title: Gated spect myocardial perfusion scintigraphy for identifying septal perfusion artifacts in left bundle branch block.
abstract: OBJECTIVE
  To determine the role of gated Single Photon Emission Computed Tomography (SPECT) for accurate assessment of myocardial perfusion scintigraphy (MPS) of patients with left bundle branch block (LBBB).
  
  
  METHODS
  Analytical study.
  
  
  METHODS
  Punjab Institute of Nuclear Medicine (PINUM), Faisalabad, Pakistan, from June 2002 to April 2003.
  
  
  METHODS
  MPS data of patients with LBBB was analyzed. Resting gated SPECT MPS was performed after an injection of 740 MBq 99mTc-MIBI in 10 normal and 25 subjects with LBBB (with low probability of coronary artery disease). Visual and quantitative analyses were done on non-gated (NG), end diastolic (ED), end systolic (ES) images. Calculations included septal to lateral wall ratio (SLR), myocardial thickening (MT=% increase in counts during systole) at end systolic phase and myocardial thickening at peak level (% peak MT).
  
  
  RESULTS
  Septal hypoperfusion was noted in 19 (76%) patients on NG images and in only 1 (4%) patient on gated SPECT ED images. On NG images of LBBB group, SLR was lower than in controls (0.68+/-0.07 vs. 0.87+/-0.05, p<0.001). SLR of LBBB patients approached to that of control group in gated SPECT ED data (0.86+/-0.06 vs 0.88+/-0.06, p=ns). Myocardial thickening at ES for septum was markedly lower in LBBB group than in controls (21.83%+/-10.86 vs. 66.32%+/-20.15, p<0.001).
  
  
  CONCLUSIONS
  In patients with LBBB, reduced septal thickening results in artifactual septal perfusion defects. Gating the perfusion scintigraphy and reporting perfusion status on end diastolic frames in LBBB patients can eliminate these artifacts.
authors.affiliation: Department of Nuclear Cardiology, Punjab Institute of Nuclear Medicine, Adjacent Allied Hospital, Faisalabad, Pakistan. pinum@fsd.comsats.net.pk
authors.forename: Muhammad Shehzad
authors.initials: MS
authors.lastname: Afzal
authors.forename: Muhammad Babar
authors.initials: MB
authors.lastname: Imran
authors.forename: Naeem
authors.initials: N
authors.lastname: Aslam
authors.forename: Syed Javaid
authors.initials: SJ
authors.lastname: Khurshid
authors.forename: Muhammad Aleem
authors.initials: MA
authors.lastname: Khan
authors.forename: Javaid
authors.initials: J
authors.lastname: Irfan
authors.forename: Umer-I-
authors.initials: UI
authors.lastname: Farooq
authors.forename: Muhammad
authors.initials: M
authors.lastname: Shoaib
authors.forename: M Saeed
authors.initials: MS
authors.lastname: Akhtar
authors.forename: Khan
authors.initials: K
authors.lastname: Muhammad
authors.forename: Afzal
authors.initials: A
authors.lastname: Nadeem
mesh_terms: D000328:Adult; D000368:Aged; D016477:Artifacts; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging* / Q000473:pathology; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging; D005260:Female; D015637:Gated Blood-Pool Imaging; D006346:Heart Septum / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000473:pathology; D010154:Pakistan; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi