Department of Cardiovascular and Respiratory Medicine, Shiga University of Medical Science, Seta, Otsu, 520-2192, Japan,
Ann Nucl Med. 2013 Oct;27(8):737-47. doi: 10.1007/s12149-013-0741-5. Epub 2013 Jun 1.
Decreased heart iodine-123 metaiodobenzylguanidine ((123)I-MIBG) uptake [heart-to-mediastinum count ratio (H/M)] is reported in heart disease (HD) or Lewy body disease (LBD). When LBD is merged, therefore, information regarding HD severity may be ambiguous. We aimed to examine whether lung (123)I-MIBG uptake [lung-to-mediastinum count ratio (L/M)] assessment might be useful for differentiating two clinical conditions of HD and LBD, and to investigate whether L/M could reflect the grade of left ventricular (LV) dysfunction.
Three groups were examined: LBD (patient group with Parkinson's disease or dementia with Lewy bodies, n = 33), PS (group with other Parkinsonian syndromes, n = 20) and HD (group with heart disease). HD consisted of 4 subgroups: HD(I) [H/M(<2.30)-matched group with LBD, n = 34), HD(II) [H/M(≥2.30)-matched group with PS, n = 33], HD(III) [group for functional analysis, LV ejection fraction, first-third and peak filling rates (1/3FR and PFR) and time to PFR were calculated using gated SPECT, n = 35] and HD(IV) (group for examining cardiac prognosis, follow-up period of 1283 ± 506 days, n = 54). Using Doppler echocardiography, a diastolic parameter E/e' and pulmonary artery pressure (ePAP) were estimated.
H/Ms did not differ between HD(I) and LBD, or between PS and HD(II). However, L/Ms were increased in the order of LBD, PS, HD(II) and HD(I) groups. In combined LBD, PS, HD(I) and HD(II), L/Ms correlated positively with a diastolic parameter E/e'. L/Ms correlated with ePAP, while H/Ms did not. H/Ms correlated with a systolic parameter EF (r = 0.56) and diastolic parameters 1/3FR (r = 0.51) and PFR (r = 0.51), and L/Ms correlated with diastolic parameters 1/3FR (r = -0.36) and PFR (r = -0.36) but not with EF in HD(III). Kaplan-Meier analysis showed earlier cardiac death in patients with decreased H/Ms, but not in patients with increased L/Ms in HD(IV).
Our study suggest that increased lung (123)I-MIBG uptake is useful as a reference marker for differentiating two clinical conditions of HD and LBD, and can reflect the degree of LV diastolic dysfunction. Elevated ePAP caused by LV diastolic dysfunction may be involved in the mechanism(s) of increased lung uptake.
据报道，在心脏病（HD）或路易体病（LBD）中，心脏碘-123 间位碘苄胍摄取减少[心脏与纵隔计数比（H/M）]。因此，当 LBD 合并时，有关 HD 严重程度的信息可能会变得模糊。我们旨在研究肺（123）I-MIBG 摄取[肺与纵隔计数比（L/M）]评估是否可用于区分 HD 和 LBD 的两种临床情况，并探讨 L/M 是否可以反映左心室（LV）功能障碍的程度。
检查了三组：LBD（帕金森病或路易体痴呆患者组，n=33）、PS（其他帕金森综合征组，n=20）和 HD（心脏病组）。HD 由 4 个亚组组成：HD（I）[H/M（<2.30）-与 LBD 匹配的组，n=34]、HD（II）[H/M（≥2.30）-与 PS 匹配的组，n=33]、HD（III）[功能分析组，使用门控 SPECT 计算 LV 射血分数、第一至第三和峰值充盈率（1/3FR 和 PFR）和 PFR 时间，n=35]和 HD（IV）（检查心脏预后组，随访时间 1283±506 天，n=54）。使用多普勒超声心动图估计舒张参数 E/e'和肺动脉压（ePAP）。
HD（I）和 LBD 之间或 PS 和 HD（II）之间的 H/M 无差异。然而，L/M 按 LBD、PS、HD（II）和 HD（I）组的顺序增加。在合并的 LBD、PS、HD（I）和 HD（II）中，L/M 与舒张参数 E/e'呈正相关。L/M 与 ePAP 相关，而 H/M 则不相关。H/M 与收缩参数 EF（r=0.56）和舒张参数 1/3FR（r=0.51）和 PFR（r=0.51）相关，而 L/M 与舒张参数 1/3FR（r=-0.36）和 PFR（r=-0.36）相关，但与 HD（III）中的 EF 不相关。Kaplan-Meier 分析显示，HD（IV）中 H/M 降低的患者心脏死亡较早，但 L/M 升高的患者则无。
我们的研究表明，增加的肺（123）I-MIBG 摄取可用作区分 HD 和 LBD 两种临床情况的参考标志物，并可反映 LV 舒张功能障碍的程度。由 LV 舒张功能障碍引起的升高的 ePAP 可能参与了增加肺摄取的机制。
