title: Left ventricular function in response to dipyridamole stress: head-to-head comparison between82Rubidium PET and99mTc-sestamibi SPECT ECG-gated myocardial perfusion imaging.
abstract: OBJECTIVE
  Myocardial perfusion imaging (MPI) with99mTc-sestamibi (sestamibi) SPECT and rubidium-82 (82Rb) PET both allow for combined assessment of perfusion and left ventricular (LV) function. We sought to compare parameters of LV function obtained with both methods using a single dipyridamole stress dose.
  
  
  METHODS
  A group of 221 consecutive patients (65.2 ± 10.4 years, 52.9% male) underwent consecutive sestamibi and82Rb MPI after a single dipyridamole stress dose. Sestamibi and82Rb summed rest (SRS), stress (SSS) and difference (SDS) scores, and LV end-diastolic (EDV) and end-systolic (ESV) volumes and left ventricular ejection fraction (LVEF) were compared.
  
  
  RESULTS
  Bland-Altman analysis showed that with increasing ESV and EDV the difference between the two perfusion tracers increased both at rest and post-stress. The mean difference in EDV and ESV between the two perfusion tracers at rest could both be independently explained by the82Rb SDS and the sestamibi SRS. The combined models explained approximately 30% of the variation in these volumes between the two perfusion tracers (R2= 0.261, p = 0.005; R2= 0.296, p < 0.001, for EDV and ESV respectively). However, the mean difference in LVEF between sestamibi and82Rb showed no significant trend post-stress (R2= 0.001, p = 0.70) and only a modest linear increase with increasing LVEF values at rest (R2= 0.032, p = 0.009).
  
  
  CONCLUSIONS
  Differences in left ventricular volumes between sestamibi and82Rb MPI increase with increasing volumes. However, these differences did only marginally affect LVEF between sestamibi and82Rb. In clinical practice these results should be taken into account when comparing functional derived parameters between sestamibi and82Rb MPI.
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Maria Clementina
authors.initials: MC
authors.lastname: Giorgi
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Jose Claudio
authors.initials: JC
authors.lastname: Meneghetti
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Jose
authors.initials: J
authors.lastname: Soares
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Marisa
authors.initials: M
authors.lastname: Izaki
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Andréa
authors.initials: A
authors.lastname: Falcão
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Imada
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: William
authors.initials: W
authors.lastname: Chalela
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: de Oliveira
authors.affiliation: Department of Radiology and Nuclear Medicine and Molecular Imaging Service - Heart Institute of the University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Cesar
authors.initials: C
authors.lastname: Nomura
authors.affiliation: Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, P.O. Box 22700, 1100 DE, Amsterdam, The Netherlands. h.j.verberne@amc.uva.nl.
authors.forename: Hein J
authors.initials: HJ
authors.lastname: Verberne
mesh_terms: D000368:Aged; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; D004176:Dipyridamole / Q000494:pharmacology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D055414:Myocardial Perfusion Imaging; D049268:Positron-Emission Tomography; D012414:Rubidium Radioisotopes; D013312:Stress, Physiological / Q000187:drug effects; D017256:Technetium Tc 99m Sestamibi; D016277:Ventricular Function, Left / Q000187:drug effects* / Q000502:physiology
chemical_list: D012414:Rubidium Radioisotopes; D004176:Dipyridamole; D017256:Technetium Tc 99m Sestamibi
keywords: Myocardial perfusion imaging; Positron emission tomography; Single-photon emission computed tomography; Stress ejection fraction