title: Pulse wave as an alternate signal for data synchronization during gated myocardial perfusion SPECT imaging.
abstract: OBJECTIVE
  Proper identification of the cardiac cycle is essential for gated SPECT myocardial perfusion imaging. We have developed an alternate method of ECG for gating, that is, using the peripheral pulse wave (PW) as the triggering signal for gated SPECT acquisition. The aim of this study is to compare the use of this method of gating with the standard ECG trigger.
  
  
  METHODS
  We tested the PW triggering by comparing it with the ECG trigger. We evaluated 33 patients (25 males, 8 females), average age of 61 years (39-80) referred for stress myocardial perfusion imaging. Data from all patients were acquired twice and were processed by CEqual and QGS software. We compared the left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volumes (EDV, ESV). Paired t test and Pearson correlation coefficient were used for comparison.
  
  
  RESULTS
  The mean LVEF, EDV, and ESV calculated with the ECG trigger were 0.52, 120, and 64, respectively, those with the pulse-wave trigger were 0.48, 126, and 71, respectively. Mean paired difference for LVEF was -0.034 (P<0.001), for EDV 5.9 (P=0.012), and for ESV 7.9 (P<0.001). Pearson correlation coefficient for LVEF was 0.955, for EDV 0.987, and for ESV 0.991 (P<0.001 for all correlations).
  
  
  CONCLUSIONS
  Triggering of gated-data acquisition by the PW is feasible. Quantitative parameters of cardiac function correlate highly with those obtained from the ECG trigger and the absolute differences are not clinically significant across a wide range of values.
authors.affiliation: Department of Nuclear Medicine, Charles University, Third Medical Faculty, Prague, Czech Republic. lang@fnkv.cz
authors.forename: Otto
authors.initials: O
authors.lastname: Lang
authors.forename: Helena
authors.initials: H
authors.lastname: Trojanova
authors.forename: Helena R
authors.initials: HR
authors.lastname: Balon
authors.forename: Ivana
authors.initials: I
authors.lastname: Kunikova
authors.forename: Milos
authors.initials: M
authors.lastname: Bilwachs
authors.forename: Martin
authors.initials: M
authors.lastname: Penicka
authors.forename: Milan
authors.initials: M
authors.lastname: Kaminek
authors.forename: Miroslav
authors.initials: M
authors.lastname: Myslivecek
mesh_terms: D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011674:Pulse / Q000379:methods*; D012815:Signal Processing, Computer-Assisted; D013318:Stroke Volume; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016277:Ventricular Function, Left