title: Direct discrimination and full-day disclosure of ventricular parasystole on new heart rate tachograms.
abstract: BACKGROUND
  To discriminate ventricular parasystole from fixed coupling interval ventricular premature complexes (VPCs), we developed a new diagnostic method using a dot distribution pattern corresponding to VPCs recorded on a heart rate tachogram using ambulatory ECG monitoring data. We tested our hypothesis that widely scattered VPC dots on instantaneous heart rate tachograms indicate a constant VPC-VPC interval compatible with parasystole.
  
  
  RESULTS
  Patients with frequent VPCs > 5,000/day) were divided into two groups depending on the tachogram dot distribution patterns: group S (n = 10, aged 61 +/- 16 years) showed widely scattered VPC dot distribution, whereas group F (n = 10, 60 +/- 17 years) showed fixed VPC dot distribution limited to a narrow zone. Using digitized R-R interval data, full-day heart rate tachograms and VPC-VPC intervals were depicted simultaneously. Group S demonstrated constant basic VPC-VPC intervals (1,285 to 2,052 msec, mean 1,738 +/- 219), with a coefficient of variation (CV) of 0.061 +/- 0.018. Their VPC coupling intervals were markedly variable (651 +/- 113 msec; CV = 0.193 +/- 0.034). Each patient's basic VPC-VPC intervals showed small diurnal alterations (minimum -13% +/- 3% to maximum +15% +/- 6%). VPC-VPC intervals in group F were not constant and showed marked variation. Group F VPC coupling intervals were shorter and constant (480 +/- 30 msec, P = 0.0002; with CV = 0.076 +/- 0.013, P < 0.0001).
  
  
  CONCLUSIONS
  Ventricular parasystole with constant VPC-VPC intervals consistently became evident based on VPC dot patterns recorded on heart rate tachograms.
authors.affiliation: Department of Cardiology, Koshigaya Hospital, Dokkyo University School of Medicine, Saitama, Japan. tkyng@dokkyomed.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Takayanagi
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: H
authors.initials: H
authors.lastname: Kamishirado
authors.forename: Y
authors.initials: Y
authors.lastname: Sakai
authors.forename: T
authors.initials: T
authors.lastname: Fujito
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Hayashi
authors.forename: S
authors.initials: S
authors.lastname: Morooka
authors.forename: N
authors.initials: N
authors.lastname: Ikeda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005117:Cardiac Complexes, Premature / Q000175:diagnosis* / Q000503:physiopathology; D002940:Circadian Rhythm; D003937:Diagnosis, Differential; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012849:Sinoatrial Node / Q000503:physiopathology; D013997:Time Factors; D018754:Ventricular Dysfunction / Q000175:diagnosis* / Q000503:physiopathology