1 Cardiology Service, Department of Paediatric Subspecialties, KK Women's and Children's Hospital, Singapore. 2 Department of Pediatrics, University of Toronto, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, Ontario, Canada. 3 Division of Pediatric Cardiology, Stollery Children's Hospital, Edmonton, Alberta, Canada.
Transplantation. 2017 Oct;101(10):2455-2460. doi: 10.1097/TP.0000000000001672.
Unlike adult patients, the utility of cardiopulmonary exercise testing (CPET) in children as a prognostic tool is unclear. We sought to examine the associations of CPET with outcomes in children with dilated cardiomyopathy (DCM).
This was a single-center, retrospective review of children with DCM who underwent CPET. The primary endpoint for this study was a time-dependent composite outcome of hospitalization for management of decompensated heart failure, initiation of mechanical circulatory support, heart transplant, or death.
We examined 52 children with DCM who underwent CPET at median age 12.6 years (interquartile range [IQR], 9.9-14.6 years). At first CPET, the median peak heart rate was 80% (IQR, 70-88%) of predicted, median peak oxygen consumption 62% (IQR, 45-77%) of predicted, and median minute ventilation/carbon dioxide production slope 34.9 (IQR, 27.9-39.4). Eighteen (35%) patients reached the composite outcome during follow-up. Univariable factors associated with the composite outcome included: lower peak heart rate predicted, lower blood pressure response, lower peak oxygen consumption predicted, and higher minute ventilation/carbon dioxide production slope. The association between exercise performance and composite outcome was linear; thus, no reliable cutoff point could be identified. Serial CPET had been performed in 30 patients; clinically, those with deterioration of exercise capacity had poorer outcomes.
Cardiopulmonary exercise testing is feasible in children with DCM and is useful to predict outcomes. The finding of lower exercise capacity and lower blood pressure response should prompt closer follow-up. In those with serial testing, a decline in exercise capacity may be a marker of clinical deterioration.
与成人患者不同，心肺运动测试（CPET）在儿童中的预后价值尚不清楚。我们旨在探讨 CPET 与扩张型心肌病（DCM）患儿结局的相关性。
这是一项对接受 CPET 的 DCM 患儿进行的单中心回顾性研究。本研究的主要终点是因心力衰竭失代偿而住院、开始机械循环支持、心脏移植或死亡的时间依赖性复合结局。
我们检查了 52 名接受 CPET 的 DCM 患儿，中位年龄为 12.6 岁（四分位距 [IQR]，9.9-14.6 岁）。首次 CPET 时，峰值心率中位数为预测值的 80%（IQR，70-88%），峰值氧耗量中位数为预测值的 62%（IQR，45-77%），分钟通气量/二氧化碳产量斜率中位数为 34.9（IQR，27.9-39.4）。18 名（35%）患者在随访期间达到复合结局。单变量分析与复合结局相关的因素包括：峰值心率预测值较低、血压反应较低、峰值氧耗量预测值较低和分钟通气量/二氧化碳产量斜率较高。运动能力与复合结局之间存在线性关系；因此，无法确定可靠的临界点。30 名患者进行了系列 CPET；临床结果显示，运动能力恶化的患者预后较差。
CPET 可用于 DCM 患儿，有助于预测结局。运动能力下降和血压反应降低的发现应提示更密切的随访。对于进行系列检测的患者，运动能力的下降可能是临床恶化的标志物。
