Effect of Attenuation Corrected Myocardial Perfusion SPECT on Left Ventricular Ejection Fraction

Methods: Fifty-one patients were imaged with a simultaneous gated transmission-emission tomographic system. Each patient had biplane contrast ventriculography (CVG) performed within 90 days of the SPECT study. The tomographic data was acquired over 16 frames/cycle, 64x64 matrix, 6.3mm pixels, over 360 degrees for 16 minutes duration. Attenuation corrected (AC) emission images were reconstructed over 360 and 180(RAO-LPO) degree arcs using algorithms previously described. Uncorrected (NC) images were reconstructed (recon) over the same arcs using filtered backprojection. Both AC and NC images were filtered and resliced to provide short axis (SA) data sets. The SA data were input to 3D-MSPECT which computed left ventricular EF and volumes over the cardiac cycle. For comparison, EF values were also computed with the QGS program.