Ruiz Salmerón R J, Jurado López J A, San Martín Gómez M A, Pérez-Castejón M J, Díaz-Buschmann I, Parra Jiménez F J, García de la Villa B, Pérez Blasco P, Pasalodos Pita J, Carreras Delgado J L, Medina Peralta J, García García A, Mateos García M
Instituto de Cardiología de Madrid.
Rev Esp Cardiol. 1998;51 Suppl 1:67-76.
The aim of this study was to differentiate ischemic from nonischemic dilated cardiomyopathy with positron emission tomography. This differentiation is necessary to establish an adequate treatment, and it is often difficult with non-invasive diagnostic procedures.
Ten patients with an echocardiographic diagnosis of dilated cardiomyopathy who had undergone coronary angiography were selected. The presence or absence of angiographic coronary lesions was used to define the ischemic (n = 6) and the nonischemic group (n = 4). The ejection fraction was depressed in both groups, with no significant differences found. A perfusion study with 13N-ammonium and a metabolic imaging with 18F-florodeoxyglucose were performed on each patient. The images were quantitatively and qualitatively analysed, defining three criteria: accumulation defect (areas with activity under 50% of the maximal radioactivity), degree of heterogeneity, and match of images with both tracers. To determinate the degree of heterogeneity, nine segments on the three standard tomographic planes were studied. Based on the following heterogeneity features: irregular borders, coexisting different degrees of accumulation, and patched accumulation, a score ranging from 0 to 3 points was assigned to these segments. To analyse the radioactivity defects and the matching of studies with both tracers, the accumulation defects or the accumulating surface were outlined on a midventricular level coronal plane.
The ischemic group has contrary to the nonischemic one, wider perfusion (0.26 +/- 0.21 vs 0.00) and metabolism defects (0.38 +/- 0.30 vs 0.06 +/- 0.09; p < 0.05). The degree of heterogeneity is significantly higher in the nonischemic group, either in perfusion (14.5 +/- 8.38 vs 2.5 +/- 1.04; p < 0.05) or in metabolism studies (15.5 +/- 3.31 vs 2.33 +/- 1.50; p < 0.005). Assigning wide defects and homogeneous accumulation to ischemic cardiomyopathy, and absence of defects and heterogeneous accumulation to nonischemic cardiomyopathy, the aetiology of the disease was identified in 9 of the 10 cases in the perfusion study and 100% of them with the metabolism imaging.
Positron emission tomography allows to identify the aetiology of dilated cardiomyopathy, either with coronary perfusion or with myocardial glucose metabolism studies. Thus, only one of both PET studies could be used. Ischemic cardiomyopathy is characterised by wide defects and homogeneous radioactivity, and the nonischemic one by the absence of defects and heterogeneous accumulation of the tracer.
本研究旨在通过正电子发射断层扫描区分缺血性与非缺血性扩张型心肌病。这种区分对于确定适当的治疗方法是必要的，而通过非侵入性诊断程序往往很难做到。
选择10例经超声心动图诊断为扩张型心肌病且已接受冠状动脉造影的患者。根据冠状动脉造影病变的有无来定义缺血组（n = 6）和非缺血组（n = 4）。两组的射血分数均降低，未发现显著差异。对每位患者进行了13N-铵灌注研究和18F-氟脱氧葡萄糖代谢成像。对图像进行了定量和定性分析，定义了三个标准：积聚缺损（活性低于最大放射性50%的区域）、异质性程度以及两种示踪剂图像的匹配情况。为确定异质性程度，研究了三个标准断层平面上的九个节段。根据以下异质性特征：边界不规则、并存不同程度的积聚以及斑片状积聚，为这些节段分配0至3分的分数。为分析放射性缺损以及两种示踪剂研究的匹配情况，在心室中部水平冠状面上勾勒出积聚缺损或积聚表面。
与非缺血组相反，缺血组的灌注缺损（0.26±0.21对0.00）和代谢缺损（0.38±0.30对0.06±0.09；p < 0.05）更广泛。非缺血组的异质性程度在灌注（14.5±8.38对2.5±1.04；p < 0.05）和代谢研究（15.5±3.31对2.33±1.50；p < 0.005）中均显著更高。将广泛缺损和均匀积聚归因于缺血性心肌病，无缺损和异质性积聚归因于非缺血性心肌病，在灌注研究中10例患者中有9例确定了疾病病因，在代谢成像中则100%确定了病因。
正电子发射断层扫描可通过冠状动脉灌注或心肌葡萄糖代谢研究来确定扩张型心肌病的病因。因此，两种PET研究使用其一即可。缺血性心肌病的特征是广泛缺损和均匀放射性，非缺血性心肌病的特征是无缺损和示踪剂的异质性积聚。
