Background: Transient loss of consciousness (TLOC) is a common clinical problem.
Objective: The aim of this study was to assess the yield and accuracy of the initial evaluation, consisting of standardized history, physical examination, and ECG performed by attending physicians in patients with TLOC.
Methods and results: Five hundred and three adult patients (mean age 53 +/- 19; 56% male) presenting with TLOC to the Academic Medical Center Amsterdam between February 2000 and May 2002 were included in this study. After initial evaluation, the physician made a certain, a highly likely (>80% certain), or no initial diagnosis. Initially undiagnosed patients received additional cardiological testing, additional history taking, and autonomic function tests. After 2 years of follow-up, an expert committee determined the final diagnoses. Two-year follow-up was obtained in 99% of the patients. The yield of certain diagnoses after the initial evaluation was 24%, increasing to 63% after including the highly likely diagnoses. The diagnostic accuracy of the initial certain diagnoses was 93% (95% CI 87-97%), decreasing to 88% (95% CI 84-91%) after inclusion of the initial highly likely diagnoses.
Conclusion: Attending physicians can make a diagnosis based on initial evaluation in 63% of patients with TLOC, with an overall diagnostic accuracy of 88%. The use of additional testing, beyond history, physical examination, and ECG can be avoided in many patients with TLOC.