title: Coupling Interval Ratio Is Associated with Ventricular Premature Complex-Related Symptoms.
abstract: OBJECTIVE
  Frequent ventricular premature complex (VPC) is one of the most common arrhythmia syndromes. Symptoms observed frequently with this arrhythmia syndrome remain limited. We sought to identify predictors of VPC-related symptoms by analyzing demographic information, VPC burden, and VPC surface electrocardiogram characteristics.
  
  
  METHODS
  We prospectively enrolled 109 patients with idiopathic outflow tract VPCs (63 males, 49±16 years old). They were divided into Group A (n=30, without VPC-related symptoms of palpitations or "dropped beats") and Group B (n=79, with VPC-related symptoms). Measured parameters were sinus and VPC QRS width, coupling interval (CI) between the previous sinus beat and VPC, CI ratio (%, CI/sinus cycle length), post-VPC CI and CI ratio, and VPC amplitude.
  
  
  RESULTS
  Both groups had similar age (p=0.22), daily VPC burden (p=0.15), and VPC site of origin (p=0.36). The VPC CI ratio was higher in Group B (60±15%) than in Group A (49±22%) (p=0.01).
  
  
  CONCLUSIONS
  VPC-related symptoms are associated with a higher VPC CI ratio (>50%). The physiologic basis for these results deserves further study.
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyoung-Min
authors.initials: KM
authors.lastname: Park
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sung Il
authors.initials: SI
authors.lastname: Im
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kwang Jin
authors.initials: KJ
authors.lastname: Chun
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jin Kyung
authors.initials: JK
authors.lastname: Hwang
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Seung-Jung
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: June Soo
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young Keun
authors.initials: YK
authors.lastname: On
keywords: Arrhythmias, cardiac; Electrocardiography; Ventricular premature complexes