The application of a standardized strategy of evaluation in patients with syncope referred to three syncope units

The appropriate diagnostic work-up of patients with syncope is not well defined. We applied the guidelines of Italian 'Associazione Nazionale Medici Cardiologi Ospedalieri' to a group of consecutive patients with syncope referred to three Syncope Units. The aim of the study was to evaluate the applicability of those guidelines in the 'real world' and their impact on the use of the tests. We evaluated 308 consecutive patients with syncope (mean age 61 +/- 20 years; median of three syncopal episodes per patient). The hierarchy and appropriateness of diagnostic tests and the definitions of the final diagnosis followed standardized predefined criteria. In brief, all patients underwent initial evaluation consisting of history, physical examination, supine and upright blood pressure measurement and standard electrocardiogram (ECG) (only in patients > 45 years or with history of heart disease). Any subsequent investigations were based on the findings of the initial evaluation. Priority was given to cardiological tests (prolonged ECG monitoring, exercise test, electrophysiological study), or to neurally mediated tests (carotid sinus massage, tilt test, ATP test), or to neuro-psychiatric tests, as appropriate. The initial evaluation alone was diagnostic in 72 patients (23%). One further test was necessary for diagnosis in 65 patients (21%), > or = 2 tests in 64 (21%) and > or = 3 tests in 50 (16%). The diagnostic yield was 10% for ECG, 3% for echocardiogram, 16% for Holter, 5% for exercise test, 27% for electrophysiological study, 57% for carotid sinus massage, 52% for tilt testing and 15% for ATP test. At the end of the work-up the mechanism of syncope remained unexplained in 57 patients (18%). When standardized criteria based on the appropriateness of indications are used, few simple tests are usually needed for diagnosis of syncope.