The point-of-care D-dimer test provides a fast and accurate differential diagnosis of Stanford Type A aortic syndrome and ST-elevated myocardial infarction in emergencies

Abstract Background: The research of the sensitivity and specificity point-of-care testing (POCT) of D-dimer as a diagnostic protocol for differential diagnosis of TAAS (hereafter as TAAS) mimicking ST-elevated myocardial infarction (STEMI) with regular STEMI in the emergency department is limited.Methods: Full medical information of 32 patients confirmed TAAS and 527 patients confirmed STEMI from January 1st, 2016 to October 1st, 2021 were retrospectively analyzed in Shanghai tenth People’s Hospital of Tongji University.Results: The baseline characteristics of two groups of patients were well-balanced post propensity score matching (PSM) analysis, and each group had 32 patients enrolled. Patients in the STEMI group had higher positive cardiac troponin I (cTNI) (0.174ng/mL vs. 0.055ng/mL, P=0.008) results but lower D-dimer (0.365ug/mL vs. 31.50ug/mL, P<0.001) results than the TAAS group. The AUC values were 0.998 (95% CI:0.993-1.000) for the D-dimer, and the D-dimer cutoff value of 2.155ug/mL had the best sensitivity of 100% and specificity of 96.9% in the TAAS group. No significant correlation between the D-dimer concentration and the time from symptom onset to first medical contact in both groups (TAAS group: r=-0.248, P=0.170; STEMI group: r=-0.159, P=0.383). The total in-hospital mortality for the patients with TAAS presenting as STEMI was 62.5% (20/32). The mortality rate for TAAS patients confirmed by CTA was significantly lower (40% vs. 82.4%, P=0.014) than the mortality rate for TAAS patients confirmed by CAG and had a longer average survival time (log-rank=0.015) but less peri-surgical complications, especially gastrointestinal hemorrhage (0.00% vs. 55.6%, P<0.001). CTA diagnosis can reduce the mortality rate by 67.5% (95%CI:0.124-0.850, P=0.16).Conclusions: The POCT D-dimer can exclude TAAS mimicking STEMI from regular STEMI prior to reperfusion therapy.