Steinberg G K, De La Paz R, Mitchell R S, Bell T E, Albers G W
Department of Neurosurgery, Stanford Stroke Center, California, USA.
AJNR Am J Neuroradiol. 1996 Feb;17(2):205-12; discussion 213-5.
To evaluate MR imaging and lumbar cerebrospinal fluid enzymes as potential sensitive indicators of cerebral injury after open-heart valve replacement surgery.
Thirty-four patients with cardiac valvular disease were prospectively entered into this study and then underwent valve replacement or repair under cardiopulmonary bypass using a membrane oxygenator. In 26 patients, MR head images were obtained 12 to 24 hours before surgery; repeat MR images were obtained between 1 and 2 weeks after surgery. In 18 patients, lumbar puncture cerebrospinal fluid was analyzed 24 to 48 hours after surgery; the analyses included measurement of lactic dehydrogenase, creatine phosphokinase, adenylate kinase, and neuron-specific enolase.
After surgery, MR imaging showed new ischemic lesions in 15 (58%) of 26 patients: 7 with deep white matter hyperintense lesions; 5 with brain stem, caudate, cerebellar, or thalamic/basal ganglia infarcts; 1 with intraparenchymal hemorrhage; 1 with a subdural hematoma and cortical infarct; and 1 with a corpus callosum lesion consistent with calcium or air. These new ischemic lesions seen on MR images were associated with a focal neurologic deficit in only 4 (27%) of the 15 patients. Neuron-specific enolase and lactic dehydrogenase were abnormally elevated after surgery in 5 (28%) of 18 patients. Adenylate kinase and creatine phosphokinase (brain isozymes) were elevated in one (67%) of the patients. Two (40%) of the five patients with abnormally high neuron-specific enolase or lactic dehydrogenase after surgery also showed a new focal neurologic deficit.
MR imaging is a sensitive measure of subclinical cerebral ischemia after cardiac valve replacement under cardiopulmonary bypass. Cerebrospinal fluid neuron-specific enolase and lactic dehydrogenase are less sensitive than MR imaging for detecting subclinical cerebral ischemia, but these values were elevated after surgery more frequently than was adenylate kinase in our patients.
评估心脏瓣膜置换术后磁共振成像（MR）及腰椎脑脊液酶作为脑损伤潜在敏感指标的价值。
34例心脏瓣膜病患者前瞻性纳入本研究，然后在体外循环下使用膜式氧合器进行瓣膜置换或修复。26例患者在术前12至24小时获取头部MR图像；术后1至2周重复获取MR图像。18例患者在术后24至48小时进行腰椎穿刺脑脊液分析；分析项目包括乳酸脱氢酶、肌酸磷酸激酶、腺苷酸激酶及神经元特异性烯醇化酶的测定。
术后，26例患者中有15例（58%）MR成像显示新的缺血性病变：7例有深部白质高信号病变；5例有脑干、尾状核、小脑或丘脑/基底节梗死；1例有脑实质内出血；1例有硬膜下血肿及皮质梗死；1例有胼胝体病变，符合钙或空气所致。MR图像上这些新的缺血性病变仅在15例患者中的4例（27%）伴有局灶性神经功能缺损。18例患者中有5例（28%）术后神经元特异性烯醇化酶和乳酸脱氢酶异常升高。1例患者（67%）腺苷酸激酶和肌酸磷酸激酶（脑同工酶）升高。术后神经元特异性烯醇化酶或乳酸脱氢酶异常升高的5例患者中有2例（40%）也出现了新的局灶性神经功能缺损。
MR成像是体外循环下心脏瓣膜置换术后亚临床脑缺血的敏感检测方法。脑脊液神经元特异性烯醇化酶和乳酸脱氢酶在检测亚临床脑缺血方面不如MR成像敏感，但在我们的患者中，这些指标术后升高的频率比腺苷酸激酶更高。
