Evaluation of left ventricular wall motion and function in patients with previous myocardial infarction by three-dimensional 99mTc-HSAD multigated cardiac pool imaging

To evaluate left ventricular (LV) wall motion stereoscopically from all directions and to calculate the LV volume by 3D imaging, 99mTc-MUGA-SPECT was performed. A new data processing program was developed with the Application Visualization System-Medical Viewer (AVS-MV) based on images obtained from 99mTC-MUGA-SPECT. In patients with previous myocardial infarction, LV function and LV wall motion were evaluated by 3D-99mTc-MUGA imaging. The LV end-diastolic volume (LVEDV) and end-systolic volume (LVESV) were obtained from 3D-99mTc-MUGA images by the surface rendering method, and the left ventricular ejection fraction (LVEF) was calculated at thresholds of 35% (T1), 40% (T2), 45% (T3), and 50% (T4). There was a strong correlation between the LV volume calculated by 3D-99mTc-MUGA imaging at a threshold of 40% and that determined by contrast left ventriculography (LVEDV: 194.7±36.0 ml vs. 198.7±39.1 ml, r=0.791, p<0.001; LVESV: 91.6±44.5 ml vs. 93.3±41.3 ml, r=0.953, p<0.001), respectively. When compared with the LVEF data obtained by left ventriculography, significant correlations were found for 3D images reconstructed at each threshold (T1: r=0.966; T2: r=0.962; T3: r=0.958; and T4: r=0.955). In addition, when LV wall motion obtained by 3D-99mTc-MUGA imaging (LAT and LAO views) was compared with the results obtained by left ventriculography (RAO and LAO views), there was good agreement. (K.H.)