Diagnostic value of coronary flow reserve assessment by dynamic 99mTc-MIBI SPECT-CZT gamma camera for the detection of coronary artery disease. (14th October 2021) - Cygulska, K M
Abstract: Background: Coronary flow reserve (CFR) obtained by dynamic acquisition of myocardial blood flow using 99mTc-MIBI SPECT-CZT gamma camera may be useful to diagnose myocardial perfusion defects in patients with coronary artery disease (CAD). Purpose: To assess the feasibility and diagnostic value of SPECT-derived CFR in patients with suspected of confirmed CAD. Methods: The study group comprised 55 patients (pts) (43.6% females, mean age 64.6±8.4 years) with suspected CAD who were referred for scheduled coronary angiography. All pts underwent myocardial perfusion study with solid-state CZT nuclear camera (dipyridamole stress protocol) to calculate myocardial blood flow reserve. We measured total CFR, as well as CFR in three coronary territories: left anterior descending artery (LAD CFR), right coronary artery (RCA CFR) and left circumflex artery (LCx CFR). Results: On coronary angiography 27 pts were found to have significant CAD (at least one major coronary artery ≥70% narrowed). Mean total CFR in pts with CAD was lower than in pts without CAD (1.73±0.59 vs 2.09±0.56, respectively, p=0.02). Similar differences were noted in LAD territory (1.47±0.57 vs 2.00±0.57; respectively, p=0.004) and RCA territory (1.55±0.54 vs 2.01±0.62; respectively, p=0.03). However, the differences in LCx CFR between CAD and no-CAD group did not reach statistical significance. Modest, but significant correlations were detected between LAD CFR and the percentage of LAD stenosis (r=−0.3; p=0.02). Total CFR has acceptable diagnostic value for detecting significant CAD (AUC=0.672; p=0.03). The criterion with the highest diagnostic accuracy was CFR <1.8 – its sensitivity was 63%, specificity 71.4%, and overall accuracy 67%. In analysis of coronary territories the highest diagnostic value was achieved for CFR LAD (AUC=0.744; p=0.007). Conclusions: SPECT-derived CFR provides acceptable diagnostic accuracy for the detection of significant CAD. FUNDunding Acknowledgement: Type of funding sources: None.