Wang Y, Takigawa O, Handa S, Hatakeyama K, Suzuki Y
Department of Medicine, Tokai University School of Medicine.
Kaku Igaku. 1996 Sep;33(9):999-1004.
The aims of this study were to clarify the mechanism of giant negative T waves (GNT) in patients with apical hypertrophic cardiomyopathy (AHCM), using myocardial SPECT with thallium-201 (201TI) and iodine-123 metaiodobenzylguanidine (123I-MIBG). Myocardial SPECT in 8 patients with AHCM, diagnosed with GNT in EKG and apical hypertrophy in echocardiogram, were compared with those in 7 normal subjects. The EKG in patients with AHCM showed tall R waves, GNT and ST segment depression in the left precordial leads. With the SPECT, the ratio of radioisotope activities apical ROI vs. other ROI (anterior, septal and lateral segments) were calculated. The ratio of 201TI was high in AHCM, compared with that of normal subjects, suggested the increase in apical myocardial blood flow. The ratio of 123I-MIBG tended to be low in AHCM. The 201TI/123I-MIBG ratio was high in the apical myocardium in AHCM, indicated low sympathetic nerve activities, though there was myocardial hypertrophy. We concluded that giant negative T waves in apical hypertrophic cardiomyopathy might be due to relatively low cardiac sympathetic nerve activities in apical myocardium with idiopathic hypertrophy.
本研究的目的是，通过使用铊 - 201（201TI）和碘 - 123间碘苄胍（123I - MIBG）心肌单光子发射计算机断层扫描（SPECT），阐明心尖肥厚型心肌病（AHCM）患者巨大负T波（GNT）的机制。将8例经心电图诊断为GNT且经超声心动图诊断为心尖肥厚的AHCM患者的心肌SPECT与7例正常受试者的进行比较。AHCM患者的心电图显示左胸前导联R波高大、出现GNT及ST段压低。通过SPECT，计算放射性核素在心尖感兴趣区（ROI）与其他ROI（前壁、间隔和侧壁节段）的活性比值。与正常受试者相比，AHCM患者的201TI比值较高，提示心尖心肌血流增加。AHCM患者的123I - MIBG比值往往较低。AHCM患者心尖心肌的201TI/123I - MIBG比值较高，表明交感神经活性较低，尽管存在心肌肥厚。我们得出结论，心尖肥厚型心肌病中的巨大负T波可能是由于心尖心肌特发性肥厚导致心脏交感神经活性相对较低所致。
