Coronary Flow Reserve Assessment in Patients with Cad by Dynamic Single-Photon Emission Computed Tomography

Abstract

Purpose: to assess the coronary flow reserve in patients with one, two and multi-vessel coronary artery diseases by dynamic SPECT using semiconductor (cadmium-zinctelluride)- based gamma camera.Material and methods.This work included 42 patients with stable coronary artery diseases. The first group consisted of 12 (28.6%) patients with single and two-vessel coronary artery disease (STCAD) (8 males and 4 females; mean age 61.5 ± 3.8 years) with intermediate (50–70%) and significant (>70%) coronary artery stenosis. Second group included 30 (71.4%) patients with multi- vessel coronary artery diseases (MVCAD) (22 males and 8 females; mean age 60.1 ± 4.3 years) with a lesion >70% in at least 2 major epicardial vessels according to invasive coronary angiography. All patients underwent rest-stress dynamic SPECT as well as conventional myocardial perfusion imaging with 99mTc-MIBI as a radiopharmaceutical. All scintigraphic images were acquired on the hybrid SPECT/CT unit (GE Discovery NM/CT 570C). Patient with STCAD underwent invasive FFR detection.Results.When comparing the results of MPI between the study groups, there were no significant differences. ROC analysis showed that the global MFR ≤ 1,42 allows to identify MVCAD with a sensitivity and specificity 68% and 86,4%, for PSM, these values are: 39.1% and 86.4% (AUC = 0.655, p < 0.05), respectively (“gold” standard CAG). The sensitivity and specificity of the regional MFR to identify the hemodynamic significance of coronary artery stenoses at a value of <1.33 was 100% (the “gold” standard of FFR). Most likely, high sensitivity and specificity in this case are associated with a small number of patients with true stenoses of FFR.Conclusion.The performance of standard MPI in combination with dynamic single-photon emission computed tomography allows to increase the diagnostic significance of the scintigraphic approach in the evaluation of myocardial microcirculation disorders in multivessel coronary artery disease. Dynamic SPECT is a promising method of noninvasive assessment of hemodynamic significance of coronary artery stenoses.