D-dimer levels remain elevated in acute aortic dissection after 24 h

D-dimer levels are elevated in patients with acute aortic dissection (AAD). Although D-dimer levels have been used to rule out AAD within 24 h of symptom onset, it is unknown whether they may be used reliably after 24 h but within the acute period. Here, we tested the hypothesis that D-dimer levels remain elevated in AAD patients for at least 10 d after dissection onset.

D-dimer levels were measured in preoperative heparinized plasma samples from 100 patients with confirmed AAD for up to 10 d after onset of dissection. When possible, serial samples were obtained for ≥2 d. D-dimer levels were measured in fibrinogen equivalent units using a BCS XP automated coagulation analyzer, which is approved for citrated samples. Therefore, we first validated our samples by comparing D-dimer levels in heparinized and citrated plasma samples from 29 individuals, including patients with and without aortic disease and healthy donors.

The correlation between heparinized and citrated plasma samples was 0.991 (P ≤ 0.001). At a threshold of 1.6 μg/mL, the overall sensitivity of the D-dimer assay in AAD patients up to 10 d after onset of dissection was 95.3%.

D-dimer levels remained elevated in AAD patients over a 10-d period after dissection onset and may be helpful in ruling out AAD in patients who seek treatment after the first 24 h but within the acute period. Heparinized plasma samples may be substituted for citrated samples when evaluating D-dimer levels using the BCS XP coagulation analyzer.