Long-term recurrences and mortality in patients with noncardiac syncope.

INTRODUCTION AND OBJECTIVES: There are no in-depth studies of the long-term outcome of patients with syncope after exclusion of cardiac etiology. We therefore analyzed the long-term outcome of this population. METHODS: For 147 months, we included all patients with syncope referred to our syncope unit after exclusion of a cardiac cause. RESULTS: We included 589 consecutive patients. There were 313 (53.1%) women, and the median age was 52 [34-66] years. Of these, 405 (68.8%) were diagnosed with vasovagal syncope (VVS), 65 (11%) with orthostatic hypotension syncope (OHS), and 119 (20.2%) with syncope of unknown etiology (SUE). During a median follow-up of 52 [28-89] months, 220 (37.4%) had recurrences (21.7% ≥ 2 recurrences), and 39 died (6.6%). Syncope recurred in 41% of patients with VVS, 35.4% with OHS, and 25.2% with SUE (P=.006). In the Cox multivariate analysis, recurrence was correlated with age (P=.002), female sex (P <.0001), and the number of previous episodes (< 5 vs ≥ 5; P <.0001). Death occurred in 15 (3.5%) patients with VVS, 11 (16.9%) with OHS, and 13 (10.9%) with SUE (P=.001). In the multivariate analysis, death was associated with age (P=.0001), diabetes (P=.007), and diagnosis of OHS (P=.026) and SUE (P=.020). CONCLUSIONS: In patients with noncardiac syncope, the recurrence rate after 52 months of follow-up was 37.4% and mortality was 6.6% per year. Recurrence was higher in patients with a neuromedial profile and mortality was higher in patients with a nonneuromedial profile.

Head-up tilt test diagnostic yield in syncope diagnosis.

BACKGROUND: The European Syncope Guidelines (ESG) recommend the use of Head-up tilt test (HUT) in case of suspicion of vasovagal syncope (VVS) or orthostatic hypotensive syncope (OHS) after an adequate initial inconclusive evaluation. We report a single center experience in the scenario of suspected VVS or OHS, who underwent HUT in patients referred to a Syncope Clinic after ruling out high-risk causes. METHODS: We prospectively and consecutively included all syncopal patients that were referred for HUT, by their attending physician after performing a series of diagnostic tests to rule out cardiac etiology. The clinical history and diagnostic tests performed were reviewed prior to HUT. Patients were pre-classified according to the recommendations from the ESG as; VVS, OHS or Syncope of Unknown Etiology (SUE). RESULTS: We studied 1058 patients, 558 (52.7%) males, mean age 46.5 ±â€¯20.1 yr. There were no gender differences in age, risk factors, previous heart diseases, ECG findings or number of previous tests. Based on the ESG criteria a significant number of diagnostic tests were probably unnecessarily performed. HUT was positive in 609 patients (57.5%). The rate of positive HUT according to pre-classification was significantly different among groups: 60% VVS, 46.1% OHS and 54.3% SUE (p = 0.037). Combining ESG recommendations and HUT results of the 1058 resulted in 762 (72%) diagnosed as VVS, 89 (8.4%) as OHS and 207 (19.5%) as SUE. CONCLUSIONS: Appropriate application of ESG recommendations combined with HUT, identified 81% of patients with non-cardiogenic syncope, potentially avoiding a significant number of unnecessary diagnostic tests.