Decision
Is there an alternative diagnosis?
Yes
- Acute aortic syndromes unlikely
No
- Perform D-dimer (Class I)
- Is D-Dimer positive?
Background
Risk Stratification
“High-risk examination features are hypertension, pulse deficits, systolic blood pressure differential, focal neurologic deficit with pain, murmur of aortic insufficiency with pain (bounding pulse, bibasilar crackles, elevated jugular venous pressure), or hypotension and shock. These features are included in the Aortic Dissection Detection Risk Score (ADD-RS).
The ADD-RS is a set of 12 clinical markers of aortic dissection (AoD) for low- to moderate-risk patients when AoD is in the differential diagnosis. The ADD-RS is based on the AHA and the American College of Cardiology (ACC) guidelines released in 2010, which were retrospectively validated using the IRAD data from 2011. In 2018, the authors of the ADvISED trial evaluated ADD-RS with the use of a D-dimer, through a multicenter prospective observational trial. They found an ADD-RS <1 and with a negative D-dimer demonstrated a negative likelihood ratio of 0.02, negative predictive value of 99.7, and a sensitivity of 98.8%. (In this study, a negative cutoff of 500 ng/mL was used.) An ADD-RS = 0 was found to have a sensitivity of 99.6%. Literature suggests that the application of this rule decreases unnecessary CT aortograms for suspected AoD. In 2019, chest x-ray was added to the clinical scoring tool, though it did not improve performance, and it illustrated insufficient sensitivity for ruling out the disease.
Although useful, the ADD-RS clinical tool has not been prospectively externally validated. Additionally, the tool incorporates the laboratory evaluation of D-dimer and should be used only to risk-stratify those who have a higher likelihood of AoD, as its accuracy as a “rule-out” tool is insufficient until further evaluation and validation occurs. Lastly, neither existing risk-stratification tools nor individual laboratory studies (such as a D-dimer) should be used alone in making clinic decisions.”