Yoshinaga K, Tahara M, Torii H, Akimoto M, Kihara K, Tei C
Department of Cardiology, Kagoshima City Medical Association Hospital.
J Cardiol. 2000 May;35(5):343-51.
Myocardial fatty acid metabolism is disturbed in patients with idiopathic dilated cardiomyopathy. Myocardial scintigraphy using iodine-123 15-(p-iodophenyl)-3-R, S-methylpentadecanoic acid(BMIPP) was used to assess the response to beta-blocker therapy in 19 patients with dilated cardiomyopathy. BMIPP myocardial scintigraphy was performed before and 6 months after initiating beta-blocker therapy with metoprolol. Cardiac BMIPP uptake was assessed as the total defect score (TDS) and heart-to-mediastinum activity (H/M) ratio. Patients were classified retrospectively as responders with an improvement of at least one functional class (New York Heart Association) or an increase in ejection fraction of > or = 0.10 at 6 months, or as nonresponders meeting neither criterion. Responders had a significantly better pretreatment TDS (p < 0.005) and H/M ratio (p < 0.0001) than nonresponders. TDS exhibited no significant changes over 6 months in either group (responders: 13.2 +/- 3.7 vs 12.5 +/- 3.3; nonresponders: 20.8 +/- 6.5 vs 20.5 +/- 3.0). Responders showed no significant changes in H/M ratio (2.47 +/- 0.28 vs 2.43 +/- 0.42); paradoxically, nonresponders showed a significant increase from 1.82 +/- 0.11 to 2.10 +/- 0.19 (p < 0.05), suggesting that beta-blocker therapy protected the myocardial fatty acid metabolism even in the absence of clinical improvement. BMIPP myocardial scintigraphy provides a prediction of response to beta-blocker treatment, but does not reflect the therapeutic effect in responders at 6 months.
特发性扩张型心肌病患者存在心肌脂肪酸代谢紊乱。采用碘-123 15-（对碘苯基）-3-R，S-甲基十五烷酸（BMIPP）心肌闪烁显像评估19例扩张型心肌病患者对β受体阻滞剂治疗的反应。在开始使用美托洛尔进行β受体阻滞剂治疗前及治疗6个月后进行BMIPP心肌闪烁显像。通过总缺损评分（TDS）和心/纵隔活性（H/M）比值评估心脏对BMIPP的摄取情况。患者被回顾性分类为反应者（6个月时至少改善一个功能分级（纽约心脏协会）或射血分数增加≥0.10）或未达到上述标准的无反应者。反应者治疗前的TDS（p<0.005）和H/M比值（p<0.0001）显著优于无反应者。两组患者在6个月内TDS均无显著变化（反应者：13.2±3.7 vs 12.5±3.3；无反应者：20.8±6.5 vs 20.5±3.0）。反应者的H/M比值无显著变化（2.47±0.28 vs 2.43±0.42）；矛盾的是，无反应者的H/M比值从1.82±0.11显著增加至2.10±0.19（p<0.05），这表明即使在无临床改善的情况下，β受体阻滞剂治疗也能保护心肌脂肪酸代谢。BMIPP心肌闪烁显像可预测对β受体阻滞剂治疗的反应，但不能反映反应者6个月时的治疗效果。
