title: Ultrafast assessment of left ventricular dyssynchrony from nuclear myocardial perfusion imaging on a new high-speed gamma camera.
abstract: OBJECTIVE
  To validate the ultrafast assessment of left ventricular (LV) dyssynchrony by phase analysis using high-speed nuclear myocardial perfusion imaging (MPI) on a new gamma camera with cadmium-zinc-telluride (CZT) solid-state detector technology.
  
  
  METHODS
  In 46 patients rest MPI with 960 MBq (99m)Tc-tetrofosmin was acquired on a dual-head detector SPECT camera (Ventri, GE Healthcare) and an ultrafast CZT camera (Discovery NM 530c, GE Healthcare) with acquisition times of 15 and 5 min, respectively. LV dyssynchrony was assessed using the Emory Cardiac Toolbox with established values for histogram bandwidth (male <62.4°; female <49.7°) and standard deviations (male <24.4°; female <22.1°) as the gold standard. Evaluating CZT scan times of 0.5, 1, 2, 3 and 5 min (list mode) in 16 patients revealed the preferred scan time to be 5 min, which was then applied in all 46 patients. Intraclass correlation and the level of agreement in dyssynchrony detection between the CZT and Ventri cameras were assessed.
  
  
  RESULTS
  In LV dyssynchrony the mean histogram bandwidths with the CZT camera (n = 8) and the Ventri camera (n = 9) were 123.3 ± 50.6° and 130.2 ± 43.2° (p not significant) and 42.4 ± 13.6° vs. 43.2 ± 12.7° (p not significant). Normal bandwidths and SD obtained with the CZT camera (35.9 ± 7.7°, 12.6 ± 3.5°) and the Ventri camera (34.8 ± 6.6°, 11.1 ± 2.1°, both p not significant) excluded dyssynchrony in 38 and 37 patients, respectively. Intraclass correlation and the level of agreement between the CZT camera with a 5-min scan time and the Ventri camera were 0.94 (p < 0.001, SEE 14.4) and 96% for histogram bandwidth and 0.96 (p < 0.001, SEE 3.9) and 98% for SD.
  
  
  CONCLUSIONS
  This ultrafast CZT camera allows accurate assessment of LV dyssynchrony with a scan time of only 5 min, facilitating repeat measurements which would potentially be helpful for parameter optimization for cardiac resynchronization therapy.
authors.affiliation: University Hospital Zurich, Ramistrasse, Zurich, Switzerland.
authors.forename: Aju P
authors.initials: AP
authors.lastname: Pazhenkottil
authors.forename: Ronny R
authors.initials: RR
authors.lastname: Buechel
authors.forename: Bernhard A
authors.initials: BA
authors.lastname: Herzog
authors.forename: Rene N
authors.initials: RN
authors.lastname: Nkoulou
authors.forename: Ines
authors.initials: I
authors.lastname: Valenta
authors.forename: Ursula
authors.initials: U
authors.lastname: Fehlmann
authors.forename: Jelena-Rima
authors.initials: JR
authors.lastname: Ghadri
authors.forename: Mathias
authors.initials: M
authors.lastname: Wolfrum
authors.forename: Lars
authors.initials: L
authors.lastname: Husmann
authors.forename: Philipp A
authors.initials: PA
authors.lastname: Kaufmann
mesh_terms: D000368:Aged; D002104:Cadmium; D005260:Female; D015902:Gamma Cameras; D006801:Humans; D016014:Linear Models; D008297:Male; D055414:Myocardial Perfusion Imaging / Q000295:instrumentation*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013691:Tellurium; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*; D015032:Zinc
chemical_list: C474490:CdZnTe; D002104:Cadmium; D015032:Zinc; D013691:Tellurium