[Left ventricular function assessed by multigated blood pool single photon emission computed tomography with 99mTc].

To evaluate the usefulness of gated blood pool single photon emission computed tomography with 99mTc (gated SPECT) for assessing left ventricular function, we performed gated SPECT in 2 normal subjects and 18 patients including 13 with ischemic heart disease, 3 with hypertrophic cardiomyopathy and 2 with dilated cardiomyopathy. Left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF) and regional wall motion obtained by gated SPECT were compared with the results of contrast left ventriculography (contrast LVG), echocardiography and planar multigated blood pool imaging (planar blood pool). After the patients' red blood cells were labelled with 30 mCi (1,110 MBq) 99mTc in vivo, gated SPECT was performed in each of 32 projections through a 360 degree arc for each of the cardiac cycle divided into 16. From these images, the left ventricular vertical long-axis image, the horizontal long-axis and short-axis images were reconstructed. To calculate LVEDV, we used serial short-axis images which were composed of the left ventricle. To define left ventricular and left atrial borders, we used amplitude images and cinematic displays of the vertical long-axis image. The level of the optimal cut for delineating the left ventricular border was determined from the volume-cut-level-graph at each background activity, which was constructed by a phantom study. Left ventricular wall motion by gated SPECT was compared with the results of contrast LVG according to segmental analysis. LVEDV obtained by gated SPECT showed an excellent linear correlation with LVEDV calculated by echocardiography (r = 0.98, p < 0.01) and by contrast LVG (r = 0.89, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)