the Society for Academic Emergency Medicine.