title: The effect of head-upright tilt table testing for vasovagal syncope on P-wave duration.
abstract: Fluid shifts in vasovagal syncope may be reflected in electrocardiographic P-wave duration. We examined the effect of head-upright tilt-table testing (HUT) on P-wave duration among patients with positive or negative HUT. P-wave duration was measured at baseline and several post-HUT time points. In patients with a positive HUT, the test was immediately discontinued. P-wave duration measurements obtained at the completion of the test or when symptoms occurred were compared to baseline measurements. The P-wave duration among patients with a positive HUT was significantly reduced at the onset of symptoms as compared to baseline (-14.0 ms, P = .0054) and 2-minute tilt measurements (-11.3 ms, P = .0246). P-wave duration measurements were not reduced in patients experiencing a negative HUT at any follow-up time. We showed a significant reduction in P-wave duration among patients experiencing positive HUT that suggests a dynamic relationship between atrial volume and P-wave duration.
authors.affiliation: Hartford Hospital Division of Cardiology and Drug Information Center, Hartford, CT 06102, USA.
authors.forename: Jawad
authors.initials: J
authors.lastname: Haider
authors.forename: James S
authors.initials: JS
authors.lastname: Kalus
authors.forename: C Michael
authors.initials: CM
authors.lastname: White
authors.forename: Dhiraj D
authors.initials: DD
authors.lastname: Narula
authors.forename: Danette C
authors.initials: DC
authors.lastname: Guertin
authors.forename: Michael F
authors.initials: MF
authors.lastname: Caron
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Kluger
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D019462:Syncope, Vasovagal / Q000175:diagnosis* / Q000473:pathology; D018667:Tilt-Table Test; D013997:Time Factors