Prognostic significance of silent myocardial ischemia on a thallium stress test.
The clinical significance of silent ischemia is not fully known. The purpose of this study was to determine whether the presence or absence of angina during a thallium stress test positive for ischemia was independently predictive of an adverse outcome. Two hundred thirty-four consecutive patients with ischemia on a thallium stress test were identified. Ischemia was defined as the presence of defect(s) on the immediate postexercise scans not in the distribution of prior infarctions that redistributed on 4-hour scans. During the test 129 patients had angina, defined as characteristic neck, jaw, arm, back or chest discomfort, while the remaining 105 patients had no angina. Follow-up ranged from 2 to 8.2 years (mean 5.2 +/- 2.1) and was successfully obtained in 156 patients. Eighty-two of the 156 patients had angina (group A) and 74 had silent ischemia (group S). Group A patients were significantly older (62 +/- 8 vs 59 +/- 8 years, p less than 0.05). There was no significant difference between the 2 groups in terms of sex, history of prior infarction or presence of left main/3-vessel disease. A larger percentage of patients in group A were receiving beta blockers (60 vs 41%, p less than 0.05) and nitrates (52 vs 36%, 0.05 less than p less than 0.10). There was a large number of cardiac events (myocardial infarction, revascularization and death) in both groups (37 of 82 [45%] in group A; 28 of 72 [38%] in group S) but no statistically significant difference between the groups. Similarly, life-table analysis revealed no difference in mortality between the 2 groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Heller
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LI
Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, New York 10032.
Tresgallo
M
M
Sciacca
R R
RR
Blood
D K
DK
Seldin
D W
DW
Johnson
L L
LL
D000787:Angina Pectoris / Q000000981:diagnostic imaging; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000401:mortality; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes; D013997:Time Factors
D013794:Thallium Radioisotopes