title: Usefulness and safety of shortened head-up tilt testing potentiated with sublingual glyceryl trinitrate in older patients with recurrent unexplained syncope.
abstract: OBJECTIVE
  To evaluate the sensitivity and tolerability of shortened, glyceryl trinitrate (GTN)-potentiated, head-up tilt test (HUT) in patients older and younger than 65 with unexplained syncope and to compare the specificity of GTN-potentiated HUT (GTN-HUT) in older and younger controls.
  
  
  METHODS
  Methodological study.
  
  
  METHODS
  Syncope units in secondary and tertiary hospitals.
  
  
  METHODS
  Three hundred twenty-four consecutive patients with unexplained syncope (100 aged > or =65 (mean age +/- standard deviation 73 +/- 6; 35 men) and 224 aged <65 (41 +/- 15; 111 men)) and 64 controls (29 aged > or =65 (73 +/- 6; 13 men) and 35 aged <65 (42 +/- 13; 16 men)).
  
  
  METHODS
  Patients and controls were tilted upright to 60 degrees for 20 minutes. If syncope did not occur, sublingual GTN (400 microg) was administered and 60 degrees HUT was continued for 15 minutes. Responses were classified as positive, negative, or exaggerated (slow decrease in blood pressure with a slight decrease in heart rate after GTN).
  
  
  METHODS
  Electrocardiogram and arterial pressure were monitored continuously.
  
  
  RESULTS
  GTN-HUT was positive in 60% and 66% (NS), negative in 29% and 33% (NS), and exaggerated in 11% and 1% (P <.001) of older and younger patients, respectively. In older and younger controls, the GTN-HUT was negative in 70% and 86% and exaggerated in 28% and 9% of cases, respectively, (P <.05). The overall specificity (considering as negative also the exaggerated responses) was 97% in older and 94% in younger subjects. No patient or control experienced serious side effects.
  
  
  CONCLUSIONS
  The shortened GTN-HUT provides satisfactory positivity rate and specificity in older patients. This test may be considered as a diagnostic tool in assessing recurrent unexplained syncope in older patients.
authors.affiliation: Division of Cardiology, Ospedale San Pietro Igneo, Fucecchio, Florence, Italy.
authors.forename: Attilio
authors.initials: A
authors.lastname: Del Rosso
authors.forename: Andrea
authors.initials: A
authors.lastname: Ungar
authors.forename: Paolo
authors.initials: P
authors.lastname: Bartoli
authors.forename: Tommaso
authors.initials: T
authors.lastname: Cellai
authors.forename: Chiara
authors.initials: C
authors.lastname: Mussi
authors.forename: Niccolò
authors.initials: N
authors.lastname: Marchionni
authors.forename: Giulio
authors.initials: G
authors.lastname: Masotti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D004562:Electrocardiography; D005260:Female; D006257:Head / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin; D012008:Recurrence; D012680:Sensitivity and Specificity; D013575:Syncope / Q000175:diagnosis*; D018667:Tilt-Table Test / Q000379:methods*
chemical_list: D005996:Nitroglycerin