RESUMO
We have noted that some patients with ischemic heart disease have a pattern of transient dilation of the left ventricle on the immediate post exercise images as compared with 3 hour redistribution images. We assessed correlation between transient dilation of the left ventricle and coronary arteriographic findings in 32 patients with ischemic heart disease and 15 controls. Initial and delayed conventional short axis tomographic images were obtained after reconstruction of 20 projections acquired over 180 degrees. Thirty six radii by every 10 degrees were generated from the center of the middle myocardial images of the short axis. An area surrounded by thirty six points of maximal count on each radius was calculated in initial and delayed images. Transient Dilation Index (TDI) as an index of dilation was determined by dividing an area in initial image by an area in delayed image. There was no difference in TDI between patients with 1 vessel disease and controls, but TDI in patients with two vessel disease and patients with three vessel disease was larger than that in controls. Thus, transient dilation of the left ventricle on exercise Tl scintigraphy was likely to be related to number of stenotic vessel. We concluded that TDI as a simple quantitative index of transient dilation of the left ventricle was useful for detecting multi vessel stenosis.