Quantitative assessment of intermediate stenosis of coronary arteries by single photon emission computed tomography with attenuation correction in comparison with fractional flow reserve

Abstract

Background. Fractional flow reserve (FFR) is currently used to determine the management of intermediate coronary artery stenosis. FFR more 0,80 used in clinical practice to guide revascularization. Advances in nuclear medicine single photon emission computed tomography with attenuation correction (SPECT/CT) require revaluation quantitative parameter noninvasive imaging in compared with FFR in the diagnosis of the functional significance intermediate stenosis coronary artery.
Materials and methods. In this study, 70 patients (mean age 57±5 years, 50 men, and 20 women) with ischemic heart disease and 50 to 70% coronary stenosis (target vessel). All perfusion scans were performed using a camera (BrightView XCT Philips) equipped with a low-energy, high-resolution collimator and with cardiac gating. Antianginal medication was discontinued 48 hours before the study, and patients abstained from caffeine for 24 hours prior to the study protocol one day stress (bicycle test)/rest use with 900 MBq (25mCi) of technetium 99m-MIBI. Coronaroangiography (CAG), which was defined as angiographic moderate (50–70%), was assessed by quantitative coronary angiography (QCA) and pressure wires received FFR.
Results. Normal FFR >or =0,8. Summed difference scores (SDS) in the left anterior descending (LAD) artery, right coronary artery (RCA) and ramus circumflexus (RCX) artery territory according to the 17 segment model were calculated with attenuation correction (AC) and no correction (NC). In order to evaluate the sensitivity and specificity used ROC- analysis. NC value SDS >3 predicts the existence of a reliable, persistent perfusion defects with a sensitivity of 96,4% and a specificity of 84,2%, the images attenuation correction (AC) SDS >4 (96,7% and 90,1%, respectively).
Conclusion. Method of SPECT/CT can be used to determine the hemodynamic significance of intermediate coronary artery stenosis. Quantitative assessment of myocardial perfusion SDS determined at SPECT/CT with attenuation correction is more sensitive and specific for the coronary artery stenosis evaluation.