title: J-Wave in Patients With Syncope.
abstract: BACKGROUND
  Syncope is a common occurrence. The presence of J-wave, also known as early repolarization, on electrocardiogram is often seen in the general population, but the relationship between syncope and J-wave is unclear.
  
  
  RESULTS
  After excluding 67 patients with structural heart disease from 326 with syncope, we classified 259 patients according to the presence or absence of J-wave (≥1 mm) in at least 2 inferior or lateral leads. Head-up tilt test (HUT) was performed for 30 min. If no syncope or presyncope occurred, HUT was repeated after drug loading. Before tilt, 97/259 (37%) had J-wave (57 male, 47.6±22.5 years) and 162 patients had no remarkable change (89 male, 51.1±21.2 years). HUT-positive rate was higher in patients with J-wave, compared with patients without (P<0.0001). The combination of J-wave and descending/horizontal ST segment in the inferior leads was more strongly associated with positive HUT than J-wave with ascending ST segment (odds ratio, 3.23).
  
  
  CONCLUSIONS
  Prevalence of J-wave in the inferior or lateral leads was high in patients with syncope and was associated with HUT-induced neurally mediated reflex syncope (NMRS). Furthermore, the combination of J-wave and descending/horizontal ST segment in the inferior leads could be associated with a much higher risk of NMRS.
authors.affiliation: Division of Cardiology, Department of Medicine, Showa University.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Chiba
authors.forename: Yoshino
authors.initials: Y
authors.lastname: Minoura
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Onishi
authors.forename: Koichiro
authors.initials: K
authors.lastname: Inokuchi
authors.forename: Akinori
authors.initials: A
authors.lastname: Ochi
authors.forename: Shiro
authors.initials: S
authors.lastname: Kawasaki
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Onuma
authors.forename: Yumi
authors.initials: Y
authors.lastname: Munetsugu
authors.forename: Miwa
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ito
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Onuki
authors.forename: Norikazu
authors.initials: N
authors.lastname: Watanabe
authors.forename: Taro
authors.initials: T
authors.lastname: Adachi
authors.forename: Taku
authors.initials: T
authors.lastname: Asano
authors.forename: Kaoru
authors.initials: K
authors.lastname: Tanno
authors.forename: Youichi
authors.initials: Y
authors.lastname: Kobayashi
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013575:Syncope / Q000503:physiopathology*