title: Cardiac MRI assessment of right ventricular function: impact of right bundle branch block on the evaluation of cardiac performance parameters.
abstract: OBJECTIVE
  Right ventricular (RV) function represents a prognostic marker in patients with corrected congenital heart disease. In up to 80 % of these patients, right branch bundle block (RBBB) exists and leads to asynchronous ventricular contraction. The aim of this retrospective study was to evaluate the change of RV performance parameters considering delayed RV end-systolic contraction.
  
  
  METHODS
  RV volumes of 33 patients were assessed twice: 1) not taking account of RBBB (group I), and 2) considering RBBB (group II). According to the RV ejection fraction (EF) for both groups, RV function was classified in different categories (>50 % = normal, 40-50 % = mildly-, 30-40 % = moderately-, <30 % = severely-reduced).
  
  
  RESULTS
  The mean time difference between maximal systolic contraction of the septum and RV free wall was 90.7 ms ± 42.6. Consequently, RV end-systolic volume was significantly decreased in group II (p < 0.001). Accordingly, RV stroke volume and RV EF were significantly higher in group II (p < 0.001). There was also a significant change in the assessment of RV function (p < 0.02).
  
  
  CONCLUSIONS
  RBBB induced delayed RV contraction can be detected at CMR. Ignoring the RV physiology in RBBB patients leads to a statistically significant underscoring of RV performance parameters.
  
  
  CONCLUSIONS
  • Right branch bundle block leads to an asynchronous ventricular contraction • In CMR, a delayed right ventricular contraction due to RBBB can be detected • Ignoring RV physiology in RBBB patients leads to underscoring of RV performance.
authors.affiliation: Division of Pediatric Radiology, Department of Radiology, Medical University of Graz, Auenbruggerplatz 34, 8036, Graz, Austria. robert.marterer@medunigraz.at.
authors.forename: Robert
authors.initials: R
authors.lastname: Marterer
authors.affiliation: Department of Ultrasonography, First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, Peple's Republic of China, 830011. 398023151@qq.com.
authors.forename: Zeng
authors.initials: Z
authors.lastname: Hongchun
authors.affiliation: Division of Pediatric Radiology, Department of Radiology, Medical University of Graz, Auenbruggerplatz 34, 8036, Graz, Austria. sebastian.tschauner@medunigraz.at.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Tschauner
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, Graz, Austria. martin.koestenberger@medunigraz.at.
authors.forename: Martin
authors.initials: M
authors.lastname: Koestenberger
authors.affiliation: Division of Pediatric Radiology, Department of Radiology, Medical University of Graz, Auenbruggerplatz 34, 8036, Graz, Austria. erich.sorantin@medunigraz.at.
authors.forename: Erich
authors.initials: E
authors.lastname: Sorantin
mesh_terms: D000328:Adult; D002037:Bundle-Branch Block / Q000150:complications / Q000503:physiopathology*; D005260:Female; D006330:Heart Defects, Congenital / Q000150:complications / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018497:Ventricular Dysfunction, Right / Q000150:complications / Q000503:physiopathology*; D055815:Young Adult
keywords: Bundle-branch block; Congenital heart defects; Magnetic resonance imaging; Tetralogy of Fallot; Ventricular ejection fraction