title: Sex-specific normal limits of left ventricular ejection fraction and volumes estimated by gated myocardial perfusion imaging in adult patients in Taiwan: a comparison between two quantitative methods.
abstract: BACKGROUND
  The left ventricular (LV) ejection fraction (EF) and end-diastolic and end-systolic volumes are strong predictors for prognosis of cardiac death. Quantitative-gated myocardial perfusion single-photon emission computed tomography (SPECT) is widely used to measure LV functional parameters. However, systematic differences may exist between referred populations. We sought to derive sex-specific normal values for LV functional parameters obtained using two quantitative methods.
  
  
  METHODS
  Among 1044 consecutive patients who underwent dipyridamole stress myocardial perfusion-gated 201Tl SPECT in 2008, a total of 140 (56 men) with normal perfusion imaging were selected. None had cardiac diseases or experienced cardiac events during 1-year follow-up. LV EF and end-diastolic and end-systolic volumes were calculated by quantitative-gated SPECT (QGS) and four-dimensional-myocardial single photon emission computed tomography (4D-MSPECT), respectively.
  
  
  RESULTS
  There was excellent intrareader and interreader reproducibility for both QGS and 4D-MSPECT algorithms. The differences in LV volumes and EF between the software packages were small. High prevalence of small heart was noted in the study population, especially in women (>60%). Volumetric measures were significantly greater (P<0.001) in men than in women, even after adjustment for body surface area. Women had a higher LV EF than men when using QGS methods, but not when using the 4D-MSPECT method. Compared with 4D-MSPECT, sex remained significantly associated with EF determined by QGS methods, independent of age and body weight.
  
  
  CONCLUSIONS
  LV functional parameters determined by means of gated 201Tl SPECT need to be corrected for sex and algorithms. Separate reference values of LV EF and volumes need to be applied in both women and men depending on the software package used.
authors.affiliation: Department of Nuclear Medicine, Far Eastern Memorial Hospital, Taipei, Taiwan.
authors.forename: Shan-Ying
authors.initials: SY
authors.lastname: Wang
authors.forename: Mei-Fang
authors.initials: MF
authors.lastname: Cheng
authors.forename: Juey-Jen
authors.initials: JJ
authors.lastname: Hwang
authors.forename: Chi-Sheng
authors.initials: CS
authors.lastname: Hung
authors.forename: Yen-Wen
authors.initials: YW
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D000465:Algorithms; D001830:Body Surface Area; D001835:Body Weight; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography / Q000592:standards*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012727:Sex Characteristics; D013318:Stroke Volume / Q000502:physiology*; D013624:Taiwan; D016277:Ventricular Function, Left / Q000502:physiology*