- Syncope is a common clinical problem that often remains undiagnosed despite extensive and expensive diagnostic evaluation. To assess the diagnostic evaluation, costs and prognosis of patients hospitalized for syncope in a tertiary referral center according to discharge diagnosis. We retrospectively reviewed the medical records of patients with a diagnosis of syncope discharged from a tertiary referral center in 1999. In addition, mortality data were obtained retrospectively a year after discharge for each patient. The study group comprised 376 patients. Discharge etiologies were as follows: vasovagal 26.6%, cardiac 17.3%, neurological 4.3%, metabolic 0.5%, unexplained 47.3%, and other 4%. A total of 345 patients were admitted to the internal medicine department, 28 to the intensive cardiac care unit, and 3 to the neurology department. Cardiac and neurological tests were performed more often than other tests, with a higher yield in patients with cardiac and neurological etiologies respectively. The mean evaluation cost was 11,210 +/- 8133 NIS, and was higher in the ICCU than in internal medicine wards (19,210 +/- 11,855 vs. 10,443 +/- 7314 NIS, respectively; P = 0.0015). Mean in-hospital stay was 4.9 +/- 4.2 days, which was longer in the ICCU than in medicine wards (7.2 +/- 5.6 vs. 4.6 +/- 3.5 days, respectively; P = 0.024). Short-term mortality rates (30 days after discharge) and long-term mortality rates (1 year after discharge) were 1.9% and 8.8% respectively, and differed according to discharge etiology. LTM rates were significantly higher in patients discharged with cardiac, neurological and unknown etiologies (not for vasovagal), compared with the general population of Israel (1 year mortality rate for the age-adjusted [65 years] general population = 2.2%). The LTM rate was higher in patients discharged with a cardiac etiology than in those with a non-cardiac etiology (15.4% vs. 7.4%, P = 0.04). Higher short and long-term mortality rates were associated with higher evaluation costs. Hospitalization in a tertiary referral center for syncope is associated with increased mortality for most etiologies (except vasovagal), cardiac more than non-cardiac. Despite high costs of inpatient evaluation, associated with more diagnostic tests, longer in-hospital stay and higher mortality rates, nearly half of the patients were discharged undiagnosed. Outpatient evaluation should be considered when medically possible.