title: Enhanced detection of reversible myocardial hypoperfusion by technetium 99m-tetrofosmin imaging and first-pass radionuclide angiography after nitroglycerin administration.
abstract: BACKGROUND
  Reversal of ischemia after myocardial infarction by revascularization is worthwhile only if viability exists in a sufficiently large portion of the left ventricle.
  
  
  RESULTS
  To determine myocardial hypoperfusion reversibility and its influence on segmental and global function, we studied 50 patients after myocardial infarction. Three technetium 99m-tetrofosmin scintigraphies were performed: 1 at rest, 1 after 0.6 mg sublingual nitroglycerin (NTG), and 1 after injection at peak stress. First-pass multigated radionuclide angiography was obtained at rest and after NTG. Each patient also underwent a stress redistribution-reinjection thallium-201 scintigraphy. During stress 99mTc-tetrofosmin, 104 segments had normal uptake, 51 showed moderately reduced uptake, and 186 had severely reduced uptake. Of these 186 segments, 33 (18%) improved at rest, and 41 (22%) improved only after NTG. Fifty-nine (79%) of these segments with improved uptake were also found to have reversible defects on 201TI imaging. In the 26 patients with ventricular dysfunction, a 73% agreement was found between the functional and 99mTc-tetrofosmin uptake post-NTG improvement, whereas a 69% agreement was found with thallium reinjection. No significant differences were seen between 99mTc-tetrofosmin and 201T1 imaging.
  
  
  CONCLUSIONS
  Nitroglycerin administration during 99mTc-tetrofosmin scintigraphy improves the detection of myocardium with reversible hypoperfusion in patients with a previous myocardial infarction.
authors.affiliation: Institute of Cardiology, Havana, Cuba.
authors.forename: A
authors.initials: A
authors.lastname: Peix
authors.forename: A
authors.initials: A
authors.lastname: López
authors.forename: F
authors.initials: F
authors.lastname: Ponce
authors.forename: J
authors.initials: J
authors.lastname: Morales
authors.forename: A R
authors.initials: AR
authors.lastname: de la Vega
authors.forename: C S
authors.initials: CS
authors.lastname: Chesa
authors.forename: A M
authors.initials: AM
authors.lastname: Maltas
authors.forename: D
authors.initials: D
authors.lastname: García-Barreto
mesh_terms: D000328:Adult; D000368:Aged; D003326:Coronary Circulation; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging; D005996:Nitroglycerin / Q000494:pharmacology*; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011875:Radionuclide Angiography; D013794:Thallium Radioisotopes; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D013794:Thallium Radioisotopes; D014665:Vasodilator Agents; C078700:technetium tc-99m tetrofosmin; D005996:Nitroglycerin