Li S, Ikeda J, Takita T, Sekiguchi Y, Demachi J, Chikama H, Goto A, Shirato K
First Department of Internal Medicine, Tohoku University School of Medicine, Miyagi.
J Cardiol. 1998 Nov;32(5):323-9.
The relationship between the myocardial uptake of iodine-123 metaiodobenzylguanidine (123I-MIBG) and heart rate variability parameters has not been determined. This study determined the relationship between the change in myocardial uptake of 123I-MIBG and improvement in left ventricular function after treatment, to determine the usefulness of 123I-MIBG imaging to assess the effect of therapy on heart failure due to dilated cardiomyopathy (DCM). 123I-MIBG imaging and power spectral analysis of heart rate variability were performed before and after treatment in 17 patients with heart failure due to DCM. The following parameters were compared before and after treatment: New York Heart Association (NYHA) functional class, radiographic cardiothoracic ratio (CTR), blood pressure, echocardiographic data [left ventricular end-systolic (LVDs) and end-diastolic (LVDd) diameters, left ventricular ejection fraction (LVEF)], plasma concentrations of norepinephrine and epinephrine, heart rate variability power spectral analysis data [mean low frequency (MLF) and high frequency power (MHF)] and the myocardium to mediastinum activity ratio (MYO/M) obtained in early and late images, and washout rate calculated by anterior planar imaging of 123I-MIBG. The NYHA functional class, LVEF, LVDs, CTR, MLF and MHF improved after treatment. Early MYO/M and late MYO/M improved after treatment. The rate of increase in late MYO/M was positively correlated with the rate of improvement of LVEF after treatment. Furthermore, the late MYO/M was negatively correlated with MLF. Washout rate revealed no correlation with hemodynamic parameters. These findings suggest that late MYO/M is more useful than washout rate to assess the effect of treatment on heart failure due to DCM. Furthermore, the 123I-MIBG imaging and heart rate variability parameters are useful to assess the autonomic tone in DCM with heart failure.
碘-123间碘苄胍（123I-MIBG）心肌摄取与心率变异性参数之间的关系尚未明确。本研究旨在确定123I-MIBG心肌摄取的变化与治疗后左心室功能改善之间的关系，以确定123I-MIBG成像在评估扩张型心肌病（DCM）所致心力衰竭治疗效果方面的实用性。对17例DCM所致心力衰竭患者在治疗前后进行了123I-MIBG成像及心率变异性的功率谱分析。比较治疗前后的以下参数：纽约心脏协会（NYHA）心功能分级、X线心胸比率（CTR）、血压、超声心动图数据[左心室收缩末期（LVDs）和舒张末期（LVDd）内径、左心室射血分数（LVEF）]、去甲肾上腺素和肾上腺素的血浆浓度、心率变异性功率谱分析数据[平均低频（MLF）和高频功率（MHF）]以及早期和晚期图像中获得的心肌与纵隔活性比值（MYO/M），并通过123I-MIBG前位平面显像计算洗脱率。治疗后NYHA心功能分级、LVEF、LVDs、CTR、MLF和MHF均有所改善。治疗后早期MYO/M和晚期MYO/M均有所改善。晚期MYO/M的增加率与治疗后LVEF的改善率呈正相关。此外，晚期MYO/M与MLF呈负相关。洗脱率与血流动力学参数无相关性。这些结果表明，晚期MYO/M在评估DCM所致心力衰竭的治疗效果方面比洗脱率更有用。此外，123I-MIBG成像和心率变异性参数有助于评估伴有心力衰竭的DCM患者的自主神经张力。
