Hara Yuji, Inoue Katsuji, Ogimoto Akiyoshi, Ohtsuka Tomoaki, Shigematsu Yuji, Nakata Shigeru, Higaki Jitsuo
Department of Internal Medicine, Ehime University School of Medicine, Toon City, Japan.
Cardiology. 2005;104(1):16-21. doi: 10.1159/000086048. Epub 2005 May 28.
The beneficial effects of beta-blocker therapy in patients with heart failure have been confirmed. However, the effects of beta-blockers on myocardial perfusion defects are unclear. The aim of this study was to evaluate the effect of beta-blockers on myocardial perfusion defects estimated by thallium-201 myocardial scintigraphy in patients with dilated cardiomyopathy (DCM) and to investigate the relationships between beta-blocker treatment and myocardial damage and cardiac function.
201Tl and echocardiography were performed in 37 patients before and after 6 months of beta-blocker therapy. Extent score (ES) by 201Tl was used to quantitate myocardial perfusion defects before and after treatment.
ES was significantly decreased by beta-blocker therapy. According to the change in ES, DCM patients were classified into three groups, patients who improved, patients showing no change and patients who deteriorated. In the improvement and no-change groups, beta-blocker therapy induced a reduction in left ventricular dimensions and an associated increase in ejection fraction. However, in the deterioration group, left ventricular dimensions and ejection fraction were unchanged. There was a significant relationship between the change in left ventricular dimension at end-diastole and the change in ES.
beta-Blocker therapy could attenuate myocardial perfusion defects in some patients with DCM. The improvement in left ventricular function associated with beta-blocker therapy may be related to the attenuation in myocardial perfusion defects.
β受体阻滞剂治疗对心力衰竭患者的有益作用已得到证实。然而，β受体阻滞剂对心肌灌注缺损的影响尚不清楚。本研究的目的是评估β受体阻滞剂对扩张型心肌病（DCM）患者通过铊-201心肌闪烁显像估计的心肌灌注缺损的影响，并探讨β受体阻滞剂治疗与心肌损伤及心功能之间的关系。
对37例患者在β受体阻滞剂治疗6个月前后进行铊-201心肌显像和超声心动图检查。用铊-201心肌显像的范围评分（ES）对治疗前后的心肌灌注缺损进行定量分析。
β受体阻滞剂治疗后ES显著降低。根据ES的变化，将DCM患者分为三组：改善组、无变化组和恶化组。在改善组和无变化组中，β受体阻滞剂治疗使左心室尺寸减小，射血分数相应增加。然而，在恶化组中，左心室尺寸和射血分数未发生变化。舒张末期左心室尺寸的变化与ES的变化之间存在显著相关性。
β受体阻滞剂治疗可减轻部分DCM患者的心肌灌注缺损。β受体阻滞剂治疗相关的左心室功能改善可能与心肌灌注缺损的减轻有关。
