Division of Cardiology, Internal Medicine 3, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3125, Japan.
Department of Diagnostic Radiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3125, Japan.
Eur Radiol. 2021 Jun;31(6):4253-4263. doi: 10.1007/s00330-020-07301-x. Epub 2020 Nov 19.
To study the pulmonary artery (PA) hemodynamics in patients with systemic sclerosis (SSc) using 4D flow MRI (4D-flow).
Twenty-three patients with SSc (M/F: 2/21, 57 ± 15 years, 3 manifest PA hypertension (PAH) by right heart catheterization) and 10 control subjects (M/F: 1/9, 55 ± 17 years) underwent 4D-flow for the in vivo measurement of 3D blood flow velocities in the PA. Data analysis included area-averaged flow quantification at the main PA, 3D wall shear stress (WSS), oscillatory shear index (OSI) calculation along the PA surface, and Reynolds number. The composite outcome of all-cause death and major adverse cardiac events was also investigated.
The maximum PA flow at the systole did not differ, but the minimum flow at the diastole was significantly greater in patients with SSc compared with that in control subjects (7.7 ± 16.0 ml/s vs. ‑ 13.0 ± 17.3 ml/s, p < 0.01). The maximum WSS at the peak systole was significantly lower and OSI was significantly greater in patients with SSc compared with those in control subjects (maximum WSS: 1.04 ± 0.20 Pa vs. 1.33 ± 0.34 Pa, p < 0.01, OSI: 0.139 ± 0.031 vs. 0.101 ± 0.037, p < 0.01). The cumulative event-free rate for the composite event was significantly lower in patients with minimum flow in main PA ≤ 9.22 ml/s (p = 0.012) and in patients with Reynolds number ≤ 2560 (p < 0.001).
4D-flow has the potential to detect changes of PA hemodynamics noninvasively and predict the outcome in patients with SSc at the stage before manifest PAH.
• The WSS at the peak systolic phase was significantly lower (p < 0.05), whereas OSI was greater (p < 0.01) in patients with SSc without manifest PAH than in controls. • The hemodynamic change detected by 4D-flow may help patient management even at the stage before manifest PAH in SSc. • The minimum PA flow and Reynolds number by 4D-flow will serve as a predictive marker for SSc.
使用 4D 流 MRI（4D-flow）研究系统性硬化症（SSc）患者的肺动脉（PA）血流动力学。
23 例 SSc 患者（M/F：2/21，57±15 岁，3 例经右心导管检查表现为 PAH）和 10 例对照者（M/F：1/9，55±17 岁）接受 4D-flow 以活体测量 PA 中的 3D 血流速度。数据分析包括主 PA 的面积平均流量定量、3D 壁面切应力（WSS）、PA 表面沿切应力计算的脉动剪切指数（OSI）以及雷诺数。还研究了全因死亡和主要不良心脏事件的复合结局。
与对照组相比，SSc 患者的收缩期最大 PA 流量无差异，但舒张期最小流量显著增加（7.7±16.0ml/s 比 -13.0±17.3ml/s，p<0.01）。SSc 患者的最大 WSS 在收缩期峰值显著降低，OSI 显著增加（最大 WSS：1.04±0.20Pa 比 1.33±0.34Pa，p<0.01，OSI：0.139±0.031 比 0.101±0.037，p<0.01）。主 PA 中最小流量≤9.22ml/s（p=0.012）和雷诺数≤2560（p<0.001）的患者复合事件的累积无事件率显著降低。
4D-flow 具有无创检测 PA 血流动力学变化并预测 SSc 患者出现 PAH 前阶段结局的潜力。
• SSc 无明显 PAH 患者收缩期峰值 WSS 显著降低（p<0.05），OSI 显著升高（p<0.01）。• 4D-flow 检测到的血流动力学变化有助于 SSc 患者的管理，甚至在出现明显 PAH 之前。• 4D-flow 测量的最小 PA 流量和雷诺数将成为 SSc 的预测标志物。
