title: Factors associated with progression of right ventricular enlargement and dysfunction after repair of tetralogy of Fallot based on serial cardiac magnetic resonance imaging.
abstract: OBJECTIVE
  Although progressive right ventricular (RV) enlargement (RVE) is common in patients with pulmonary regurgitation after tetralogy of Fallot (TOF) repair, the rate of RVE and progression of RV dysfunction varies among patients. The present study aimed to investigate the independent predictors of rapid RVE and RV dysfunction after the repair of TOF, using serial cardiac magnetic resonance imaging (MRI).
  
  
  METHODS
  The study included consecutive patients who underwent serial cardiac MRI more than twice between January 2005 and March 2015 after the repair of TOF. Patients who underwent surgical pulmonary valve implantation or any transcatheter cardiac intervention between two consecutive MRI assessments were excluded. The study patients were divided into rapid RVE and non-rapid RVE groups according to the rate of RVE. The upper first quartile of the patients was considered to have rapid RV dilatation (defined as rapid RVE group). Remaining patients in other three quartiles were included in the non-rapid RVE group. Additionally, the study patients were divided into rapid right ventricular ejection fraction (RVEF) change and non-rapid RVEF change groups according to the rate of change in the RVEF. The groups were compared, and multiple logistic regression analyses were performed to identify the independent risk factors for rapid RVE and RV dysfunction.
  
  
  RESULTS
  The study included 116 patients. The mean number of cardiac MRI assessments performed in each patient was 2.8 ± 0.8. The time to the initial MRI assessment after TOF repair was 14.2 ± 10.3 years, and the interval between the initial and last MRI assessments was 4.5 ± 2.2 years. The mean right ventricular end-diastolic volume index (RVEDVi) change rate was 2.7 ± 6.1 ml/m(2)/year. The initial RVEDVi was not different between the rapid RVE and non-rapid RVE groups. Restrictive RV physiology was an independent risk factor for rapid RVE (odds ratio, 3.64; 95% confidence interval, 1.263-10.494; P = 0.02), and a previous palliative shunt procedure was a negative predictor for rapid RVE (odds ratio, 0.08; 95% confidence interval, 0.010-0.778; P = 0.03). We did not find any predictive factors for rapid RV dysfunction.
  
  
  CONCLUSIONS
  In patients with rapid RV dilatation, restrictive RV physiology might be frequently noted at the initial MRI assessment. Therefore, careful follow-up may be necessary in patients with restrictive RV physiology to determine the optimal timing of pulmonary valve implantation.
authors.affiliation: Division of Cardiovascular Surgery, Severance Cardiovascular Hospital, Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Yu Rim
authors.initials: YR
authors.lastname: Shin
authors.affiliation: Division of Pediatric Cardiology, Severance Cardiovascular Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jo Won
authors.initials: JW
authors.lastname: Jung
authors.affiliation: Division of Pediatric Cardiology, Severance Cardiovascular Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Nam Kyun
authors.initials: NK
authors.lastname: Kim
authors.affiliation: Division of Pediatric Cardiology, Severance Cardiovascular Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Choi
authors.affiliation: Department of Radiology, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Division of Cardiovascular Surgery, Severance Cardiovascular Hospital, Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hong Ju
authors.initials: HJ
authors.lastname: Shin
authors.affiliation: Division of Cardiovascular Surgery, Severance Cardiovascular Hospital, Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Young-Hwan
authors.initials: YH
authors.lastname: Park
authors.affiliation: Division of Cardiovascular Surgery, Severance Cardiovascular Hospital, Department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea hank@yuhs.ac.
authors.forename: Han Ki
authors.initials: HK
authors.lastname: Park
mesh_terms: D002648:Child; D002675:Child, Preschool; D004108:Dilatation, Pathologic / Q000000981:diagnostic imaging / Q000209:etiology; D018450:Disease Progression; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D011665:Pulmonary Valve Insufficiency / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D013771:Tetralogy of Fallot / Q000601:surgery*; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000209:etiology*
keywords: Magnetic resonance imaging; Progressive right ventricular enlargement; Tetralogy of Fallot