Prediction of severe coronary artery disease and long-term outcome in patients undergoing vasodilator SPECT.
BACKGROUND
Vasodilator perfusion imaging has not been extensively evaluated for predicting severe coronary artery disease (CAD) or long-term prognosis.


RESULTS
The goals of this study were to develop a model to predict left main/3-vessel CAD in patients undergoing vasodilator thallium 201 imaging and coronary angiography (angiographic population) and to test the long-term prognostic value of this model in a separate cohort of patients who were not referred for angiography (prognostic population). In the angiographic population (n = 653) the chi2 value of the clinical model (containing the variables age, sex, and prior myocardial infarction) in the prediction of severe CAD was 32. The addition of 3 vasodilator Tl-201 variables (magnitude of ST-segment depression, summed reversibility score, and increased lung uptake) increased the model chi2 value to 114 (P <.001). Only 9% of predicted low-risk patients versus 57% of predicted high-risk patients had severe CAD. In the prognostic population (n = 521) survival rates free of cardiac death or myocardial infarction at 7 years were 91%, 73%, and 51%, respectively, for patient groups predicted to be at low, intermediate, and high risk of severe CAD (P <.001).


CONCLUSIONS
Clinical and vasodilator Tl-201 variables can accurately predict the risk of severe CAD. Stress Tl-201 variables add incremental information to clinical variables. The same model also predicts patient outcome.
Ho
K T
KT
Department of Internal Medicine and Cardiovascular Diseases, Mayo Clinic, Rochester, Minn 55905, USA.
Miller
T D
TD
Christian
T F
TF
Hodge
D O
DO
Gibbons
R J
RJ
D000241:Adenosine; D000368:Aged; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000401:mortality; D004176:Dipyridamole; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D015233:Models, Statistical; D011379:Prognosis; D012307:Risk Factors; D015996:Survival Rate; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents
D013794:Thallium Radioisotopes; D014665:Vasodilator Agents; D004176:Dipyridamole; D000241:Adenosine