Innovative quantitative analysis of left ventricular axis from cardiac SPECT images: XCAT phantom study and clinical validation

Introduction: In this study, we aimed to evaluate the possibility of assessing cardiac abnormality using the left ventricular anatomical axis (LVAA) obtained from short-axis views of myocardial perfusion imaging (MPI).Methods: To obtain LVAA, an ellipse was drawn around the outer wall of SPECT images from XCAT phantoms and patients. The best line was then drawn from the center of all the ellipses in the short-axis views called LVAA. Then, we defined two angles based on LVAA including Ɵ which is the angle created by LVAA with the x-axis, and Φ which is the angle created by LVAA with the z-axis.Results: In this study, ۹۴ cases were enrolled including ۴۸ males (۵۱%) and ۴۶ females (۴۹%) with a mean age of ۶۵.۶۵±۱۰.۰۴. According to the results, there was a significant difference between the two obtained angles and the result of the scan (p<۰.۰۵). The ideal cut-off of Ɵ for an abnormal scan was ۹۱.۷۹ (AUC, ۰.۹۳; p=۰.۰۰۱) with the sensitivity of ۹۸% and specificity of ۸۰%.Conclusion: It can be concluded that LVAA as a quantitative factor is significantly different between normal and abnormal MPS and can be used for the evaluation of MPI.

Keywords:

Myocardial perfusion imaging , SPECT , Cardiovascular imaging , Left ventricular axis , [۹۹mTc]Tc-MIBI