AIM To investigate the prognostic value of serum D-dimer levels in predicting in-hospital mortality in patients with acute type A aortic dissection (ATAAD) and acute type B aortic dissection (ATBAD).

METHODS A total of 349 patients diagnosed with acute aortic dissection at the Chest Pain Center of Guangxi Zhuang Autonomous Region People’s Hospital between January 2013 and December 2021 were included in this study. The optimal cutoff value of D-dimer was determined using X-tile software, which subsequently facilitated the stratification of patients into high and low D-dimer groups. Restrictive cubic spline (RCS) and Kaplan-Meier survival curves for different D-dimer levels were utilized to assess the predictive value of D-dimer in in-hospital mortality of ATAAD patients. Univariate COX regression analysis was performed to evaluate the relationship between different levels of D-dimer and patient outcomes. Significant variables were then included in a multivariate COX regression analysis to identify independent prognostic factors. A multivariate COX proportional hazards regression model was constructed and prognostic nomograms were developed. The predictive performance of the model was assessed by the area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS In ATAAD patients, compared with the D-dimer < 7.7 mg/L group, the D-dimer ≥ 7.7 mg/L group had a higher proportion of back pain, higher levels of urea and uric acid (all P<0.05), higher levels of white blood cells and neutrophils, higher in-hospital mortality rate (all P<0.01), and lower levels of platelets and lymphocytes (all P<0.01). In ATBAD patients, compared with the D-dimer < 2.4 mg/L group, the D-dimer ≥ 2.4 mg/L group had lower levels of hemoglobin and platelets (all P<0.05), higher proportion of pleural effusion, higher levels of urea, white blood cells, and neutrophils (all P<0.01), and lower levels of red blood cells and lymphocytes (P<0.01). ATAAD patients with high D-dimer levels had a higher in-hospital mortality rate (P<0.01), and there was no statistically significant difference in in-hospital mortality rate among ATBAD patients with different D-dimer levels. High levels of D-dimer (≥ 7.7 mg/L) (HR=3.40, 95% CI: 1.28~9.05), limb hypoperfusion upon admission (HR=9.23, 95% CI: 2.76~30.93), and alcohol consumption (HR=5.64, 95% CI: 1.91~16.67) are independent risk factors for in-hospital mortality in ATAAD patients. The AUC evaluation model predicts in-hospital mortality in ATAAD patients, with AUC values of 0.809 (95% CI: 0.740~0.878) and 0.793 (95% CI: 0.731~0.855) at 14 and 30 days, respectively.

CONCLUSION An elevation in D-dimer levels is significantly associated with increased in-hospital mortality in patients with acute aortic dissection, particularly in ATAAD patients where a D-dimer level ≥7.7mg/L can be considered as an independent risk factor for in-hospital mortality. These findings provide a crucial marker for risk assessment in the clinical management of acute aortic dissection patients.