RESUMO
Objective: To investigate the diagnostic efficiency and incremental value of quantitative myocardial blood flow measurements by Cadmium-Zine-Telluride (CZT) single photon emission computed tomography (SPECT) dynamic myocardial perfusion imaging (MPI) in patients with coronary artery disease (CAD) compared with traditional semi-quantitative measurements by MPI. Methods: This is a retrospective, cross-sectional study. We retrospectively analyzed clinical data of patients with suspected or known CAD, who underwent the dynamic MPI quantitative blood flow measurement of CZT SPECT in TEDA International Cardiovascular Hospital from October 2018 to December 2020. Clinical data, semi-quantitative parameters (stress score (SS), rest score (RS) and different score (DS)) and myocardial quantitative blood flow parameters (rest myocardial blood flow (rMBF), stress myocardial blood flow (sMBF) and myocardial flow reserve (MFR)) were analyzed. According to the results of coronary angiography, patients were divided into the stenosis group and the control group with coronary artery stenosis ≥50% or ≥75% as the diagnosis criteria. The differences of quantitative and semi-quantitative parameters between the two groups were compared, and the diagnostic efficacy was compared by receiver operating characteristic(ROC) curve. Results: A total of 98 patients with a mean age of (62.1±8.7) years were included in the study, including 66 males (67%). At the patient level, with the positive standard of coronary artery stenosis≥50%, the left ventricle (LV) stress MBF (LV-sMBF) ((1.36±0.45) ml·min-1·g-1) and LV-MFR (1.45±0.43) of the stenosis group were lower than the LV-sMBF ((2.09±0.64) ml·min-1·g-1) and LV-MFR (2.17±0.54) of control group; summed SS and summed DS were higher than control group (all P<0.05). With the positive standard of coronary artery stenosis ≥75%, the LV-sMBF ((1.19±0.34) ml·min-1·g-1) and LV-MFR (1.34±0.35) of stenosis group were lower than the LV-sMBF ((1.94±0.63) ml·min-1·g-1) and MFR (2.00±0.58) of control group; all semi-quantitative parameters were higher than control group (all P<0.05). At the vascular level, with coronary artery stenosis ≥50% as the diagnosis criteria, the sMBF ((1.26±0.49) ml·min-1·g-1) and MFR (1.35±0.46) of stenosis group were lower than the sMBF ((1.95±0.70) ml·min-1·g-1) and MFR (2.05±0.65) of control group; SS and DS were higher than control group (all P<0.05). With coronary artery stenosis≥75% as the diagnosis criteria, the sMBF ((1.12±0.41) ml·min-1·g-1) and MFR (1.25±0.38) of stenosis group were lower than the sMBF ((1.84±0.70) ml·min-1·g-1) and MFR (1.93±0.66) of control group; all semi-quantitative parameters were higher than control group (all P<0.05). With coronary artery stenosis≥50% as the diagnosis criteria and CAG as the reference standard, the AUC and 95%CI of myocardial quantitative blood flow parameters indicated by ROC curve for diagnosis of CAD were 0.830 (0.783-0.877). The sensitivity (86.1% vs. 61.5%), specificity (82.6% vs. 73.8%), positive predictive value (77.8% vs. 62.5%), negative predictive value (89.3% vs. 73.0%) and accuracy (84.0% vs. 68.7%) were all higher than the semi-quantitative parameters (all P<0.05). With coronary artery stenosis≥75% as the diagnosis criteria, the AUC and 95%CI of myocardial quantitative blood flow parameters indicated by ROC curve for diagnosis of CAD were 0.832(0.785-0.879). The sensitivity (89.2% vs. 67.6%), negative predictive value (95.5% vs. 86.2%) and accuracy (80.6% vs. 68.0%) were all higher than semi-quantitative parameters (all P<0.05). Conclusion: Compared with traditional SPECT MPI derived semi-quantitative parameters, diagnostic efficacy for CAD is higher using CZT SPECT quantitative myocardial blood flow parameters, this strategy thus has additional diagnostic benefits and incremental value on the diagnosis of CAD.
