[Comparison of the diagnostic value of rest 18F-FDG PET myocardial ischemic memory imaging and rest 99Tcm-MIBI SPECT myocardial perfusion imaging for obstructive coronary artery disease in patients with suspected unstable angina].

Abstract

Objective: To compare the diagnostic value of rest ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) myocardial ischemic memory imaging and rest ⁹⁹Tc^m-methoxyisobutylisonitrile (MIBI) single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for obstructive coronary artery disease (CAD) in patients with suspected unstable angina (UA). Methods: This prospective study included low-and medium-risk patients who presented with chest pain or discomfort at the Chest Pain Center or Cardiovascular Department of the Third Affiliated Hospital of Soochow University from September 2020 to June 2024. These patients, whose initial clinical assessments were negative but still suspected of UA, all underwent rest ⁹⁹Tc^m-MIBI SPECT MPI, rest ¹⁸F-FDG PET myocardial ischemic memory imaging, and invasive coronary angiography (ICA). Using ICA as the diagnostic gold standard, the diagnostic value of rest ⁹⁹Tc^m-MIBI SPECT MPI and rest ¹⁸F-FDG PET myocardial ischemic memory imaging were compared for obstructive CAD in suspected UA patients. The diagnostic performance was assessed using receiver operating characteristic curves. Results: A total of 274 patients with suspected UA were included, of whom 158 (57.7%) had ICA confirmed obstructive CAD [112 males(70.9%), aged (64.3±10.3) years], and 116 (42.3%) had no obstructive CAD [61 males(52.6%), aged (65.4±8.4) years].Rest ¹⁸F-FDG PET myocardial ischemic memory imaging demonstrated significantly higher sensitivity (67.7% vs 52.5%), specificity (90.5% vs 78.4%), positive predictive value (90.7% vs 76.9%), negative predictive value (67.3% vs 54.8%), accuracy (77.4% vs 63.5%), and the area under the curve [0.79 (95%CI: 0.74-0.84) vs 0.66 (95%CI: 0.60-0.71)] compared to rest ⁹⁹Tc^m-MIBI SPECT MPI (all P<0.05). The net reclassification improvement (NRI) index for the diagnosis of obstructive CAD using rest ¹⁸F-FDG PET myocardial ischemic memory imaging over ⁹⁹Tc^m-MIBI SPECT MPI was 0.27 (95%CI: 0.14-0.41), and the difference was statistically significant (P<0.05). Conclusion: Rest ¹⁸F-FDG PET myocardial ischemic memory imaging demonstrates superior diagnostic performance compared to ⁹⁹Tc^m-MIBI SPECT MPI for obstructive CAD in patients with suspected UA.