^（99m）Tc－MIBI心肌显像中肺摄取增高及其意义的探讨

Significance of Increased Lung ￣(99m)Tc-MIBI Uptake During Myocardial Imaging

本文从未经处理的心肌断层前位图像上测定了３５例正常人和１３０例心脏病患者的肺／心比值。结果表明，正常人运动心肌显像肺／左室心肌（Ｌ／ＬＶ）比值为０．３５３±０．０４７。以均值＋２Ｓ作为正常值上限时，心肌缺血和高血压病组分别有２４％和２０％的患者Ｌ／ＬＶ增高。心肌梗塞组，静息显像有５１．９％的患者Ｌ／ＬＶ增高。Ｌ／ＬＶ与ＬＶＥＦ之间呈负相关（ｒ＝－０．６１５，ｐ＜０．００１），Ｌ／ＬＶ增高者的ＬＶＥＦ明显低于比值正常者，提示测定肺部^（９９ｍ）Ｔｃ－ＭＩＢＩ的摄取可提供心功能障碍及其程度的资料。

A lung/ heart ratio of ￣(99m)Tc-MIBI uptake was measured from an anterior image of the unprocessed myocardial tomographic image in 35 normal and 130 heart diseases patients. The lung/left ventricle(L/LV) ratios of normal subjects were 0.353±0.047 in exercise images. When the mean +2SD of ratios derived from 35 normal subjects was considered as the normal upper limit, a increased lung-to-heart ratio was found in 24% myocardial ischemia and 20% hypertension patients. However, 14 of 27(51.9%)patients with myocardial infarctions showed an increased ratio at rest. On the other hand, there was a significantly negative(r=-0.6 15,P<0.001) correlation between L/LV ratio and LVEF. LVEF was significantly lower (P<0.01) in subjects with an increased ratio than in those with a normal ratio. Thus the measurement of￣(99m)Tc-MIBI lung / heart ratios may provide information regarding the severity of cardiac dysfunction.