title: Short-term fluctuations in sinus cycle length after premature ventricular beats in patients with hypertrophic cardiomyopathy and myocardial infarction.
abstract: BACKGROUND
  Sinus cycle length has been reported to fluctuate after a ventricular premature beat (VPB). The purpose of this study was to assess the short-term fluctuations of sinus cycle length in patients with hypertrophic cardiomyopathy (HCM) and prior myocardial infarction (MI).
  
  
  METHODS
  The relative deviation of RR intervals from the mean of the last two RR intervals preceding a VPB were calculated during the 20 subsequent beats following the VPB from Holter recordings in 92 patients with non-obstructive HCM, 57 patients with prior MI and 54 healthy controls.
  
  
  RESULTS
  In controls, the deviations of the RR intervals were negative for several beats after a VPB and subsequently changed to positive before returning to the baseline. Similar changes in RR intervals following a VPB were exhibited in HCM patients; however, the late positive deviations of RR intervals were more marked than in controls. By contrast, in patients with prior MI, the early negative deviations of RR intervals were smaller compared with controls, and the deviations returned to the baseline without incidence of the positive changes.
  
  
  CONCLUSIONS
  Short-term fluctuations in sinus cycle length after a VPB differed exclusively among HCM patients, prior MI patients, and healthy controls.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kawasaki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Azuma
authors.forename: Takuya
authors.initials: T
authors.lastname: Taniguchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Asada
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Kamitani
authors.forename: Shingo
authors.initials: S
authors.lastname: Kawasaki
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Matsubara
authors.forename: Hiroki
authors.initials: H
authors.lastname: Sugihara
mesh_terms: D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000503:physiopathology*; D016022:Case-Control Studies; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology*; D013997:Time Factors; D018879:Ventricular Premature Complexes / Q000209:etiology / Q000503:physiopathology*