Division of Cardiology, Heart Institute, Children's Hospital Colorado, University of Colorado Anschutz Medical Campus , Aurora, Colorado.
Division of Pediatric Cardiac Anesthesiology, Children's Hospital Colorado, University of Colorado Anschutz Medical Campus , Aurora, Colorado.
Am J Physiol Heart Circ Physiol. 2018 Oct 1;315(4):H968-H977. doi: 10.1152/ajpheart.00227.2018. Epub 2018 Jul 13.
The purpose of the present study was to characterize pulmonary vascular stiffness using wave intensity analysis (WIA) in children with pulmonary arterial hypertension (PAH), compare the WIA indexes with catheterization- and MRI-derived hemodynamics, and assess the prognostic ability of WIA-derived biomarkers to predict the functional worsening. WIA was performed in children with PAH ( n = 40) and healthy control subjects ( n = 15) from phase-contrast MRI-derived flow and area waveforms in the main pulmonary artery (MPA). From comprehensive WIA spectra, we collected and compared with healthy control subjects forward compression waves (FCW), backward compression waves (BCW), forward decompression waves (FDW), and wave propagation speed ( c-MPA). There was no difference in the magnitude of FCW between PAH and control groups (88 vs. 108 mm·s·ml, P = 0.239). The magnitude of BCW was increased in patients with PAH (32 vs. 5 mm·s·ml, P < 0.001). There was no difference in magnitude of indexed FDW (32 vs. 28 mm·s·ml, P = 0.856). c-MPA was increased in patients with PAH (3.2 vs. 1.6 m/s, P < 0.001). BCW and FCW correlated with mean pulmonary arterial pressure, right ventricular volumes, and ejection fraction. Elevated indexed BCW [heart rate (HR) = 2.91, confidence interval (CI): 1.18-7.55, P = 0.019], reduced indexed FDW (HR = 0.34, CI: 0.11-0.90, P = 0.030), and increased c-MPA (HR = 3.67, CI: 1.47-10.20, P = 0.004) were strongly associated with functional worsening of disease severity. Our results suggest that noninvasively derived biomarkers of pulmonary vascular resistance and stiffness may be helpful for determining prognosis and monitoring disease progression in children with PAH. NEW & NOTEWORTHY Wave intensity analysis (WIA) studies are lacking in children with pulmonary arterial hypertension (PAH) partially because WIA, which is necessary to assess vascular stiffness, requires an invasive pressure-derived waveform along with simultaneous flow measurements. We analyzed vascular stiffness using WIA in children with PAH who underwent phase-contrast MRI and observed significant differences in WIA indexes between patients with PAH and control subjects. Furthermore, WIA indexes were predictive of functional worsening and were associated with standard catheterization measures.
本研究的目的是使用波强分析（WIA）来描述肺动脉高压（PAH）患儿的肺血管僵硬程度，将 WIA 指标与导管和 MRI 衍生的血液动力学进行比较，并评估 WIA 衍生生物标志物预测功能恶化的预后能力。WIA 是在来自相位对比 MRI 的肺动脉（MPA）主要流动和面积波的 PAH 患儿（n=40）和健康对照组（n=15）中进行的。从综合的 WIA 光谱中，我们收集并与健康对照组比较了前向压缩波（FCW）、后向压缩波（BCW）、前向减压波（FDW）和波传播速度（c-MPA）。PAH 组和对照组的 FCW 幅度没有差异（88 与 108 mm·s·ml，P=0.239）。PAH 患者的 BCW 幅度增加（32 与 5 mm·s·ml，P<0.001）。指数 FDW 的幅度没有差异（32 与 28 mm·s·ml，P=0.856）。PAH 患者的 c-MPA 增加（3.2 与 1.6 m/s，P<0.001）。BCW 和 FCW 与平均肺动脉压、右心室容积和射血分数相关。升高的指数 BCW [心率（HR）=2.91，置信区间（CI）：1.18-7.55，P=0.019]、降低的指数 FDW（HR=0.34，CI：0.11-0.90，P=0.030）和增加的 c-MPA（HR=3.67，CI：1.47-10.20，P=0.004）与疾病严重程度的功能恶化密切相关。我们的结果表明，非侵入性衍生的肺血管阻力和僵硬的生物标志物可能有助于确定 PAH 患儿的预后和监测疾病进展。新观点及重要性 WIA 研究在肺动脉高压（PAH）患儿中缺乏，部分原因是评估血管僵硬所需的 WIA 需要同时进行压力衍生的波形和同步流量测量。我们在接受相位对比 MRI 的 PAH 患儿中使用 WIA 分析血管僵硬，观察到 PAH 患儿与对照组之间的 WIA 指标存在显著差异。此外，WIA 指标可预测功能恶化，并与标准导管插入术测量值相关。
