Feasibility of electrocardiogram-gated coronary artery calcium CT scan for attenuation correction of myocardial perfusion imaging based on a hybrid SPECT/CT scanner

Abstract

Objective \nTo explore the feasibility of electrocardiogram (ECG)-gated coronary artery calcium scoring (CACS) CT scan for attenuation correction of 99Tcm-methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging (MPI) based on a hybrid SPECT/CT scanner. \n \n \nMethods \nFrom January 2017 to October 2017, a total of 110 subjects (61 males, 49 females; age: (68.4±9.4) years) underwent ECG-gated MPI, ECG-gated CACS CT scan and conventional non-gated cardiac CT scan. The gated and non-gated CT scans were used for attenuation correction of MPI separately, then the relative percentage of radioactive distribution of left ventricular (LV) walls (anterior, lateral, inferior, septal and apex) based on different correction methods were compared, and the influences of CACS CT scan and conventional CT scan on visual assessment for myocardial ischemia were also compared. Paired t test and Kappa test were used to analyze the data. \n \n \nResults \nThe relative radioactive distribution percentages of all LV walls in CACS CT corrected MPI and those in conventional CT corrected MPI were not statistically significant (t values: from -0.782 to 0.456, all P>0.05). The weighted Kappa values of LV anterior, lateral, inferior, septal and apex from 2 types of corrected images between 2 physicians were 0.864 (95% CI: 0.749-0.979), 0.795(95% CI: 0.717-0.874), 0.494(95% CI: 0.076-0.912), 0.724(95% CI: 0.321-1.000), 0.873 (95% CI: 0.764-0.982), respectively (all P<0.01). \n \n \nConclusion \nECG-gated CACS CT scan can be used for attenuation correction of 99Tcm-MIBI MPI based on a hybrid SPECT/CT scanner. \n \n \nKey words: \nMyocardial perfusion imaging;\xa0Tomography, emission-computed, single-photon;\xa0Tomography, X-ray computed;\xa0Electrocardiography;\xa0Image processing, computer assisted;\xa0Technetium Tc 99m sestamibi