Nagao Michinobu, Baba Shingo, Yonezawa Masato, Yamasaki Yuzo, Kamitani Takeshi, Isoda Takuro, Kawanami Satoshi, Maruoka Yasuhiro, Kitamura Yoshiyuki, Abe Kohtaro, Higo Taiki, Sunagawa Kenji, Honda Hiroshi
Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka City, Fukuoka, 812-8582, Japan,
Int J Cardiovasc Imaging. 2015 Feb;31(2):399-407. doi: 10.1007/s10554-014-0562-1. Epub 2014 Oct 28.
Iron deficiency and cardiac sympathetic impairment play a role in the worsening of heart failure, and these two conditions may be linked. The present study aimed to clarify the relationship between myocardial iron deficiency, cardiac sympathetic activity, and major adverse cardiac events (MACE) in patients with dilated cardiomyopathy (DCM). Cardiac T2* MRI for iron deficiency and (123)I-Metaiodobenzylguanidine (MIBG) imaging for cardiac sympathetic activity were performed in 46 patients with DCM. Myocardial T2* value (M-T2*) was calculated by fitting signal intensity data for mid-left ventricular septum to a decay curve using 3-Tesla scanner. (123)I-MIBG washout rate (MIBG-WR) was calculated using a polar-map technique with tomographic data. We analyze the ability of M-T2* and MIBG-WR to predict MACE. MIBG-WR and M-T2* were significantly greater in DCM patients with MACE than in patients without MACE. Receiver-operating-characteristics curve analysis showed that the optimal MIBG-WR and M-T2* thresholds of 35 % and 28.1 ms, and the two combination predict MACE with C-statics of 0.69, 0.73, and 0.82, respectively. Patients with MIBG-WR <35 % and M-T2* <28.1 ms had significantly lower event-free rates than those with MIBG-WR ≥35 % or M-T2* ≥28.1 ms (log-rank value = 4.35, p < 0.05). Cox hazard regression analysis showed that χ(2) and the hazard ratio were 3.99 and 2.15 for development of MACE in patients with MIBG-WR ≥35 % or M-T2* ≥28.1 ms (p < 0.05). Iron deficiency, expressed by a high M-T2*, and MIBG-WR were both independent predictors of MACE in patients with DCM. The two combination was a more powerful predictor of MACE than either parameter alone.
缺铁和心脏交感神经功能损害在心力衰竭恶化过程中起作用，且这两种情况可能存在关联。本研究旨在阐明扩张型心肌病（DCM）患者中心肌缺铁、心脏交感神经活动与主要不良心脏事件（MACE）之间的关系。对46例DCM患者进行了用于检测缺铁情况的心脏T2磁共振成像（MRI）以及用于检测心脏交感神经活动的（123）I-间碘苄胍（MIBG）显像。使用3特斯拉扫描仪，通过将左心室间隔中部的信号强度数据拟合到衰减曲线来计算心肌T2值（M-T2*）。使用极坐标图技术和断层扫描数据计算（123）I-MIBG洗脱率（MIBG-WR）。我们分析了M-T2和MIBG-WR预测MACE的能力。发生MACE的DCM患者的MIBG-WR和M-T2显著高于未发生MACE的患者。受试者操作特征曲线分析显示，MIBG-WR和M-T2的最佳阈值分别为35%和28.1毫秒，二者联合预测MACE的C统计量分别为0.69、0.73和0.82。MIBG-WR<35%且M-T2<28.1毫秒的患者无事件发生率显著低于MIBG-WR≥35%或M-T2*≥28.1毫秒的患者（对数秩检验值=4.35，p<0.05）。Cox风险回归分析显示，MIBG-WR≥35%或M-T2*≥28.1毫秒的患者发生MACE时的χ2值和风险比分别为3.99和2.15（p<0.05）。高M-T2*所表示的缺铁和MIBG-WR均为DCM患者MACE的独立预测因素。二者联合比单独任何一个参数更能有力地预测MACE。
