Analysis of Temporal and Causal Relationship Between Syncope and 30-Day Events in a Cohort of Emergency Department Patients to Identify the True Rate of Short-term Outcomes.

Background: There are a limited number of studies on the short-term prognosis of syncopal patients, and those available are heterogeneous and often have considered events without a clear relationship with the syncopal episode as serious outcomes.

Objective: The aim of this study was to identify the incidence of short-term true outcomes of a syncopal episode, only considering those occurring after a reasonable period of time, with a plausible causal relationship with index syncope as well as syncopal recurrences causing major trauma.

Methods: In this retrospective, observational study, we assessed all patients managed in the emergency department (ED) during a 6-month period, with 30 days of follow-up.

Results: The study population consisted of 982 consecutive syncopal patients. We observed short-term serious events, in a broad sense, in 154 patients (15.7%), the most frequent being dysrhythmias (20.8%), cerebrovascular accidents (18.2%), major traumatic injuries (16.2%), death (13%), and myocardial infarction (9.7%). Most of these events (63.6%) could be identified within 72 h, mainly in the ED. Only 19 patients (2.2% of the sample), experienced a true short-term outcome (7 deaths, 1 myocardial infarction, 9 dysrhythmias, 1 major bleeding event, and 1 traumatic syncopal recurrence).

Conclusions: The incidence of short-term true outcomes of syncope is extremely low. Distinguishing true outcomes from other events has a crucial significance for understanding the real prognostic role of syncope and for planning ED management. Once patients with syncope as a direct consequence of an acute disease needing admission by itself are excluded, most patients with unexplained syncope could be safely discharged after primary evaluation and brief ED monitoring.