title: Minimal residual coronary obstructions in patients who suffered a first myocardial infarction. A prospective study comparing coronary angiography and exercise thallium scintigraphy.
abstract: The purpose of the present study was to correlate the presence of minimal coronary obstruction (< or = 50%) assessed by coronary angiography with the presence of myocardial scar and ischemia detected by thallium-201 myocardial perfusion imaging. The study included 83 consecutive patients (74 men and 9 women) with a mean age 55.4 +/- 8.5 years who suffered a first myocardial infarction and did not undergo thrombolytic therapy. In all patients, coronary angiography, left ventriculography, and exercise thallium-201 tomographic scintigraphy were performed within 3 to 5 months of the myocardial infarction. Coronary arteriograms showed minimal residual obstructions in 37 (45%) patients. Of a total of 54 patients with < or = 50% obstruction, 18 showed persistent defects and 22 reversible defects on thallium scintigrams. The present study showing estimated angiographic stenosis of < or = 50% as being responsible either for myocardial scar or myocardial ischemia on postexercise thallium scintigrams leads us to conclude that percent value of stenosis does not accurately predict the pathophysiologic significance of coronary atherosclerotic lesions in patients who suffer a myocardial infarction. After a first myocardial infarction, coronary angiographies and thallium-201 scintigrams are complementary for an optimal treatment strategy for selected subsets of patients.
authors.affiliation: St. Mary University Hospital, Department of Cardiology (LA n. 3), Lisbon, Portugal.
authors.forename: E
authors.initials: E
authors.lastname: Macieira-Coelho
authors.forename: G
authors.initials: G
authors.lastname: Cantinho
authors.forename: B B
authors.initials: BB
authors.lastname: da Costa
authors.forename: M
authors.initials: M
authors.lastname: Garcia-Alves
authors.forename: A P
authors.initials: AP
authors.lastname: Lacerda
authors.forename: I
authors.initials: I
authors.lastname: Dionisio
authors.forename: M
authors.initials: M
authors.lastname: Carvalho
authors.forename: F
authors.initials: F
authors.lastname: de Pádua
mesh_terms: D000328:Adult; D000368:Aged; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging; D017023:Coronary Angiography; D003327:Coronary Disease / Q000150:complications / Q000000981:diagnostic imaging*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology*; D011446:Prospective Studies; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes
chemical_list: D013794:Thallium Radioisotopes