Abstract：Objective: To investigate the correlation of the risk stratification of 99mTc-MIBI gated stress-rest myocardial perfusion imaging(MPI) and the global registry of acute coronary events(GRACE) risk score in patients with unstable angina(UA). Methods: Thirty-seven patients with determinated UA were enrolled in the study. At first, the GRACE risk scores were evaluated according to the baseline characteristics on admission. And then all the patients received the 99mTc-MIBI exercise or adenosine stress-rest gated MPI in two days. Based on the summed difference score(SDS) and post-stress left ventricular ejection fraction(LVEF) of MPI, the patients were classified into 2 groups: the low risk group and the moderate risk group. The correlation of the risk stratification assessed by MPI and the GRACE risk score were analysed. Results: All the 37 patients completed the 99mTc-MIBI gated stress-rest MPI successfully. Based on the risk stratification of MPI, 24 patients were in low risk group and 13 in moderate risk group. The GRACE risk scores in moderate risk group were obviously higher than those in low risk group(P<0.05). The relevant analysis showed that the GRACE risk score was positively correlated with the summed stress score(r＝0.561, P<0.01) and the summed difference score(r＝0.623, P<0.01), and had no relation with the summed rest score(r＝0.175, P>0.05). Conclusion: In UA patients, the GRACE risk score has certain predicting value in the risk stratification of MPI.
2008, Vol. 19 
