title: Reproducibility of sequential head-up tilt testing in patients with recent syncope, normal ECG and no structural heart disease.
abstract: OBJECTIVE
  To assess the reproducibility of the response to sequential head-up tilt tests.
  
  
  RESULTS
  A head-up tilt test was performed early after syncope in 127 patients with a normal ECG and no structural heart disease. Patients with a positive response (82 patients) were randomized to two (1 week and 2 weeks later) or one (2 weeks later) additional head-up tilt tests, and patients with a negative response (45 patients) were randomized to a second head-up tilt test 1 or 2 weeks after the first. The reproducibility of a positive response in the second head-up tilt test was 80% after 1 week and 53% after 2 weeks (P<0.01). Only 53% of the patients with a positive response to a first and second head-up tilt test had a positive response to a third (P=0.01). Intra-individual variation in the time to a positive response was wide. The reproducibility of the cardioinhibitory responses was very poor. Reproducibility of a negative response was 80%.
  
  
  CONCLUSIONS
  In patients with recent syncope, the rate of positive responses decreases with sequential head-up tilt tests. Furthermore, the time to a positive response in different head-up tilt tests shows important intra-individual variations, and the reproducibility of the cardioinhibitory responses is very poor. In contrast, the reproducibility of the negative responses is high.
authors.affiliation: Servei de Cardiologia, Hospital Universitari Vall d'Hebrón, Barcelona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Sagristà-Sauleda
authors.forename: B
authors.initials: B
authors.lastname: Romero
authors.forename: G
authors.initials: G
authors.lastname: Permanyer-Miralda
authors.forename: A
authors.initials: A
authors.lastname: Moya
authors.forename: J
authors.initials: J
authors.lastname: Soler-Soler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013575:Syncope / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D018667:Tilt-Table Test