Büyükdereli Gülgün, Kanadasi Mehmet, Kibar Mustafa
Departments of Nuclear Medicine, Cukurova University Faculty of Medicine, Adana, Turkey.
Ann Nucl Med. 2005 Feb;19(1):29-33. doi: 10.1007/BF02986332.
The aim of this study was to evaluate the washout rate of Tc-99m tetrofosmin in asymmetric septal hypertrophy (ASH). As Tc-99m tetrofosmin accumulation and retention depend on sarcolemmal and/or mitochondrial function, the presence or absence of abnormalities in the washout rate of Tc-99m tetrofosmin could provide information about sarcolemmal and/or mitochondrial damage noninvasively. The study group consisted of 18 patients with ASH and 10 healthy subjects. After intravenous injection of 1110 MBq (30 mCi) Tc-99m tetrofosmin, tomographic images were obtained 1 hour later (early image) and again 4 hours later (delayed image). Using tomographic images, the distribution and washout of tetrofosmin in the left ventricle was examined quantitatively. Short-axis SPECT images were divided into 5 segments (anterior, septal, lateral, inferior wall and apex) in early and delayed images, and the mean radioactivity counts were measured in each segment by drawing regions of interest. Washout rates of apex, anterior, septal, lateral and inferior walls were 0.34 +/- 0.06, 0.37 +/- 0.07, 0.36 +/- 0.07, 0.33 -/+ 0.08, 0.33 +/- 0.07 in ASH and 0.20 +/- 0.05, 0.23 +/- 0.05, 0.22 +/- 0.03, 0.21 +/- 0.03, 0.22 +/- 0.03 in the normal group, respectively. In ASH, the washout rates of all myocardial segments were significantly increased as compared to those of the normal controls (p < 0.05). The findings of the present study suggest that there could be dysfunction of sarcolemma and/or mitochondria in the entire left ventricle which would be important in the pathophysiology of this disease. Also our study revealed that Tc-99m tetrofosmin washout was higher in NYHA II-III patients compared to NYHA I patients and the degree of Tc-99m tetrofosmin washout corresponded well with the thickness of the interventricular septum and posterior walls.
本研究的目的是评估锝-99m替曲膦在不对称性室间隔肥厚（ASH）中的洗脱率。由于锝-99m替曲膦的摄取和滞留取决于肌膜和/或线粒体功能，锝-99m替曲膦洗脱率是否异常可无创地提供有关肌膜和/或线粒体损伤的信息。研究组由18例ASH患者和10名健康受试者组成。静脉注射1110 MBq（30 mCi）锝-99m替曲膦后，1小时后（早期图像）及4小时后（延迟图像）获取断层图像。利用断层图像，对左心室内替曲膦的分布和洗脱进行定量检查。短轴SPECT图像在早期和延迟图像中均分为5个节段（前壁、室间隔、侧壁、下壁和心尖），通过绘制感兴趣区测量每个节段的平均放射性计数。ASH组心尖、前壁、室间隔、侧壁和下壁的洗脱率分别为0.34±0.06、0.37±0.07、0.36±0.07、0.33±0.08、0.33±0.07，正常组分别为0.20±0.05、0.23±0.05、0.22±0.03、0.21±0.03、0.22±0.03。ASH患者所有心肌节段的洗脱率均显著高于正常对照组（p<0.05）。本研究结果提示，整个左心室可能存在肌膜和/或线粒体功能障碍，这在该疾病的病理生理学中具有重要意义。此外，我们的研究还显示，与纽约心脏协会（NYHA）I级患者相比，NYHA II-III级患者的锝-99m替曲膦洗脱率更高，且锝-99m替曲膦洗脱程度与室间隔和后壁厚度密切相关。
