This study evaluated the accuracy of 99mTc SPECT in predicting restenosis after primary successful PTCA.
Methods: Thirty-seven patients with equivocal symptom-limited exercise stress testing were evaluated. All patients underwent separate day exercise-rest 99mTc-sestamibi SPECT. The perfusion studies were evaluated using three different methods of analysis: visual inspection, semiquantitative and quantitative polar map analysis. The perfusion studies were interpreted in absence of a pre-PTCA scan. All patients underwent a control coronary angiography within 1 mo.
Results: Sensitivity and specificity of 99mTc-sestamibi SPECT in predicting restenosis were 87.5-78%, 50-65% and 75-74% for visual inspection, semiquantitative and quantitative polar map analysis, respectively. Sensitivity and specificity related to the vascular territories were: LAD territory 93-73% (qualitative analysis), 53-60% (semiquantitative analysis), 80-67% (quantitative analysis); LCX territory 83-100% (qualitative analysis); and 33-100% (semiquantitative analysis), 67-100% (quantitative analysis); and RCA territory 67-80% (qualitative analysis), 67-60% (semiquantitative analysis), 67-80% (quantitative analysis).
Conclusion: These data suggest that 99mTc-sestamibi SPECT is a useful noninvasive tool in the follow-up evaluation of patients who have undergone angiographically successful coronary angioplasty even in the absence of a pre-PTCA perfusion study.