title: QRS Duration Changes in Patients with Single Ventricle Physiology: Birth to 10 Years.
abstract: BACKGROUND
  QRS prolongation may be a predictor of mortality in certain forms of congenital heart disease. Minimal data exist describing changes in QRS duration in patients with single ventricles (SVs). The goal was to describe changes in QRS duration in patients with SV and to determine if differences existed between single right ventricle (sRV) versus single left ventricle (sLV) patients.
  
  
  METHODS
  Chart review was performed on patients with SV physiology. Patients were divided into sRV and sLV groups. QRS durations were measured monthly for the first 6 months, at 1 year, and then yearly until 10 years. t-tests were used for analysis.
  
  
  RESULTS
  One hundred sixty patients were evaluated (95 sRV, 65 sLV). The greatest change in QRS duration for the entire cohort occurred in the first 6 months of life versus 6 months to 10 years of age (1.81 ms/month vs 0.20 ms/month). sRV QRS durations were significantly longer than sLV QRS durations at 1 year (78.9 ± 12.6 ms vs 73.2 ± 11.9 ms), 2 year (81.7 ± 14.7 ms vs 73.4 ± 12.5 ms), 4 year (84.2 ± 12.1 ms vs 77.9 ± 16.4 ms), 6 year (90.8 ± 12.7 ms vs 83.4 ± 13.4 ms), 7 year (90.8 ± 16.5 ms vs 81.2 ± 16.6 ms), and 8 year (96.7 ± 13.6 ms vs 84.8 ± 13.9 ms) time points.
  
  
  CONCLUSIONS
  The greatest change in QRS duration in SV patients occurred in the first 6 months of life when these patients' ventricles were volume loaded. Differences in QRS duration between sRV and sLV patients occurred early in life. Further studies are needed to determine if minimizing volume load early in life decreases the rate of change in QRS duration.
authors.affiliation: Heart Center, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Sairah
authors.initials: S
authors.lastname: Khan
authors.affiliation: Heart Center, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Holly
authors.initials: H
authors.lastname: Nadorlik
authors.affiliation: Heart Center, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Naomi
authors.initials: N
authors.lastname: Kertesz
authors.affiliation: Heart Center, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Lisa
authors.initials: L
authors.lastname: Nicholson
authors.affiliation: Heart Center, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Pamela S
authors.initials: PS
authors.lastname: Ro
authors.affiliation: Heart Center, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Clifford L
authors.initials: CL
authors.lastname: Cua
mesh_terms: D000375:Aging; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006330:Heart Defects, Congenital / Q000150:complications / Q000503:physiopathology*; D006339:Heart Rate; D006352:Heart Ventricles / Q000002:abnormalities* / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Fontan; QRS duration; congenital heart disease; electrocardiogram