Department of Nuclear Medicine, Fondazione IRCCS Cà Granda, Milan, Italy.
J Nucl Med. 2010 Dec;51(12):1908-16. doi: 10.2967/jnumed.110.078469. Epub 2010 Nov 15.
Over the last decade, the effects of stem cell therapy on cardiac repair after acute myocardial infarction (AMI) have been investigated with different imaging techniques. We evaluated a new imaging approach using (13)N-ammonia and (18)F-FDG PET for a combined analysis of cardiac perfusion, metabolism, and function in patients treated with intracoronary injection of endothelial progenitors or with conventional therapy for AMI.
A total of 15 patients were randomly assigned to 3 groups based on different treatments (group A: bone marrow-derived stem cells; group B: peripheral blood-derived stem cells; group C: standard therapy alone). The number of scarred and viable segments, along with the infarct size and the extent of the viable area, were determined on a 9-segment (13)N-ammonia/(18)F-FDG PET polar map. Myocardial blood flow (MBF) was calculated for each segment on the ammonia polar map, whereas a global evaluation of left ventricular function was obtained by estimating left ventricular ejection fraction (LVEF) and end-diastolic volume, both derived from electrocardiography-gated (18)F-FDG images. Both intragroup and intergroup comparative analyses of the mean values of each parameter were performed at baseline and 3, 6, and 12 mo after AMI. During follow-up, major cardiac events were also registered.
A significant decrease (P < 0.05) in the number of scarred segments and infarct size was observed in group A, along with an increase in MBF (P < 0.05) and a mild improvement in cardiac function. Lack of infarct size shrinkage in group B was associated with a marked impairment of MBF (P = 0.01) and cardiac dysfunction. Ambiguous changes in infarct size, MBF, and LVEF were found in group C. No differences in number of viable segments or in extent of viable area were found among the groups. At clinical follow-up, no major cardiac events occurred in group A patients, whereas 2 patients of group B experienced in-stent occlusion and one patient of group C received a transplant for heart failure.
Our data suggest that a single nuclear imaging technique accurately analyzes changes in myocardial perfusion and metabolism occurring after stem cell transplantation.
在过去的十年中，不同的成像技术已经研究了干细胞疗法对急性心肌梗死（AMI）后心脏修复的影响。我们使用（13）N-氨和（18）F-FDG PET 评估了一种新的成像方法，用于分析接受冠状动脉内注射内皮祖细胞或常规 AMI 治疗的患者的心脏灌注、代谢和功能。
根据不同的治疗方法，将 15 例患者随机分为 3 组（A 组：骨髓源性干细胞；B 组：外周血源性干细胞；C 组：单独标准治疗）。通过 9 段（13）N-氨/（18）F-FDG PET 极图确定瘢痕和存活段的数量，以及梗死面积和存活区的范围。每个段的心肌血流（MBF）均在氨极图上计算，而通过估计左心室射血分数（LVEF）和舒张末期容积（均来自心电图门控（18）F-FDG 图像）获得左心室功能的整体评估。在 AMI 后 3、6 和 12 个月，对每个参数的平均值进行了组内和组间比较分析。在随访期间，还记录了主要心脏事件。
A 组的瘢痕段数量和梗死面积明显减少（P <0.05），同时 MBF 增加（P <0.05），心脏功能轻度改善。B 组的梗死面积缩小缺乏与 MBF 明显受损（P = 0.01）和心脏功能障碍有关。C 组的梗死面积、MBF 和 LVEF 变化不明确。各组之间的存活段数量或存活区范围没有差异。在临床随访中，A 组患者无重大心脏事件，而 B 组有 2 例患者发生支架内闭塞，C 组有 1 例患者因心力衰竭接受心脏移植。
我们的数据表明，单一核成像技术可准确分析干细胞移植后心肌灌注和代谢变化。
