Correlation of Myocardial p-123I-Iodophenylpentadecanoic Acid Retention with 18F-FDG Accumulation During Experimental Low-Flow Ischemia

Journal of Nuclear Medicine

Edward V.R. DiBella¹  Sami Zoghbi¹  Albert J. Sinusas¹  Robert Soufer¹  Yi-Hwa Liu¹  Frans J.Th. Wackers¹  Lawrence H. Young¹  Cindy Q. Shi¹  Edouard Daher¹  Eliot N. Heller¹ 

关键词: p-¹²³I-iodophenylpentadecanoic acid;    ¹⁸F-FDG;    radionuclide imaging;    myocardium;    ischemia;    fatty acids;    metabolism;    iodinated fatty acid;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

Myocardial ischemia is associated with reduced free fatty acid (FFA) β-oxidation and increased glucose utilization. This study evaluated the potential of dynamic SPECT imaging of a FFA analog, p-123I-iodophenylpentadecanoic acid (IPPA), for detection of ischemia and compares retention of IPPA with 18F-FDG accumulation. Methods: In a canine model of regional low-flow ischemia (n = 9), serial IPPA SPECT images (2 min per image) were acquired over 52–90 min. In a subset of dogs (n = 6), 18F-FDG was injected after completing SPECT imaging and allowed to accumulate for 40 min before killing the animals. Flow was assessed with radiolabeled microspheres. Myocardial metabolism was evaluated independently by selective coronary arterial and venous sampling. Results: Serial IPPA SPECT images showed an initial defect in the ischemic region (0.70% ± 0.03% ischemic-to-nonischemic ratio), which normalized within 48 min because of the slower IPPA clearance from the ischemic region (t1/2 = 54.2 ± 3.3 min) relative to the nonischemic region (t1/2 = 36.7 ± 5.6 min) (P < 0.05). Delayed myocardial IPPA and 18F-FDG activities were correlated (r = 0.70; n = 576 segments), and both were maximally increased in segments with a moderate flow reduction (IPPA, 151% of nonischemic; 18F-FDG, 450% of nonischemic; P < 0.05). Conclusion: Serial SPECT imaging showed delayed myocardial clearance of IPPA in ischemic regions with moderate flow reduction, which lead to increased late myocardial retention of IPPA. Retention of IPPA correlated with 18F-FDG accumulation, supporting the potential of IPPA as a noninvasive marker of ischemic myocardium.

【 授权许可】

Unknown