title: Reduction of QRS duration after pulmonary valve replacement in adult Fallot patients is related to reduction of right ventricular volume.
abstract: OBJECTIVE
  Late after total correction, Fallot patients with a long QRS duration are prone to serious arrhythmias and sudden cardiac death. Pulmonary regurgitation is a common cause of right ventricular (RV) failure and QRS lengthening. We studied the effects of pulmonary valve replacement (PVR) on QRS duration and RV volume.
  
  
  RESULTS
  Twenty-six consecutive Fallot patients were evaluated both pre-operatively and 6-12 months post-operatively by cardiac magnetic resonance (CMR). In this study, we present the computer-assisted analysis of the standard 12-lead electrocardiograms closest in time to the CMR studies. For the whole group, QRS duration shortened by 6+/-8 ms, from 151+/-30 to 144+/-29 ms (P=0.002). QRS duration decreased in 18 of 26 patients by 10+/-6 ms, from 152+/-32 to 142+/-31 ms. QRS duration remained constant or increased slightly in eight of 26 patients by 3+/-3 ms, from 148+/-27 to 151+/-25 ms. CMR showed a decrease in RV end-diastolic volume from 305+/-87 to 210+/-62 mL (P=0.000004). QRS duration changes correlated with RV end-diastolic volume changes (r=0.54, P=0.01).
  
  
  CONCLUSIONS
  Our study shows that PVR reduces QRS duration. The amount of QRS reduction is related to the success of the operation, as expressed by the reduction in RV end-diastolic volume.
authors.affiliation: Department of Cardiology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
authors.forename: Bart Hooft
authors.initials: BH
authors.lastname: van Huysduynen
authors.forename: Alexander
authors.initials: A
authors.lastname: van Straten
authors.forename: Cees A
authors.initials: CA
authors.lastname: Swenne
authors.forename: Arie C
authors.initials: AC
authors.lastname: Maan
authors.forename: Henk J Ritsema
authors.initials: HJ
authors.lastname: van Eck
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Ernst E
authors.initials: EE
authors.lastname: van der Wall
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
authors.forename: Mark G
authors.initials: MG
authors.lastname: Hazekamp
authors.forename: Hubert W
authors.initials: HW
authors.lastname: Vliegen
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000473:pathology / Q000517:prevention & control*; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D017380:Hypertrophy, Right Ventricular / Q000473:pathology* / Q000503:physiopathology; D018810:Magnetic Resonance Angiography; D008297:Male; D011664:Pulmonary Valve / Q000601:surgery*; D011665:Pulmonary Valve Insufficiency / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D013771:Tetralogy of Fallot / Q000150:complications* / Q000473:pathology; D018497:Ventricular Dysfunction, Right / Q000473:pathology