title: Effect of sex, age, and weight on ejection fraction and end-systolic volume reference limits in gated myocardial perfusion SPECT.
abstract: BACKGROUND
  The left-ventricular ejection fraction (EF) and end-systolic volume (ESV) are strong predictors of prognosis for cardiac death. Gated myocardial perfusion single-photon emission computed tomography (gSPECT) may be used to measure ESV and EF. However, systematic differences may exist between referred populations. Our aim was to derive male and female reference limits for left-ventricular functional parameters, and determine the effect of age, weight, and body surface area (BSA).
  
  
  RESULTS
  The ejection fraction and ESV were derived using QGS software for 127 patients with normal gSPECT studies. The lower reference limits of EF were 46.2% and 55.6% for men and women, respectively. The upper reference limits of ESV were 30.4 mL and 21.4 mL, and 15.7 mL/m(2) and 11.1 mL/m(2), when indexed to BSA for men and women, respectively. There was no correlation between EF and age, weight, or BSA (P > .05). There was a small decrease in ESV with age, and an increase with weight and BSA (P < .05). The sex-specific differences remained after adjusting for confounding variables.
  
  
  CONCLUSIONS
  We demonstrated a significant sex difference for all functional parameters measured, and we established the influence of patient age and weight. Local reference limits for ESV and EF have been established, and the latter are transferable to other departments operating similar protocols.
authors.affiliation: Regional Medical Physics Department, Royal Victoria Infirmary, Newcastle upon Tyne Hospitals National Health Service Foundation Trust, Newcastle upon Tyne, United Kingdom. richard.peace@nuth.nhs.uk
authors.forename: Richard A
authors.initials: RA
authors.lastname: Peace
authors.forename: Philip C
authors.initials: PC
authors.lastname: Adams
authors.forename: Jim J
authors.initials: JJ
authors.lastname: Lloyd
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001835:Body Weight / Q000502:physiology*; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000706:statistics & numerical data*; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D012737:Sex Factors; D013223:Statistics as Topic; D013318:Stroke Volume / Q000502:physiology*; D013599:Systole / Q000502:physiology*; D015899:Tomography, Emission-Computed, Single-Photon / Q000706:statistics & numerical data*; D006113:United Kingdom / Q000453:epidemiology; D016276:Ventricular Function