Assessment of the accuracy of IQ SPECT for the quantitative assessment of global left ventricular function in gated myocardial perfusion SPECT: Comparison with cardiac MRI

1755 Objectives IQ SPECT system is a new imaging technology including a multi focal collimator (Smartzoom®), a cardio-centric acquisition orbit and an advanced iterative reconstruction. The aim of this study was to evaluate the accuracy of gated myocardial perfusion single photon emission computed tomography (MPS) with IQ SPECT for the assessment of left ventricular (LV) function. Methods 52 patients with known or suspected coronary artery disease were included retrospectively. All of them performed a MPS using IQ SPECT and a Cardiac MRI (considered as the gold-standard). Left ventricular global function was assessed by measuring LV end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF). MPS data were processed using quantitative gated SPECT software (QGS®). Agreement between IQ SPECT and Cardiac MRI was assessed using Spearman correlation. The optimal threshold in order to diagnose a left ventricular dysfunction was determined using a ROC curve analysis. Results The ventricular volumes obtained with QGS MPS at rest showed good correlations with the cMRI volumes (EDV: r = 0.79; ESV: r = 0.80; p 145mL on CMR) and for the diagnosis of an alteration of the EF ( Conclusions IQ SPECT and QGS showed good correlation with CMR but in order to diagnose an impairment of the left ventricular function, thresholds are significantly lower than CMR for the ventricular volumes and ejection fraction.