Thallium reinjection versus standard stress/delay redistribution imaging for prediction of cardiac events.
OBJECTIVE
The purpose of this study was to compare thallium reinjection with standard stress/delay redistribution for the prediction of cardiac events.


BACKGROUND
Although thallium reinjection enhances the detection of viable myocardium, its contribution to prognosis over stress/delay redistribution in a general referral population has not been clearly evaluated.


METHODS
This retrospective analysis included 366 consecutive patients with coronary artery disease who underwent stress/delay redistribution imaging and thallium reinjection scintigraphy, with a mean follow-up of 33+/-12 months.


RESULTS
Cardiac events occurred in 48 patients (40 deaths, 8 myocardial infarctions). Of the 366 original patients, 159 demonstrated ischemia by stress/delay redistribution, 107 showed ischemia by reinjection only, and 100 showed infarction only. Cardiac events occurred in 20 patients (12.6%) with stress/delay redistribution, 13 patients (12%) with ischemia detected by thallium reinjection only and 15 patients (15%) with infarction only. The size of the reversible thallium defect by either stress/delay redistribution imaging or reinjection scintigraphy did not predict cardiac events. Independent predictors of cardiac events included left ventricular cavity size, the size of the abnormal perfusion defect and patient age.


CONCLUSIONS
Thallium reinjection does not contribute independent prognostic utility for cardiac events when compared with stress/delay redistribution. Left ventricular dilation and the size of the post-stress defect were predictors of cardiac events.
Zafrir
N
N
Nuclear Cardiology Unit, Beilinson Medical Center, Petah Tiqva, Israel.
Leppo
J A
JA
Reinhardt
C P
CP
Dahlberg
S T
ST
D000368:Aged; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D004108:Dilatation, Pathologic; D004176:Dipyridamole; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D015635:Radionuclide Ventriculography / Q000379:methods*; D012008:Recurrence; D012044:Regression Analysis; D012189:Retrospective Studies; D013794:Thallium Radioisotopes; D014665:Vasodilator Agents
D013794:Thallium Radioisotopes; D014665:Vasodilator Agents; D004176:Dipyridamole