title: Stress-first protocol for myocardial perfusion SPECT imaging with semiconductor cameras: high diagnostic performances with significant reduction in patient radiation doses.
abstract: OBJECTIVE
  Effective doses of 14 mSv or higher are currently being attained in patients having stress and rest myocardial perfusion imaging (MPI) single photon emission computed tomography (SPECT) performed on the same day with conventional protocols. This study aimed to assess the actual reduction in effective doses as well as diagnostic performances for MPI routinely planned with: (1) high-sensitivity cadmium zinc telluride (CZT) cameras, (2) very low injected activities and (3) a stress-first protocol where the normality of stress images may lead to avoiding rest imaging.
  
  
  METHODS
  During a 1-year period, 2,845 patients had MPI on a CZT camera, a single-day stress-first protocol and low injected activities (120 MBq of (99m)Tc-sestamibi at stress for 75 kg body weight and threefold higher at rest). The ability to detect > 50% coronary stenosis was assessed in a subgroup of 149 patients who also had coronary angiography, while the normalcy rate was assessed in a subgroup of 128 patients with a low pretest likelihood of coronary artery disease (<10%).
  
  
  RESULTS
  Overall, 33% of patients had abnormal MPI of which 34% were women and 34% were obese. The mean effective doses and the percentage of exams involving only stress images were: (1) 3.53 ± 2.10 mSv and 37% in the overall population, (2) 4.83 ± 1.56 mSv and 5% in the subgroup with angiography and (3) 1.96 ± 1.52 mSv and 71 % in the low-probability subgroup. Sensitivity and global accuracy for identifying the 106 patients with coronary stenosis were 88 and 80%, respectively, while the normalcy rate was 97 %.
  
  
  CONCLUSIONS
  When planned with a low-dose stress-first protocol on a CZT camera, MPI provides high diagnostic performances and a dramatic reduction in patient radiation doses. This reduction is even greater in low-risk subgroups with high rates of normal stress images, thus allowing the mean radiation dose to be balanced against cardiac risk in targeted populations.
authors.affiliation: Department of Nuclear Medicine, CHU-Nancy, Nancy, France, matperrin@yahoo.fr.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Perrin
authors.forename: Wassila
authors.initials: W
authors.lastname: Djaballah
authors.forename: Frédéric
authors.initials: F
authors.lastname: Moulin
authors.forename: Marine
authors.initials: M
authors.lastname: Claudin
authors.forename: Nicolas
authors.initials: N
authors.lastname: Veran
authors.forename: Laetitia
authors.initials: L
authors.lastname: Imbert
authors.forename: Sylvain
authors.initials: S
authors.lastname: Poussier
authors.forename: Olivier
authors.initials: O
authors.lastname: Morel
authors.forename: Cyril
authors.initials: C
authors.lastname: Besseau
authors.forename: Antoine
authors.initials: A
authors.lastname: Verger
authors.forename: Henri
authors.initials: H
authors.lastname: Boutley
authors.forename: Gilles
authors.initials: G
authors.lastname: Karcher
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Marie
mesh_terms: D000368:Aged; D002104:Cadmium; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000295:instrumentation / Q000379:methods*; D011829:Radiation Dosage; D019275:Radiopharmaceuticals / Q000009:adverse effects; D012666:Semiconductors; D017256:Technetium Tc 99m Sestamibi / Q000009:adverse effects; D013691:Tellurium; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation / Q000379:methods*; D015032:Zinc
chemical_list: C474490:CdZnTe; D019275:Radiopharmaceuticals; D002104:Cadmium; D017256:Technetium Tc 99m Sestamibi; D015032:Zinc; D013691:Tellurium