Aim: To establish whether D-dimer is an independent predictor of 1-month serious outcome and all-cause death in syncope patients presenting to the emergency department (ED).
Methods: This was a prospective cohort study of all adults presenting with syncope to an ED in the UK. Plasma D-dimer concentrations were determined in citrated plasma obtained at presentation. The primary endpoint was the combination of serious outcome and all-cause death at 1 month.
Results: Of 237 patients enrolled, 205 patients had a suitable plasma sample and had complete follow-up. Seventeen patients had a serious outcome or death at 1 month including three patients with a pulmonary embolus and eight with a serious cardiovascular outcome. Nearly a half of all patients (n=94; 46%) had a plasma D-dimer concentration above the upper limit of normal, 10 of whom had a serious outcome or death at 1 month. Receiver-operator characteristic curve analysis showed no relationship between plasma D-dimer concentration and serious outcome or death at 1 month. An elevated plasma D-dimer concentration was found in all patients with a pulmonary embolus.
Conclusion: Plasma D-dimer is frequently raised in patients presenting with syncope to the ED and consequently does not predict 1-month serious outcome or death. We conclude that there is no role for the routine measurement of D-dimer in the management of patients presenting to the ED with syncope.