title: Phase analysis in patients with reversible perfusion defects and normal coronary arteries at angiography.
abstract: OBJECTIVE
  A count-based new technique from gated myocardial perfusion single-photon emission tomography (gMPS) was developed to allow the phase analysis providing information about the left ventricular (LV) regional discordance in contractility which is a measure of LV dyssynchrony. Since the phase analysis provides data for evaluating the dyssynchronous LV contraction, it has an important role in diagnosis and management of patients with left ventricular dysfunction. The aim of the study was to assess the presence of left ventricular dyssynchrony in patients with reversible perfusion defects on gMPS scans and normal or near normal coronary arteries at angiography.
  
  
  METHODS
  32 patients (19 men, 59 %) with reversible mild perfusion defects on gMPS and normal coronary angiogram were retrospectively enrolled in the study. The peak of the phase histogram, the standard deviation of the phase distribution (PSD), the width of the band (PHB), and the symmetry and peakedness of the phase histogram, which are the assessment parameters for the LV dyssynchrony, were calculated from gMPS scans of patients by means of the phase analysis.
  
  
  RESULTS
  Although, five quantitative variables are derived from the phase analysis of gMPS, PSD and PHB are two quantitative indices to assess LV global mechanical dyssynchrony and measurements of PSD (men 24.96 ± 7.31, women 24.26 ± 10.07) and PHB (men 70.1 ± 13.99, women 71.0 ± 30.4) were significantly higher than the those reported in the literature (p < 0.001). No significant differences in gMPS phase analysis indices were found between both sexes except kurtosis.
  
  
  CONCLUSIONS
  As a conclusion, this study provides the phase analysis to detect LV mechanical dyssynchrony as new evidence supporting the concept that an abnormal scintigraphy finding, rather than being false-positive, may be an early marker of vasomotion changes associated with occult atherosclerosis in patients with normal coronary angiography findings.
authors: Department of Nuclear Medicine, Gülhane Military Medical Academy and School of Medicine, 06018 Ankara, Turkey. aokaracali@yahoo.com
authors: Alper O
authors: AO
authors: Karacalioglu
authors: Sevket
authors: S
authors: Balta
authors: Ozdes
authors: O
authors: Emer
authors: Sait
authors: S
authors: Demirkol
authors: Turgay
authors: T
authors: Celik
authors: Mehmet
authors: M
authors: Ozguven
mesh_terms: D000328:Adult; D000368:Aged; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000150:complications / Q000000981:diagnostic imaging*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D000091402:Prohibitins; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology; D055815:Young Adult