Metabolic and ultrastructural abnormalities during ischemia in canine myocardium: noninvasive assessment by positron emission tomography.
Metabolic and ultrastructural abnormalities during ischemia in canine myocardium: noninvasive assessment by positron emission tomography.
复制标题
犬心肌缺血期间的代谢和超微结构异常：正电子发射断层扫描的无创评估。
DOI：
10.1016/s0022-2828(87)80593-x
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发表时间：
1987
影响因子：
5
通讯作者：
Schelbert,HR
中科院分区：
文献类型：
--
作者：
Schwaiger,M;Fishbein,MC;Block,M;Wijns,W;Selin,C;Phelps,ME;Schelbert,HR
正电子发射断层扫描可以对局部心肌血流和代谢进行无创评估。本研究的目的是通过正电子发射断层扫描，将犬缺血心肌的N-13氨摄取作为局部血流量的测量指标，并将C-11棕榈酸动力学作为脂肪酸代谢的标志。此外，代谢结果与在同一动物模型中获得的超微结构结果进行了比较。闭合胸段犬左前降支球囊结扎造成局部缺血。研究的三个心肌部位是缺血段的中心和“边缘”，以及对照心肌。C-11棕榈酸摄取与血流量密切相关(r=0.88)。缺血中心C-11棕榈酸摄取减少，C-11活性清除明显延长。在仅有轻度血流减少和C-11棕榈酸摄取(∼20%)的缺血段的“边缘”，半衰期和剩余活动度与对照组有显著差异。C-11棕榈酸酯初始摄取的标准化残存活性在“边缘”区域最高，这与C-11棕榈酸酯在脂质池中沉积的增加一致。电子显微镜检查显示，11只狗中有8只在相应节段仅有脂滴异常，仅微球血流量轻度减少。因此，这些数据表明代谢成像在细胞水平上表征缺血的潜力。正电子发射断层扫描为检测轻度缺血和确定程度和严重程度提供了一种灵敏的手段。代谢成像可能被证明在临床上不仅有助于识别坏死灶，而且还能识别处于危险状态的心肌。
Positron emission tomography allows the noninvasive assessment of regional myocardial blood flow and metabolism. The purpose of this study was to correlate N-13 ammonia uptake as a measure of regional blood flow and C-11 palmitate kinetics as a marker for fatty acid metabolism in ischemic canine myocardium using positron emission tomography. Furthermore, the metabolic results were compared with ultrastructural findings obtained in the same animal model. Regional ischemia was induced by balloon occlusion of the left anterior descending artery in a closed chest dog model. The three myocardial sites studied were the center and “border” of the ischemic segment as well as the control myocardium. C-11 palmitate uptake closely correlated with blood flow (r=0.88). In the center of ischemia uptake of C-11 palmite was decreased and clearance of C-11 activity significantly prolonged. In the “border” of the ischemic segment with only mild reduction of flow and C-11 palmitate uptake (∼20%) clearance halftime and residual activity were significantly different from control. The residual activity normalized for initial uptake of C-11 palmitate was highest in the “border” regions consistent with increased deposition of C-11 palmitate in lipid pools. The electron microscopic studies showed in 8 of 11 dogs lipid droplets as the only abnormality in corresponding segments with only mild reduction in microsphere blood flow. Thus, these data indicate the potential of metabolic imaging to characterize ischemia on a cellular level. Positron emission tomography provides a sensitive means to detect mild ischemia and to define extent and severity. Metabolic imaging may prove clinically useful to identify not only necrosis, but also myocardium at risk.