Background

Anthracycline anticancer drugs such as epirubicin and doxorubicin may induce myocardial dysfunction, leading to poor prognosis. Early detection of minor left ventricular (LV) myocardial dysfunction is important for the prevention of anthracylcine-induced cardiotoxicity. Using layer-specific speckle tracking echocardiography (STE), we investigated the progressive distribution of myocardial dysfunction in both breast cancer patients and an animal toxicity model.

Methods

Patients with preserved LV ejection fraction (LVEF) preparing for epirubicin chemotherapy (N = 125) were prospectively enrolled. Layer-specific STE, including LV longitudinal and circumferential strains on subepicardium and subendocardium, were evaluated at baseline and after the first cycle, third cycle and six months of epirubicin therapy. A decline of LVEF above 10% to <55% at six months was defined as cardiotoxicity. These same strain measures were obtained in doxorubicin-treated rats and the distribution of myocardial fibrosis evaluated.

Results

In patients developing cardiotoxicity, LV longitudinal strain on subendocardium (LVLSendo) was significantly reduced after three cycles of therapy despite no significant changes in conventional LV systolic, diastolic parameters as well as LV circumferential strains at that moment. Compared to conventional echocardiographic parameters, LVLSendo was significantly predictive of cardiotoxicity. Declines in LVLSendo were also observed in doxorubicin-treated rats at an early stage. These reductions also predicted significant fibrosis in the subendocardial layer.

Conclusion

LVLSendo is useful for the early detection of minor cardiac dysfunction during chemotherapy, thereby implicating endocardial involvement in the development of cardiotoxicity.

中文翻译：

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蒽环类药物引起的心脏毒性对乳腺癌患者心肌变形的特定层分布-从床旁到长凳。

背景

蒽环类抗癌药如表柔比星和阿霉素可能会诱发心肌功能障碍，导致预后不良。早期发现轻微的左心室（LV）心肌功能异常对于预防蒽环霉素诱发的心脏毒性至关重要。使用特定于层的斑点跟踪超声心动图（STE），我们调查了乳腺癌患者和动物毒性模型中心肌功能障碍的逐步分布。

方法

 前瞻性纳入了准备进行表柔比星化疗的左室射血分数（LVEF）保持不变的患者（N = 125）。在基线以及表柔比星治疗的第一个周期，第三个周期和六个月后，评估了特定层的STE，包括在心上皮下和心内膜下的LV纵向和圆周应变。在六个月内，LVEF下降超过10％至<55％被定义为心脏毒性。在阿霉素治疗的大鼠中获得了相同的应变测量值，并评估了心肌纤维化的分布。

结果

在出现心脏毒性的患者中，尽管常规LV收缩压，舒张压参数以及LV圆周应变在那时均没有显着变化，但经过三个疗程的治疗后，心内膜下LV纵向应变（LVLSendo）明显降低。与常规超声心动图参数相比，LVLSendo可以显着预测心脏毒性。在早期用阿霉素治疗的大鼠中也观察到LVLSendo的下降。这些减少也预示着心内膜下层会出现明显的纤维化。

结论

LVLSendo可用于早期发现化疗期间的轻微心脏功能障碍，从而提示心内膜参与心脏毒性的发生。