April 1, 2010Open Access
Long‐Term Follow‐Up of Patients with Syncope Evaluated by Head‐Up Tilt Test
Structured PICO
Does a positive head-up tilt test predict long-term recurrence of syncope in patients evaluated for unexplained syncope?
P
Population
107 patients (mean age 51 +/- 20 years) receiving head-up tilt test (HUTT) for diagnostic evaluation of unexplained/suspected neurocardiogenic syncope
I
Intervention
Positive head-up tilt test (HUTT)
C
Comparator
Negative head-up tilt test (HUTT)
O
Outcome
Long-term recurrence of syncope
A positive head-up tilt test does not predict long-term syncope recurrence, whereas a history of frequent recent syncopes (>4 in the past 12 months) is a strong independent predictor.
Abstract
BACKGROUND: Clinicians may be tempted to consider a positive head-up tilt test (HUTT) an unfavorable prognostic indicator. We investigated whether results of routine HUTT predict long-term recurrence of syncope. METHODS: We analyzed syncope recurrence at long-term among 107 patients (mean age 51 +/- 20 years) receiving HUTT for diagnostic evaluation of unexplained/suspected neurocardiogenic syncope in our Institute. RESULTS: HUTT was positive in 76 patients (vasodepressive response, n = 58; cardioinhibitory, n = 5; mixed, n = 13). During a median follow-up of 113 months (range, 7-161), 34 (32%) patients experienced recurrence (24 32% with positive HUTT during 110 months (7-159); 10 32% with negative HUTT during 120 22-161 months). Actuarial freedom from recurrence at 10 years did not significantly differ for patients with positive/negative test results (after passive/active phases) or with different positive response patterns (vasodepressive, cardioinhibitory, mixed). By contrast, history of >4 syncopes in the 12 months preceding HUTT stratified risk of recurrence, irrespective of HUTT positivity/negativity. At Cox proportional hazards analysis, history of >4 syncopes in the 12 months preceding HUTT was the single independent risk factor for recurrence both in the overall study population (HR, 1.7; 95% CI, 1.07-2.69) and within the subset of patients who tested positive (HR, 1.83; 95% CI, 1.07-3.17). CONCLUSIONS: This long-term follow-up study reinforces the concept that a positive HUTT should not be considered an unfavorable prognostic indicator; frequency of recent occurrences may be a more valid predictor.