Incremental value of coronary flow reserve assessed by CZT-SPECT in the diagnosis of coronary ar-tery disease

Abstract

Objective To investigate the incremental value of coronary flow reserve (CFR) assessed by cadmium zinc telluride(CZT)-SPECT as an adjunct to myocardial perfusion imaging (MPI) in the diagnosis of coronary artery disease (CAD). Methods Data of 132 patients (89 males, 43 females; 40-81 years) with or suspected with CAD who successfully underwent rest and stress MPI and CFR from November 2017 to October 2018 in Zhongshan Hospital Affiliated to Fudan University were retrospectively analyzed. Based on coronary angiography (CAG) as the gold standard , the value of MPI and MPI+ CFR in the diagnosis of CAD was evaluated and compared. χ2 test or Fisher exact probability test was used for data analysis. Results Of 132 patients, 61 (46.2%) were CAD with stenosis of at least 75% in one vessel (47.5%, 29/61), two vessels (34.4%, 21/61), or three vessels (18.0%, 11/61). A total of 104 (26.3%) vessels with stenosis of at least 75%, 25 (6.3%) vessels with stenosis of 65%-74%, and 30 (7.6%) vessels with stenosis of 50%-64% were found in 396 vessels. For detecting coronary stenosis of at least 75%, the sensitivity and accuracy of MPI on per-patient analysis were 86.89%(53/61) and 68.94%(91/132), which increased to 96.72%(59/61; χ2=3.921, P<0.05) and 87.88%(116/132; χ2=13.984, P<0.01) by MPI+ CFR. On per-vessel analysis, the sensitivity and accuracy of MPI were 72.12%(75/104) and 77.53%(307/396) and increased to 96.15%(100/104; χ2=22.511, P<0.01) and 85.10%(337/396; χ2=7.479, P<0.05) by MPI+ CFR. The sensitivity of MPI for predicting one, two, and three vessels disease were 72.41%(21/29), 42.86%(9/21), and 5/11 and were improved to 93.10%(27/29; χ2=4.350, P=0.037), 90.48%(19/21; χ2=10.714, P=0.001), and 11/11 (P=0.012) by MPI+ CFR. For coronary with stenosis of 65%-74%, the sensitivity of MPI was 24.00%(6/25) and was improved to 64.00%(16/25; χ2=8.117, P=0.004) by MPI+ CFR. For coronary with stenosis of 50%-64%, the sensitivity of MPI was 40.00%(12/30) and was improved to 76.67%(23/30; χ2=8.297, P=0.004) by MPI+ CFR. Conclusion As an adjunct to MPI, CFR can significantly improve the sensitivity and accuracy in the diagnosis of CAD, particularly for patients with mild stenosis and multivessel CAD. Key words: Coronary artery disease; Fractional flow reserve, myocardial; Myocardial perfusion imaging; Tomography, emission-computed, single-photon; Tellurium; Zinc; Cadmium