title: Characteristics of premature ventricular contractions in healthy children and their impact on left ventricular function.
abstract: There are few data regarding the characteristics of premature ventricular contractions (PVCs) in healthy children and their impact on left ventricular (LV) function.
  
  
  
  The purpose of this study was to assess the prevalence of LV systolic dysfunction in children with frequent PVCs (≥10%) and determine whether it is associated with PVC characteristics (e.g., proportion, coupling interval, width, and/or morphology).
  
  
  
  We conducted a single-center cohort study of children with structurally normal hearts and PVC burden ≥10% by 24-hour Holter monitoring performed between 2008 and 2012. Clinical, arrhythmic, and echocardiographic data were reviewed at baseline and during follow-up.
  
  
  
  A total of 47 children (22 female [47%], mean age 8.2 ± 6.5 years) had a mean PVC burden of 20.9 ± 11.9% at baseline. The PVC coupling interval averaged 430 ± 110 ms, with a PVC width of 118 ± 27 ms. PVCs were monomorphic in 44 patients (94%). Although no patient had severe cardiomyopathy, 7 (15%) had reduced shortening fraction (Z-score <-2). A strong association was observed between PVC coupling interval and LV shortening fraction Z-score <-2.0 (area under the curve 0.95 ± 0.03, P <.001). A cutoff value <365 ms yielded the greatest discriminatory ability (Youden J-statistic 0.72, sensitivity 85.7%, specificity 86.5%). PVC proportion, width, and morphology were not significantly associated with LV shortening fraction. During 4.0 ± 2.8 years of follow-up, the PVC burden decreased from a median of 18% to 1.5% (P<.001).
  
  
  
  PVCs in children with structurally normal hearts are associated with a relatively benign course, with spontaneous resolution in most children. Mild LV systolic dysfunction, observed in 15%, is strongly correlated with a shorter coupling interval (<365 ms).
authors.affiliation: Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Abadir
authors.affiliation: Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Blanchet
authors.affiliation: Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Anne
authors.initials: A
authors.lastname: Fournier
authors.affiliation: Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Wadi
authors.initials: W
authors.lastname: Mawad
authors.affiliation: Montreal Health Innovations Coordinating Center (MHICC), Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Shohoudi
authors.affiliation: Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Nagib
authors.initials: N
authors.lastname: Dahdah
authors.affiliation: Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada; Montreal Health Innovations Coordinating Center (MHICC), Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada. Electronic address: paul.khairy@umontreal.ca.
authors.forename: Paul
authors.initials: P
authors.lastname: Khairy
mesh_terms: D000293:Adolescent; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015716:Electrocardiography, Ambulatory / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D013223:Statistics as Topic; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D016277:Ventricular Function, Left; D018879:Ventricular Premature Complexes / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology
keywords: Cardiomyopathy; Children; Coupling interval; Left ventricular function; Premature ventricular contractions