title: Comparison of techniques for the measurement of left ventricular function following cardiac transplantation.
abstract: BACKGROUND
  Assessment of graft function after cardiac transplantation is essential for patient management and clinical research. Previous studies have found that the left ventricular (LV) ejection fraction (EF) by echocardiography (echo), radionuclide ventriculography (RNV), and cardiovascular magnetic resonance (CMR) is discrepant in patients with heart failure.
  
  
  METHODS
  Twelve patients underwent LV EF assessment by echo, angiography (angio), RNV, and CMR one year following heart transplantation. The scans were analyzed independently in blinded fashion.
  
  
  RESULTS
  The mean EF was 63 +/- 6% by RNV, 66 +/- 6% by CMR, 70 +/- 12% by angio, and 74 +/- 4% by echo. Significant differences were found between CMR and echo (p < 0.001), RNV and echo (p < 0.001), and RNV and angio (p < 0.05). The correlation between the techniques was poor (r = 0.3-0.6), and the scatter plots also suggested considerable variations between techniques. This was confirmed by the wide Bland-Altman limits of agreement (ranging from 22 to 45%). These were particularly wide for comparisons with angiography (43-45%).
  
  
  CONCLUSIONS
  The EF measurement by echo, angio, RNV, and CMR are not interchangeable in patients following heart transplantation. The CMR and RNV provided the best agreement in EF and appear preferable for research studies. Echocardiography systematically overestimated LV EF and showed poor agreement with other techniques. Angiography overestimated LV function, and its routine use did not add to information gained from noninvasive studies.
authors.affiliation: Cardiovascular MR Unit, Royal Brompton Hospital, National Heart and Lung Institute, Imperial College, London, UK. nickbellenger@doctors.org.uk
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Bellenger
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Marcus
authors.forename: Kim
authors.initials: K
authors.lastname: Rajappan
authors.forename: Magdi
authors.initials: M
authors.lastname: Yacoub
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Banner
authors.forename: Dudley J
authors.initials: DJ
authors.lastname: Pennell
mesh_terms: D017023:Coronary Angiography / Q000379:methods*; D004452:Echocardiography / Q000379:methods*; D016027:Heart Transplantation; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015635:Radionuclide Ventriculography / Q000379:methods*; D013318:Stroke Volume / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology*