Lo Queenie, Hee Leia, Batumalai Vikneswary, Allman Christine, MacDonald Peter, Lonergan Denise, Delaney Geoff P, Thomas Liza
University of New South Wales, Sydney, Australia; Departments of Cardiology and Radiation Oncology, Liverpool Hospital, Sydney, Australia.
University of New South Wales, Sydney, Australia; Departments of Cardiology and Radiation Oncology, Liverpool Hospital, Sydney, Australia; Ingham Institute of Applied Medical Research, Liverpool, Australia.
Int J Radiat Oncol Biol Phys. 2017 Sep 1;99(1):182-190. doi: 10.1016/j.ijrobp.2017.05.030. Epub 2017 May 26.
We examined the utility of echocardiographic 2-dimensional speckle tracking strain imaging (SI) for the evaluation of segmental myocardial dysfunction before and after radiation therapy (RT) and the relationship to dose exposure.
We prospectively recruited 40 women with left-sided breast cancer, undergoing only adjuvant RT to the left chest. Comparisons of traditional echocardiographic parameters and SI parameters at baseline and 6 weeks after RT were analyzed. Regional strain and strain rate (SR) parameters were obtained from all 18 left ventricular segments. The correlation of change in strain parameters with segmental radiation dose was examined.
We observed a significant reduction in global and segmental systolic strain parameters at 6 weeks after RT compared with baseline, with the largest decrement in the apical segments; this corresponded with the segments receiving the highest radiation dose exposure (apical peak systolic strain of -21.21% ± 3.49% before RT vs -18.69% ± 3.34% after RT, percentage change of 11.88%, P=.002; apical peak systolic SR of -1.17 ± 0.24 s before RT vs -1.04 ± 0.19 s after RT, percentage change of 11.11%, P=.008). There was a modest correlation between the apical segment systolic strain reduction and radiation dose exposure (apical segment Δ change and apical radiation dose, r=0.345, P=.031; apical segment percentage change and apical radiation dose, r=0.346, P=.031). A significant reduction in early diastolic SR was observed in the apical segments after treatment compared with baseline (apical early diastolic SR, 1.54 ± 0.45 s before RT vs 1.35 ± 0.33 after RT s; percentage change, 12.34%; P=.034).
Two-dimensional SI detected dose-related regional myocardial dysfunction in the acute phase after RT in chemotherapy-naive left-sided breast cancer patients. Although the long-term effects remain unknown, this imaging modality may have a potential role in the evaluation of irradiation-related cardiotoxicity.
我们研究了超声心动图二维斑点追踪应变成像（SI）在评估放疗（RT）前后节段性心肌功能障碍中的应用及其与剂量暴露的关系。
我们前瞻性招募了40例左侧乳腺癌女性患者，她们仅接受左侧胸部的辅助放疗。分析了基线时和放疗后6周传统超声心动图参数和SI参数的比较。从所有18个左心室节段获取区域应变和应变率（SR）参数。检查应变参数变化与节段性放射剂量的相关性。
与基线相比，我们观察到放疗后6周整体和节段性收缩期应变参数显著降低，心尖节段降低最大；这与接受最高放射剂量暴露的节段相对应（放疗前心尖峰值收缩期应变为-21.21%±3.49%，放疗后为-18.69%±3.34%，变化百分比为11.88%，P = 0.002；放疗前心尖峰值收缩期SR为-1.17±0.24 s，放疗后为-1.04±0.19 s，变化百分比为11.11%，P = 0.008）。心尖节段收缩期应变降低与放射剂量暴露之间存在适度相关性（心尖节段Δ变化与心尖放射剂量，r = 0.345，P = 0.031；心尖节段变化百分比与心尖放射剂量，r = 0.346，P = 0.031）。与基线相比，治疗后心尖节段早期舒张期SR显著降低（放疗前心尖早期舒张期SR为1.54±0.45 s，放疗后为1.35±0.33 s；变化百分比为12.34%；P = 0.034）。
二维SI在未经化疗的左侧乳腺癌患者放疗后的急性期检测到了与剂量相关的节段性心肌功能障碍。尽管长期影响尚不清楚，但这种成像方式可能在评估放疗相关心脏毒性方面具有潜在作用。
