Croteau Etienne, Bénard François, Cadorette Jules, Gauthier Marie-Eve, Aliaga Antonio, Bentourkia M'hamed, Lecomte Roger
Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Sherbrooke, Québec, Canada.
J Nucl Med. 2003 Oct;44(10):1655-61.
18F-FDG PET can identify areas of myocardial viability and necrosis and provide useful information on the effectiveness of experimental techniques designed to improve contractile function and myocardial vascularization in small animals. The left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) in normal and diseased rats were measured in vivo using the high-resolution avalanche photodiode (APD) small-animal PET scanner of the Université de Sherbrooke. The measurements obtained by PET were compared with those obtained by high-resolution echocardiography and with known values obtained from a small, variable-volume cardiac phantom.
List-mode gated (18)F-FDG PET studies were performed using the APD PET scanner on 30 rats: 11 healthy, 4 under septic shock, and 15 with heart failure induced by ligature of the left coronary artery. PET images were resized to match human-scale pixels and analyzed using a standard clinical cardiac software program. The LVV and LVEF from the same animals were also evaluated by echocardiography.
Agreement was excellent between the endocardial volumes determined by PET and the actual volumes of the cardiac phantom (r(2) = 0.96). Agreement between PET and echocardiography for LVV ranged from good in healthy rats (r(2) = 0.89) to fair in diseased rats (r(2) = 0.49). Agreement was fair between LVEF values measured by the 2 methods (r(2) = 0.56). Normal rats had an average LVEF of 83.2% +/- 8.0% using PET and 81.6% +/- 6.0% using echocardiography. In rats with heart failure, LVEF was 54.6% +/- 15.9% using PET and 54.2% +/- 13.3% using echocardiography.
Both PET and echocardiography clearly differentiated normal rats from rats with heart failure. Echocardiography is fast and convenient, whereas list-mode PET is also able to assess defect size, myocardial viability, and metabolism.
18F-FDG PET可识别心肌存活和坏死区域，并为旨在改善小动物收缩功能和心肌血管化的实验技术的有效性提供有用信息。使用舍布鲁克大学的高分辨率雪崩光电二极管（APD）小动物PET扫描仪在体内测量正常和患病大鼠的左心室容积（LVV）和左心室射血分数（LVEF）。将PET获得的测量结果与高分辨率超声心动图获得的测量结果以及从小型可变容积心脏模型获得的已知值进行比较。
使用APD PET扫描仪对30只大鼠进行列表模式门控（18）F-FDG PET研究：11只健康大鼠、4只处于感染性休克状态的大鼠和15只因结扎左冠状动脉而导致心力衰竭的大鼠。将PET图像调整大小以匹配人体尺度像素，并使用标准临床心脏软件程序进行分析。还通过超声心动图评估同一动物的LVV和LVEF。
PET确定的心内膜容积与心脏模型的实际容积之间的一致性非常好（r2 = 0.96）。PET和超声心动图在LVV方面的一致性在健康大鼠中为良好（r2 = 0.89），在患病大鼠中为中等（r2 = 0.49）。两种方法测量的LVEF值之间的一致性为中等（r2 = 0.56）。正常大鼠使用PET的平均LVEF为83.2%±8.0%，使用超声心动图为81.6%±6.0%。在心力衰竭大鼠中，使用PET的LVEF为54.6%±15.9%，使用超声心动图为54.2%±13.3%。
PET和超声心动图均能清楚地区分正常大鼠和心力衰竭大鼠。超声心动图快速便捷，而列表模式PET还能够评估缺损大小、心肌存活和代谢情况。
