Shimizu Masami, Ino Hidekazu, Yamaguchi Masato, Terai Hidenobu, Hayashi Kenshi, Nakajima Kenichi, Taki Junichi, Mabuchi Hiroshi
Molecular Genetics of Cardiovascular Disorders, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
J Nucl Med. 2002 Jan;43(1):15-20.
Cardiac sympathetic nerve activity is changed in patients with hypertrophic cardiomyopathy (HCM). However, the relationship between heterogeneity of this activity and systolic left ventricular dysfunction in patients with HCM is not well established. This study was performed to evaluate the sympathetic nerve activity in various cardiac regions and to investigate the relationship between cardiac dysfunction and heterogeneity of the cardiac sympathetic nerve activity in patients with HCM.
Cardiac sympathetic nerve activity was evaluated in 25 patients with HCM and 10 control subjects using planar imaging and SPECT by 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy. With planar 123I-MIBG imaging, the heart-to-mediastinum activity ratios (H/M), at early (20 min) and delayed (3 h) acquisition, and the washout rate were calculated. Polar maps of the left ventricular myocardium were divided into 20 segments, and the dispersion (maximal to minimal values) and SD of uptake and the washout rate in 20 segments were calculated.
The early H/M did not differ between the 2 groups. The delayed H/M was significantly lower and the washout rate of the whole heart was significantly higher in the HCM group than those in the control group. In patients with HCM, the delayed H/M, early uptake dispersion, and SD of early uptake showed good correlation with the left ventricular end-diastolic and end-systolic dimensions and the percentage of fractional shortening. A stepwise regression analysis revealed that the SD of early uptake was a powerful determinant for the percentage of fractional shortening in patients with HCM.
These results suggest that the heterogeneity of regional cardiac sympathetic nerve activity may be correlated with cardiac dysfunction in patients with HCM.
肥厚型心肌病（HCM）患者的心脏交感神经活动会发生改变。然而，HCM患者这种活动的异质性与左心室收缩功能障碍之间的关系尚未完全明确。本研究旨在评估不同心脏区域的交感神经活动，并探讨HCM患者心脏功能障碍与心脏交感神经活动异质性之间的关系。
使用平面显像和单光子发射计算机断层扫描（SPECT），通过123I-间碘苄胍（MIBG）心肌显像对25例HCM患者和10例对照者的心脏交感神经活动进行评估。通过平面123I-MIBG显像，计算早期（20分钟）和延迟（3小时）采集时的心脏与纵隔活动比值（H/M）以及洗脱率。将左心室心肌极坐标图分为20个节段，计算20个节段摄取和洗脱率的离散度（最大值与最小值）和标准差。
两组之间早期H/M无差异。HCM组的延迟H/M显著降低，全心洗脱率显著高于对照组。在HCM患者中，延迟H/M、早期摄取离散度和早期摄取标准差与左心室舒张末期和收缩末期内径以及缩短分数百分比具有良好的相关性。逐步回归分析显示，早期摄取标准差是HCM患者缩短分数百分比的有力决定因素。
这些结果表明，HCM患者局部心脏交感神经活动的异质性可能与心脏功能障碍相关。
