title: Assessment of myocardial viability in patients with previous myocardial infarction by using single-photon emission computed tomography with a new metabolic tracer: [123I]-16-iodo-3-methylhexadecanoic acid (MIHA). Comparison with the rest-reinjection thallium-201 technique.
abstract: OBJECTIVE
  We compared the ability of rest single-photon emission computed tomography (SPECT) with [123I]-16-iodo-3-methylhexadecanoic acid (MIHA) and the thallium-201 (Tl-201) rest-reinjection technique to detect myocardial viability after infarction.
  
  
  BACKGROUND
  After myocardial infarction, MIHA frequently shows increased uptake in the areas with exercise Tl-201 defects (mismatch), even in patients with an irreversible Tl-201 reinjection defect. Whether such increased uptake is indicative of ischemic but viable myocardium is not known.
  
  
  METHODS
  We studied 38 patients who 1) underwent exercise SPECT Tl-201 with rest-reinjection and rest SPECT with MIHA before undergoing percutaneous transluminal coronary angioplasty (PTCA) of an infarct-related coronary artery, and 2) were found to have successful revascularization at follow-up angiography. The relation between SPECT results before PTCA and subsequent improvement in left ventricular wall motion was assessed.
  
  
  RESULTS
  A mismatch was evident before PTCA in 51 of 76 infarct-related segments and correlated with subsequent improvement in wall motion (overall accuracy 71%), even for the 27 segments whose exercise defects remained irreversible after Tl-201 reinjection (overall accuracy 81%). The finding of a mismatch clearly enhanced the results provided by the finding of > or = 50% Tl-201 uptake as determined at redistribution (p < 0.05), but not as determined at reinjection, although there was a trend toward a better specificity for the findings of a mismatch.
  
  
  CONCLUSIONS
  MIHA is an efficient marker of viability inside exercise-underperfused areas after infarction, even in patients with irreversible Tl-201 reinjection defects. Assessment by conventional SPECT of a mismatch between results obtained with a metabolic tracer (MIHA) and a flow tracer analyzed at exercise (Tl-201) as a marker of myocardial viability is a promising area of research.
authors.affiliation: Department of Nuclear Medicine, Centre Hospitalier Universitaire, Nancy, France. n.danchin@CHU-nancy.fr
authors.forename: P Y
authors.initials: PY
authors.lastname: Marie
authors.forename: M
authors.initials: M
authors.lastname: Angioï
authors.forename: N
authors.initials: N
authors.lastname: Danchin
authors.forename: P
authors.initials: P
authors.lastname: Olivier
authors.forename: J M
authors.initials: JM
authors.lastname: Virion
authors.forename: A
authors.initials: A
authors.lastname: Grentzinger
authors.forename: G
authors.initials: G
authors.lastname: Karcher
authors.forename: Y
authors.initials: Y
authors.lastname: Juillière
authors.forename: D
authors.initials: D
authors.lastname: Fagret
authors.forename: F
authors.initials: F
authors.lastname: Cherrier
authors.forename: A
authors.initials: A
authors.lastname: Bertrand
mesh_terms: D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D002470:Cell Survival; D003251:Constriction, Pathologic; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy; D009206:Myocardium / Q000473:pathology; D010169:Palmitic Acids; D011446:Prospective Studies; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D007457:Iodine Radioisotopes; D010169:Palmitic Acids; D013794:Thallium Radioisotopes; C086354:16-iodo-3-methylhexadecanoic acid